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Digital Poster (no CME credit)

Saturday, 11 May Sunday, 12 May Monday, 13 May Tuesday, 14 May Wednesday, 15 May Thursday, 16 May

Saturday, 11 May 2019

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Weekend Course

Diffusion & Microstructure: Fundamentals

Organizers: Dmitry Novikov, Ivana Drobnjak
Room 710B
Saturday 8:00 - 11:30
Moderators: Ivana Drobnjak & Dmitry Novikov
8:00
Fundamentals of Diffusion
Marco Palombo

This lecture introduces key concepts behind the physics of diffusion MRI (dMRI) signal contrast, and motivate why these concepts are relevant in the context of quantifying tissue microstructure. Following this lecture, researchers and clinicians who are interested in understanding the basics of molecular diffusion, will gain intuition about the diffusion process as conceptualised by random-walks of particles, familiarise with representing the diffusion process by the diffusion propagator, understand the regimes in which the diffusion can and cannot be considered Gaussian and understand how these concepts are relevant in the context of tissue microstructure. Hands-on exercises will give intuition into the concepts discussed.

8:45
Diffusion MRI Acquisition, Part I: From Propagator to Image
Jana Hutter

Single-shot Pulsed Gradient Spin Echo echo planar imaging remains the most commonly used sequence for diffusion MRI. However, recent years have seen numerous extensions. This lecture will introduce both the basic modular elements and more experimental novel approaches including modified diffusion preparations, read-out accelerations and combinations with additional contrasts such as relaxometry.

9:30
Break & Meet the Teachers

10:00
Image Artifacts & Processing Pipelines, Part I
Rita Nunes

Diffusion-weighted images (DWI) are corrupted by noise and various imaging artifacts such as Gibbs ringing, EPI and eddy current distortions, motion and other physiological artifacts. The correction of those artifacts is of utmost importance to improve the qualitative, quantitative and statistical inspection of the diffusion data. Here we will give an overview of the major image artifacts, explain how they might confound the DWI analysis, and how they can be corrected for or at least minimized at source or using image processing


10:45
Diffusion MRI Models & Representations
Chantal Tax

The lecture provides researchers and clinicians who use or are planning to use dMRI to quantify the diffusion process and/or tissue microstructure with the basic tools to extract relevant features from the diffusion-weighted signal. The language of the dMRI community regarding signal modelling and representation is introduced. Examples of both signal representations going beyond the Gaussian diffusion regime, and model parameter estimation, are used to give intuition of how these concepts are relevant in the context of tissue microstructure. By solving exercises, the audience will gain intuition into the concepts discussed in the lecture.

11:30
Lunch & Meet the Teachers


Weekend Course

MR Image-Guided Therapy

Organizers: Robert Witte, Kei Yamada
Room 513A-C
Saturday 8:00 - 11:30
Moderators: Robert Witte & Kentaro Akazawa
8:00
MRI for Surgical Planning
Priti Balchandani

This talk discusses the role of MRI in neurosurgical planning and guidance. Specific examples included are the application of ultrahigh field MRI and multi-modal MRI to improved surgical treatment of epilepsy and skull base tumors.

8:25
Self Assessment Module (SAM)

8:30
Temperature Measurement
Kagayaki Kuroda

Noninvasive thermometry is one of the unique features of MRI compared with the other imaging modalities. In this lecture, the basic principles, as well as the latest techniques of MR thermometry such as acquisition acceleration, motion and field change compensation, fat and bone thermometry are explained.

9:00
Laser Therapy in Epilepsy
Robert Watson

Epilepsy cannot be controlled by medications in 30-40% of patients, and in these patients, resection of the epileptogenic focus may be the only hope for a cure.  Traditionally, epilepsy surgeries involve craniotomies with resection of substantial portions of the brain. MR-guided laser interstitial thermal therapy (MRgLITT) provides a minimally invasive alternative. MRgLITT is based on stereotaxic image-guided placement of a small laser fiber into the target and subsequent monitored heating and ablation of the epileptogenic lesion. The technique and advantages, as well as concerns and ways to mitigate them, will be discussed.

9:30
Break & Meet the Teachers

10:00
MR Image-Guided Therapy and Surgery
Jayender Jagadeesan

MR Image-Guided Therapy

10:30
Focused Ultrasound: Basics
David Schlesinger

11:00
MR-Guided Focused Ultrasound Therapy for Brain
Toshio Yamaguchi

This course is designed to provide an introduction of the current status of MRgFUS clinical application in the brain.

11:30
Lunch & Meet the Teachers


Weekend Course

MRI Systems Engineering

Organizers: Greig Scott, Ileana Hancu
Room 516AB
Saturday 8:00 - 17:00
Moderators: Clarissa Cooley & William Handler
8:00
MR Systems Overview
Seung-Kyun Lee

This educational talk is designed to provide a broad overview of the functions and interactions of the subsystems of a modern clinical MRI scanner and explain various design constraints originating from engineering and physiological limitations.

8:30
Magnets: Design, Manufacturing, Installation, Present & Future Technology
Johannes Van Oort

An introduction to the design, manufacturing and installation of MR magnets is presented. Emphasis is placed upon current and future technology of superconducting magnets. Basic coil design is explained, with a brief introduction to the application of superconductivity in MR magnets. Current manufacturing techniques are illustrated with a brief photographic tour. Finally, future industry trends are discussed.

9:00
Magnetic Field Shimming
Robin de Graaf

Magnetic field inhomogeneity affects the performance of almost all MRI and MRS methods, leading to signal loss and image distortion in MRI and loss of spectral resolution in MRS. Spherical harmonics (SH) shimming is the standard tool to improve magnetic field homogeneity, but falls short on complex samples like the human head. The principles and practical aspects of SH shimming are discussed, together with more recent non-SH-based alternatives.

9:30
Break & Meet the Teachers

10:00
Gradient Coil Design Considerations, Manufacturing & Limitations
Blaine Chronik

10:30
Eddy Current Measurement & Compensation
Christoph Barmet

11:00
Peripheral Nerve Stimulation
Rebecca Feldman

Rapidly changing magnetic fields, such as those produced by a switched magnetic field gradient coil can activate nerve fibers in ways that can be perceived as sensation or even induce involuntary muscle contraction or twitching. Gradient induced peripheral nerve stimulation (PNS) will be discussed as well as the limits it imposes on the operation of gradient system.

11:30
Lunch & Meet the Teachers

13:30
MRI Transmitter Amplifier Systems
Michael Twieg

The RF power amplifier (RFPA) is one of several “black box” components in the MRI scanner. The implementation of the RF transmit chain has remained fairly consistent since the earliest clinical MRI scanners, but the advent of parallel transmission (pTX) provides a compelling opportunity to rethink not only the design of the RFPAs and coils, but of the entire MRI scanner. In this lecture we will review fundamental RFPA concepts such as linearity and efficiency. We will then explore advanced topics relating to pTX, including control, decoupling, local amplifiers, and switchmode amplifiers.

14:00
MR Receive Chain
Nicola De Zanche

This lecture covers the components of the RF chain from detection of the signal in the RF coil to its final representation as digital data. Each component is described and its effect on signal strength and quality is discussed.

14:30
RF Field Simulations & Safety Aspects
Simone Winkler

A major challenge that currently hinders the application of Ultra High-Field (UHF) MRI in clinical diagnostics is the non-uniform deposition of radiofrequency (RF) power in the body. Electromagnetic modeling has become a popular tool to assess SAR in simulation [10]-[14]. A diverse family of detailed body models can be used to estimate global SAR and peak local SAR. While SAR values can still vary from patient to patient, with patient position, and with other variables, these simulations provide a strong basis for novel approaches that tackle SAR prediction more accurately [15]-[17]. Given the strong incentive to develop UHF MRI into a clinical tool, it is paramount to find a viable and accurate method for monitoring the spatially varying SAR pattern, and therefore the actual ratio of peak local SAR to global SAR, as the key parameter in MRI safety.

15:00
Break & Meet the Teachers

15:30
MR Linac: Implementations & Challenges
Johan Overweg

Key hardware features and requirements of integrated MR-guided Linac-based radiotherapy systems and practical implementations are explained.

16:00
PET/MR: System Design Considerations
Floris Jansen

This talk is aimed at physicists, engineers, and others who would like a better appreciation of the challenges involved in integrating a PET detector inside a 3T MR scanner. The main challenges involved in integrating a PET detector inside an MR scanner will be explained, and various approaches will be discussed for solving them.

16:30
MR Guided Focused Ultrasound in the Brain: Systems & Applications
William Grissom

Focused ultrasound in the brain has recently been made possible by the advent of MRI monitoring and phased array transducers. The method is currently FDA-approved for ablation of the VIM for essential tremor, and BBB opening and neuromodulation are also being explored. In this talk I will review each of these applications and discuss how they drive the design of MR-guided FUS systems. 

17:00
Adjournment & Meet the Teachers


Weekend Course

Basic MR Spectroscopy

Organizers: Roland Kreis, Malgorzata Marjanska, Wolfgang Bogner
Room 516C-E
Saturday 8:00 - 11:30
Moderators: Erin MacMillan & Atiyah Yahya
8:00
Basic Principles of MRS (Chemical Shift, J-Coupling, Relaxation & Field Strength Effects)
Lars Hanson

The lecture provides a basic understanding of the mechanisms essential to in vivo MR spectroscopy, i.e. those that influence the time and frequency representations of the MR signal in the absence of imaging gradients. Topics include nuclear interactions, the free induction decay (FID), data representations,and signal characteristics in the time and frequency domains. An effort will be made to give intuitive insight and fresh perspectives on the very basics, including interpretations of math frequently appearing in MRS literature.

8:30
Acquisition Methods for Full Profile & Specific Metabolites (STEAM, PRESS, LASER, CSI & MEGA-PRESS)
Assaf Tal

This lecture will cover some of the popular and/or recent MRS localization schemes, including PRESS, STEAM, semi-LASER, LASER, STRESS, MEGA-PRESS and SPECIAL. We will outline the reasons for preferring one module over another. In particular, we will pay special attention to the effect of different modules on coupled resonances - such as those of glutamate, glutamine, GABA, glutathione and lactate - and discuss advantages and disadvantages of each module in detecting each type of metabolite.

9:00
Pre-Acquisition Adjustments (B0 Shimming, B1 Shimming & Water Suppression)
Vincent Boer

In this lecture, the most common pre-scan adjustments for MRS and MRSI will be discussed, as well as the most recent and upcoming developments.

For MRS studies, the pre-scan adjustments are an important factor for achieving best quality and reproducability.

Failing of even one of the adjustments can lead to severe loss in spectral quality.To perform a correct pre-scan adjustment, the user is required to monitor the different preparation steps before starting the actual experiment. Correct preparation of an MRS acquisition requires knowledge of the following steps:

  • B0 field shimming
  • Frequency determination
  • B1 field shimming and flip angle calibration
  • Water suppression

9:30
Break & Meet the Teachers

10:00
Data Processing, Fitting & Quantification
Hélène Ratiney

This lecture tackles the main steps and concepts underlying the quantitative analysis of MR spectroscopic signal in an in vivo context. The goal is to obtain reliable metabolite concentrations from its analysis.

10:30
Matching MR Methods With Appropriate Applications
Robin de Graaf

This presentation will review the decision process to arrive at an optimal combination of MR sequence elements, such as spatial localization, water suppression and spectral editing. Examples of specific applications, metabolites and MR hardware limitations will be provided to demonstrate that an optimal choice for one condition may not necessarily be optimal for a different one. While guidelines and decision trees can help the user under most experimental conditions, an intimate knowledge of each specific MR method is required when straying off the beaten path.

11:00
Spectral Quality (How to Review Your Own & Judge Published Data)
Alexander Lin

11:30
Lunch & Meet the Teachers


Weekend Course

Cutting-Edge Techniques in Body MRI

Organizers: Vikas Gulani, Mustafa Bashir, Utaroh Motosugi
Room 518A-C
Saturday 8:00 - 11:50
Moderators: Susan Noworolski & Kinh Gian Do
8:00
Machine Learning & Deep Learning: Technical Introduction
Florian Knoll

This talk will provide an overview of the technical background of machine learning and deep learning in medical imaging. Common hurdles and pitfalls will be discussed via didactic examples from classification and reconstruction. Examples will be provided from a range of MRI applications, with special focus on body imaging.

8:25
Machine Learning & Deep Learning: Clinical Applications
Shigeru Kiryu

This talk will introduce the clinical applications of deep learning becoming a reality. It will also discuss the unique aspects of deep learning in clinical applications along with its limitations.

8:50
Radiomics: Technical Introduction
Mirabela Rusu

This course is an introduction to Radiomics approaches. The course summarizes the different steps required to pre-process the radiologic images, extract features, reduce the feature sets and the types of analysis that can be performed on these features. Pitfalls of Radiomics analysis are also discussed. 

9:15
Radiomics: Clinical Applications
Masoom Haider

Although quantitative imaging biomarkers are used in clinical care, mining of MRI images to derive quantitative signature based on large feature sets (radiomics) as a distinct approach is primarily a research endeavor in 2019. Approaches to have maximal clinical impact should combine knowledge of MRI physics, biologic sciences, computer vision, medicine and health economics

9:40
Break & Meet the Teachers

10:10
Fast Imaging & Perfusion: Technical Introduction
Yong Chen

Fast imaging techniques are crucial for abdominal MRI. This presentation will first cover the basic concepts of parallel imaging techniques and their usage in accelerating abdominal scans. We will further discuss recent advances in fast imaging techniques and how these techniques enable quantitative perfusion measurement in the abdomen.

10:35
Understanding DCE MRI & Its Potential Clinical Applications
Choon Thng

Basic mathematical concepts and relationships such as convolution, arterial input function, impulse residue function (IRF), microcirculatory parameters such as flow and permeability, tumor concentration time curve are explained qualitatively to facilitate understanding of tracer kinetic modelling and derivation of microcirculatory parameters by curve fitting.  Common DCE MRI parameters such as Ktrans is explained.  More complex models are discussed along with their benefits and trade-offs.  Unique microcirculatory properties of the liver are explained relating to zero fractional interstitial space in normal liver and a positive value for cirrhosis.  Potential clinical applications are briefly discussed.

11:00
Advanced DIffusion Imaging: Technical Introduction
Amita Shukla-Dave

This lecture covers the advancement in the technical development of Diffusion Weighted Imaging (DWI). DWI depends upon the microscopic mobility of water. Water mobility within tissue is highly influenced by the cellular environment, allowing DWI mapping of the diffusion of molecules, mainly water, in biological tissue in vivo and non-invasively. Molecular diffusion in tissues is restricted and reflects interactions with macromolecules, fibers, membranes, etc., revealing details about tissue architecture, which could be either normal or in a diseased state. Thus, DWI has become a non-invasive tool of choice for many clinical applications from assessment of cerebral ischemia to tumor aggressiveness. A series of technical advances, such as developments of echo-planar imaging (EPI), high gradient amplitudes, multi-channel coils, navigator triggered acquisition for motion compensation, and parallel imaging, have been instrumental in extending the application of DWI to the body. However, primary challenges, such as multiple occurrence of motion, persist.

11:25
Clinical applications for advanced body diffusion imaging: challenges and opportunities
Dariya Malyarenko

Notwithstanding technological advances in body DWI acquisition and analysis, their clinical applications remain relatively sparse. Quantitative (q)DWI protocols enable evaluation of sophisticated tissue diffusivity models to derive Gaussian and non-Gaussian parameters (ADC, IVIM, kurtosis) and/or texture-based features (histogram moments and gray-level) of high potential relevance to pathology. Clinically viable qDWI metrics should reflect target pathology using practical acquisition protocol and analysis observing relevant biophysical constraints. By reviewing examples of successful qDWI implementations in clinical oncology studies (for prostate, liver, breast, and whole body metastasis), this lecture will highlight venues to balance existing disparities between research and unmet clinical need.

11:50
Adjournment & Meet the Teachers


Weekend Course

Physics for Physicists

Organizers: Christoph Juchem, Herbert Köstler
Room 520A-F
Saturday 8:00 - 17:00
Moderators: Tobias Wech & Sebastian Theilenberg
8:00
MR Yesterday & Today: An Historic Perspective
Chris Boesch

We are standing on the shoulder of giants! The continuously surprising development of NMR in Chemistry and MR in Medicine is a perfect example how the early work of ingenious individuals enables the current community of researchers to go the next steps forward. This is in particular true if one considers the technical limitations of the early days. While engineers and companies are now providing almost ideal (as compared to the last century) tools with homogeneous high-field magnets, incredible gradient performance, multiple radiofrequency channels, and powerful data handling, many discoveries in the past were technically adventurous.



8:30
Spin Gymnastics: Phase Factor Begets MRI
Yi Wang

The proton spin phase factor of the gradient field is known to found the Fourier encoding system matrix for MR image formation. The phase factors of short-range proton magnetic field, long-range electron magnetic field, and movement in a gradient field also connect MR physics of relaxation, magnetism and transport with tissue biology of cellularity, biomolecularity and vascularity. Therefore, spin phase factors unify explanation of image formation and tissue contrasts.

9:00
The Classical Description & System Overview
Daniel Stäb

While the spin is an intrinsic quantum mechanical property of elementary particles, quantum mechanics are not necessarily required to describe many of the basic processes of NMR or MRI. This lecture aims at providing an intuitive understanding of the NMR phenomenon (including spin precession, RF excitation and relaxation) in conjunction with a brief overview of the basic components of MR systems.


9:30
Break & Meet the Teachers

10:00
MR Toolbox
Martin Krssák

This lecture will introduce and describe most of the “Tools” we are using as building blocks of MR imaging and spectroscopy sequences. It will start with radiofrequency (RF) excitation, use of the phase cycling and building up of spin echo. Principles of slice selection, use of the gradients for signal encoding and spoiling will also be described.  A concept of the extended phase graph (EPG) theory, which is a tool for depicting and understanding the magnetization response of a broad variety of MR sequences will also be introduced.

10:30
The Physics of MR Spectroscopy
Uzay Emir

This presentation aims to provide insight into MR spectroscopy of humans and highlight the essential concepts of chemical shift, spectral dispersion associated with magnetic field strength, shimming, signal suppression, combination schemes for signal processing from phased array coils, sequence approach, and localization sequences.

11:00
Spatial Encoding & k-Space
Gigi Galiana

This course will cover the basic elements of spatial localization, with special focus on how the physics of spin evolution connect to k-space.  This perspective will then be used to describe various phenomena in MRI, including PSFs, Nyquist relations, and non-Fourier encodings.

11:30
Lunch & Meet the Teachers

13:30
MRI Sequences
Jakob Assländer

Bringing together the previously learned building blocks, this course will discuss the basics of MRI pulse sequences with a focus on signal formation and contrast generation. We will shed some light on the overwhelming zoo of sequences (with an even larger number of acronyms) and discuss joint features, as well as the key differences.

14:00
Introduction to RF Pulses
Karl Landheer

The design of proper RF pulses for any magnetic resonance experiment is absolutely critical. Here we discuss basic properties of RF pulses such as the flip angle, duration, and amplitude, and extend into pulse design covering topics such as spatial localization, Shinnar Le-Roux pulses, adiabatic pulses, multi-band pulses and multi-dimensional pulses. Practical design and simulation is emphasized.

14:30
Magnetic Nanoparticles as MR Contrast Agent
Xiaoyuan Chen

Magnetic nanoparticles (MNPs) have been extensively explored as magnetic resonance imaging (MRI) contrast agents. Recent progress in probing MRI relaxivity of MNPs based on structural features at the molecular and atomic scales is reviewed, namely, the structure–relaxivity relationships, including size, shape, crystal structure, surface modification, and assembled structure. A special emphasis is placed on bridging the gaps between classical simplistic models and modern MNPs with elegant structural complexity. In the pursuit of novel MRI contrast agents, it is hoped that this talk will spur the critical thinking for design and engineering of novel MNPs for MRI applications across a broad spectrum of research fields.

15:00
Break & Meet the Teachers

15:30
The Physics of Artifacts
Pedro Ferreira

16:00
Fields in MR & the Physics of Tissue-Field Interactions
Jinfeng Tian

Electromagnetic (EM) fields are one of the fundamental forces in nature, which provide us an insight into the physics of MRI. In the presentation, we will have an overview of the interactions between the EM fields and human body. Audience are expected to understand the basic EM fields and Maxwell equations, the interaction variation with frequency, numerical method election and FDTD procedures to interpret the interactions qualitatively and quantitatively, and a summary of EM simulation applications  in MRI.  

16:30
Numerical Simulation of MR physics
Tony Stöcker

This course provides insight into practical implementation of computer simulations based on classical MR physics. Analytical solutions versus numerical implementations will be discussed. Based on pictorial examples, an introduction to various MRI simulator software packages will be given. Some code snippets will be presented in order to implement MRI physics simulation from scratch

17:00
Adjournment & Meet the Teachers


Weekend Course

Humans Learning to Do Machine Learning Right

Organizers: Demian Wassermann, Matthias Guenther
Room 710A
Saturday 8:00 - 12:00
Moderators: Demian Wassermann
8:00
Best Practices & Pitfalls in Applying Machine Learning to Magnetic Resonance Imaging
Thomas Moreau

8:30
Challenging Conventional Segmentation Evaluation Metrics in Patient MRI
Tal Arbel

9:00
Questions

9:10
Applications for Machine Learning in Medical Imaging
Polina Golland

9:40
Experimental Design for Applications of Machine Learning in Magnetic Resonance in Medicine
Jean Baptiste Poline

This presentation is about the issues that arise from the use of machine learning techniques for the processing of  magnetic resonance images in medicine and in particular brain images. It will discuss the issues of reproducitibility and propose a set of recommendations for setting experimental designs adapted to machine learning applications.

10:10
Break & Meet the Teachers

10:30
State of the Art & Current Problems in Deep Learning
Daniel Rueckert

We will give an overview of the current state-of-the-art in deep learning for medical imaging applications such as reconstruction, segmentation and classification. In particular, we will illustrate deep learning approaches based on Convolutional Neural Networks (CNN). We will focus on deep learning models taht use encoder-decoder networks and show these can be used for tasks such as image reconstruction and image segmentation. We show some applications of CNNs in the context of image classification. Finally, we will discuss some open challenges for deep learning approaches such as explainability and verification of deep learning.

11:00
Questions

11:10
Learning Image Reconstruction: AUTOMAP
Bo Zhu

In this educational talk we describe AUTOMAP, a generalized image reconstruction method utilizing machine learning end-to-end from raw k-space to the final image, enabling reconstruction of arbitrary spatial encoding schemes and encoding spaces (not limited to Fourier) and also featuring noise-robustness which is produced during the training process.

11:30
Machine Learning Applications to Diffusion MRI Microstructure
Marco Palombo

Diffusion MRI (dMRI) signal is sensitive to the tissue architecture at the microscopic scale. Modern machine learning and deep learning techniques can be used to learn the mapping between acquired dMRI signal and specific features of the tissue microstructure. However, experimental design and validation of training sets are essential for reliable supervised and semi-supervised learning and reproducibility and uncertainty of prediction are still open questions. This lecture provides the key concepts behind machine learning applications to dMRI signal analysis for tissue microstructure quantification and show the audience various techniques which have been recently used.  

11:50
Questions

12:00
Lunch & Meet the Teachers


Weekend Course

fMRI: Back to Basics

Organizers: Benedikt Poser, Susan Francis, Richard Buxton, Xin Yu
Room 512A-H
Saturday 8:00 - 11:25
Moderators: Susan Francis & Sriranga Kashyap
8:00
Basic BOLD Physiology
Avery Berman

Functional MRI (fMRI) based on the blood oxygenation level-dependent (BOLD) signal has been used by researchers over the last 25+ years to non-invasively map brain activity and to measure brain physiology. This lecture will explain the basic biophysical principles that enable the use of the BOLD signal as a surrogate measure of brain activity. Topics covered fall into the domains of BOLD-related cerebrovascular physiology (basics of neurovascular coupling) and BOLD MR physics (blood oxygenation-dependence of T2 and T2*). Building on this basic understanding will help us better interpret BOLD signals and their spatial specificity.

8:25
Data Acquisition Basics
Saskia Bollmann

This course gives an introduction to data acquisition for fMRI using echo planar imaging (EPI). Key sequence parameters (voxel size, repetition time, echo time, echo train length, flip angle, parallel imaging, simultaneous multislice) and typical artifacts (ghosting, distortions, signal loss) and their impact on contrast, geometry and speed of EPI time series will be discussed.

8:50
Preprocessing
Cesar Caballero-Gaudes

This talk will describe the main steps of functional MRI data preprocessing based on the blood-oxygenation level dependent (BOLD) contrast. The numerous methods available for each step, and corresponding parameter selection, causes that the amount of possible preprocessing workflows can be enormous, which may lead to substantial variability in the quality of the preprocessed data and final results. We will establish some simple guidelines for adequate preprocessing since there is no ‘optimal’ preprocessing pipeline, but there are incorrectly applied methods, emphasizing that the workflow must be decided according to the characteristics of each dataset and the research question. We will briefly introduce several platforms that can help researchers to design the preprocessing pipeline, automatize its execution, and facilitate data quality assessment. These tools can foster reproducibility, and ensure transparent reporting of methodological details.

9:15
Task-Based fMRI
Alessio Fracasso

Task-based fMRI data is often analysed using the General Linear Model (GLM). This talk introduces this analytical approach starting from its basic concepts, benefits and limitations. Examples will be given showing how it can be used in block and event-related paradigms. Furthermore, the discussion will cover an introduction to the flexible use of the GLM in forward (or encoding) modelling approaches of task-based fMRI as the population receptive field (pRF) analysis.

9:40
Break & Meet the Teachers

10:10
Resting-State fMRI
Ann Choe

In this educational course, basic concepts of the resting state fMRI (rsfMRI) will be outlined, and several widely used data-driven analysis approaches for resting state functional connectivity (rsFC) and their applications will be introduced. The course will also briefly describe the recent emergence of dynamic functional connectivity (dFC) and several of its widely used data analysis approaches.

10:35
High Spatial Resolution fMRI
Jeroen Siero

11:00
High Temporal Resolution fMRI
Laura Lewis

Whole-brain fMRI data can now be acquired at high temporal resolution – on timescales of hundreds of milliseconds. These ‘fast fMRI’ approaches have the potential to reveal new information about brain function. Both acquisition and analysis techniques need to be adapted for fast fMRI in order to exploit its full potential for neuroscience. This lecture will provide an overview of techniques for fast fMRI, how to design fast fMRI studies, and how to model and analyze fast fMRI data. Finally, we will discuss the advantages and limitations of fast fMRI, and highlight potential confounds in interpreting fast fMRI data.

11:25
Lunch & Meet the Teachers


Weekend Course

Diffusion & Microstructure: Frontiers

Organizers: Dmitry Novikov, Ivana Drobnjak
Room 710B
Saturday 13:30 - 17:00
Moderators: Dmitry Novikov & Noam Shemesh
13:30
Microstructure Models, Part I
Valerij Kiselev

We discuss the principles of accessing the tissue microstructure using diffusion MRI. This challenge is decomposed into the forward and inverse problems: the biophysical modeling of the diffusion-weighted MRI signal, and the model parameter estimation, respectively. We focus on the former and briefly discuss the latter. The central phenomenon for the biophysical modeling is the course-graning of the structural details by diffusion. It will be discussed for the regimes of short times (when diffusion reveals the interface surface per unit volume) to long times (when diffusion becomes sensitive to the overall structural organization of tissues). The case of impermeable compartments will be treated separately to clarify the sensitivity of diffusion measurements to the size of small cells

14:15
Diffusion MRI Acquisition, Part II: Adding Dimensions
Filip Szczepankiewicz

This lecture explores how diffusion-weighted experiment can be expanded to include correlations with T1 and T2 relaxation and multidimensional diffusion encoding. The exercises will include calculations relevant to the T2-dependent diffusion encoding, and to the design of non-conventional gradient waveforms.

15:00
Break & Meet the Teachers

15:45
Microstructure Models, Part II
Sune Jespersen

We discuss tissue microstructure from the point of view of biophysical modeling, using the so-called Standard Model of diffusion in the brain as our primary example. We review its assumptions, potential regimes of validity, validation studies, and approaches for parameter estimation. Prominent among these are “orthogonal measurements”, where e.g. diffusion pulse sequences employing generalized q-space trajectories may play an important role.

16:30
Image Artifacts & Processing Pipelines, Part II
Jelle Veraart

In the second part of this topic, we focus on more advanced image processing methods. We will give an overview of image denoising methods, Gibbs ringing removal, outlier detection, frequency stabilization, effects of gradient nonlinearity, and discuss challenges of pushing for higher spatial resolution.


17:15
Adjournment & Meet the Teachers


Weekend Course

Hyperpolarized MR Spectroscopic Imaging

Organizers: Yi-Fen Yen, Catherine Hines, Damian Tyler, Malgorzata Marjanska
Room 513A-C
Saturday 13:30 - 16:40
Moderators: Matthew Rosen
13:30
Get the Hype: The Physical Bases of Dynamic Nuclear Polarization for Medical Uses
Lucio Frydman

This talk will discuss the physical basis of the DNP NMR/MRI experiment.  Attention will focus on alternatives to do the hyperpolarization component in either solutions or in the solid state, focusing in particular on the Overhauser, on the Solid and on the Cross Effects for the sake of maximizing the nuclear polarization.  The parameters that each of these methods requires to work best –including their respective advantages and drawbacks– will be explained. On the basis of this, the procedures that may then enable their respective utilization in bioimaging settings will be introduced

13:50
Physics & Chemistry of d-DNP for Biomedical Imaging
Mikko Kettunen

Dissolution dynamic nuclear polarisation (d-DNP) method allows hyperpolarisation of a broad range of molecules, yielding >10,000-fold increase in 13C signal-to-noise ratio. Hyperpolarisation is achieved through microwave-induced polarisation transfer from electrons to nuclei at solid-state followed by rapid dissolution. d-DNP places some limitations to suitable marker molecules, however. In this talk, the basics of d-DNP and chemistry involved will be discussed.  

14:10
MR/MRSI Acquisition Strategies
Angus Lau

Dynamic nuclear polarization and dissolution offer the exciting possibility of imaging biochemical reactions in vivo, including some of the key enzymatic reactions involved in cellular metabolism. For MR metabolic imaging using 13C‐labeled compounds and DNP, the desired information lies in both the spectral domain, with the relative amplitudes of the different chemical shift species, as well as in the spatial domain. This necessitates some form of spectral encoding together with the acquisition of imaging data, which strongly influences the design of pulse sequences for this application. We will discuss how to efficiently use the limited available hyperpolarized magnetization in conjunction with available imaging pulse sequences.

14:30
Applications of d-DNP in Pre-Clinical Research
Kerstin Timm

Dissolution dynamic nuclear polarization (d-DNP) has made possible the in vivo measurements of biochemical reactions using MR spectroscopy and different imaging strategies. This presentation will focus on the available pre-clinical models used for d-DNP as well as a range of hyperpolarized 13C-labelled substrates that have been employed thus far. The talk will furthermore outline the necessary steps that have to be taken when planning pre-clinical d-DNP studies, ranging from the choice of model system over practical considerations to the actual hyperpolarized probes and their chemical modifications. The presentation will conclude by pointing towards potential future applications and optimizations of d-DNP.

14:50
Break & Meet the Teachers

15:20
PHIP & SABRE Techniques
Thomas Theis

Parahydrogen Induced Polarization (PHIP) is a relatively new hyperpolarization technique, first described in 1986. PHIP has advanced to enable important applications including biomolecular imaging with hyperpolarized MRI markers. Compared to other hyperpolarization techniques, PHIP is particularly simple and easy to implement but also faces critical challenges that still need to be addressed for widespread use. In this tutorial, insight into fundamental PHIP spin physics is given and it will be illustrated how such fundamental insight can drive innovation towards broader adaption of the technology in medical applications.

15:40
Imaging Applications of PHIP & SABRE
Meghan Halse

In this presentation, the latest developments towards imaging applications of parahydrogen-based hyperpolarisation methods will be discussed. Recent advances of both the hydrogenative parahydrogen-induced polarisation (PHIP) and non-hydrogenative signal amplification by reversible exchange (SABRE) methods will be explored. In particular the talk will focus on developments in key aspects of clinical relevance including the optimisation of hyperpolarisation levels and lifetimes, strategies for increasing the range of agents amenable to hyperpolarisation, and developments that will allow for the delivery of biocompatible agents including both the solvent conditions and the removal of the transition metal catalyst.

16:00
SEOP & MEOP
Boyd Goodson

Once limited to the realm of fundamental physics experiments, hyperpolarized (HP) noble gases have been exploited to enhance magnetic resonance signals for a wide range of applications, including biomedical and clinical imaging. The purpose of this tutorial is to introduce the principles and practice of the primary methods of preparing hyperpolarized noble gases: spin-exchange optical pumping (SEOP) and metastability-exchange optical pumping (MEOP). Alternative approaches (e.g. dynamic nuclear polarization, DNP), will also be discussed. 

16:20
Hyperpolarized Gas Imaging - A Focus on Ventilation
Jason Woods

Hyperpolarized-gas MRI has seen a steadily increasing, albeit tortuous, path toward relevance in pulmonary medicine.  During the last 10 years, the field has seen an increased focus on 129Xe, which can be used to measure regional ventilation, to characterize the size of alveolar spaces (diffusion MRI), and to measure gas exchange between the airspaces, red blood cells, and interstitium/plasma. This presentation will focus on ventilation imaging and the relevance of ventilation imaging to sensitive detection of early, regional lung obstruction.  Application to well-characterized patient populations has allowed detailed comparisons of hyperpolarized-gas MRI to clinically-accepted techniques, demonstrating high sensitivity. 

16:40
Adjournment & Meet the Teachers


Weekend Course

Myelin

Organizers: Cornelia Laule, Alex MacKay
Room 516C-E
Saturday 13:30 - 17:00
Moderators: Cornelia Laule & Alex MacKay
13:30
What Is Myelin & Why Is It Important to Image?
Samuel Ludwin

13:50
Magnetization Transfer Techniques
Guillaume Duhamel

The potential of Magnetization Transfer techniques (MTR, qMT and ihMT) for myelin imaging is presented

14:10
Myelin Water Imaging
Shannon Kolind

Myelin water imaging (MWI) provides quantitative measurements specific to myelin by separating the MRI signal into contributions from the various water pools present within a voxel. In central nervous system tissue these water pools generally correspond to intra- and extra-cellular water, which relaxes slowly, and water trapped between the myelin bilayers, which relaxes quickly. The fraction of water corresponding to the water trapped within the myelin sheath, the myelin water fraction (MWF), provides a quantitative measure related to myelin content. This course will discuss acquisition and analysis techniques as well as common artefacts and pitfalls.

14:30
T1 & T1w/T2w
Christine Tardif

This talk describes two methods used for imaging myelin content in vivo: T1 mapping and T1-weighted/T2-weighted (T1w/T2w) signal ratio imaging. Their advantages and limitations will be discussed in comparison to other techniques presented in the Myelin Imaging session.

14:50
Break & Meet the Teachers

15:20
Ultra Short TE
Mark Does

Magnetic resonance imaging (MRI) contrast can be highly sensitive to the presence of myelin; however, quantitative MRI approaches to measure myelin content remain a challenge. With ultra-short echo time (UTE) MRI, it may be possible to directly image the rapidly-relaxing non-aqueous protons in the phospholipid bilayers that comprise myelin. UTE-MRI brings with it technical challenges, and the MRI characteristics of the ultra-short T2 signal from myelin is not yet well understood. Several studies have presented UTE-MRI of brain thought to reflect myelin, but questions remain and further work is needed to validate this approach.

15:40
Synthetic Myelin Imaging
Marcel Warntjes

Synthetic MR imaging is a method that creates conventional  T1W, T2W and FLAIR images by measuring the T1 and T2 relaxation times. The method can only resolve slow relaxation components, but by using a model for myelin including magnetization exchange, it can infer the presence of myelin. The advantage of the method is the short scan time, where typically full head coverage is obtained in 6 minutes. A new sequence is developed where even a 1 mm isotropic resolution can be obtained in that scan time. An overview is provided of the measurements, modeling and clinical application of myelin detection using synthetic MRI.

16:00
T2*
Dong-Hyun Kim

Recently, there has been numerous research on myelin water imaging via T2* contrast, e.g. based on multi gradient-echo imaging. In this talk, I will present the methodology of T2* based myelin water imaging. Acquisition and reconstruction methods will be presented. Also, the pros and cons of T2* based myelin water imaging and challenges will be discussed.  

16:20
Exploring myelin content changes with Positron Emission Tomography: application to multiple sclerosis
Benedetta Bodini

Measuring myelin content changes in living patients is essential to understand the mechanisms underlying demyelinating diseases such as multiple sclerosis (MS). Several advanced MRI techniques have proven to be extremely sensitive for detecting microstructural changes affecting brain tissues of patients with MS. However, since similar changes in the physical properties of tissues detected by MRI can result from multiple pathological processes indistinguishable from each other, the interpretation of imaging data acquired with MRI remains challenged by an intrinsic suboptimal specificity. Being based on the use of radiolabeled compounds selectively binding to specific biological targets, positron emission tomography (PET) offers the highest possible specificity to explore myelin content changes in the human brain.

16:40
Panel Discussion

17:00
Adjournment & Meet the Teachers


Weekend Course

Hepatobiliary

Organizers: Utaroh Motosugi, Mustafa Shadi Bashir, Claude Sirlin
Room 518A-C
Saturday 13:30 - 15:10
Moderators: Johannes Heverhagen & Utaroh Motosugi
13:30
Benign Primary Liver Tumors
Hero Hussain

Focal liver lesions are frequently encountered and represent a wide spectrum of pathologies. While most these lesions are benign, especially in the absence of history of malignancy and chronic liver disease, many will undergo MR imaging for characterization and reassurance. The radiologist must therefore be aware of typical and atypical imaging features of benign lesions on MR imaging, to avoid unnecessary extra tests and procedures.

13:55
Malignant Primary Liver Tumors
Takamichi Murakami

Malignant primary liver tumors are classified according to their origins in the 4th WHO classification. They mostly consist of epithelial tumors such as hepatocellular carcinoma and intrahepatic cholangiocarcinoma, which are the first and second most common liver malignancies. Although each malignancy has unique imaging features on CT and MRI that lead to differential diagnosis, they are sometimes difficult to distinguish due to similarities in the backgrounds or due to combined tumors which have features of both malignancies. In this lecture, typical and atypical imaging features of those liver malignancies with reference to the current topics and considerations will be presented.

14:20
Biliary Disease
Mi-Suk Park

Biliary disease: A pattern-based approach and differential diagnosis 

14:45
Diffuse Liver Disease
Takeshi Yokoo

Recent advances in MRI for liver fat, iron, and fibrosis quantification has enabled “virtual liver biopsy” for patients with diffuse liver disease, and these technologies are now widely available for clinical care. The purpose of this educational session is to inform physicians and physicists of these new MRI capabilities and their potential value in clinical practice.

15:10
Break & Meet the Teachers


Weekend Course

Statistical Analysis for Imaging Studies

Organizers: Dwight Nishimura
Room 710A
Saturday 13:30 - 17:00
Moderators: Dwight Nishimura & Sharon Clarke
13:30
Foundations of Imaging Study Design
Chaya Moskowitz

This half-day Educational Course will provide an introduction to statistical methods for imaging studies. The course will focus on concepts of study design and data analysis that are frequently used in imaging studies. Topics to be covered include prospective and retrospective studies, error rates and hypothesis testing, ROC curves, basic sample size calculations, methods for evaluating quantitative imaging biomarkers, and statistical concepts in radiomics analysis.

14:00
Statistical Estimation & Hypothesis Testing
Mithat Gonen

14:30
Break & Meet the Teachers

14:45
Statistical Methods for Evaluating the Accuracy of Imaging Tests
Chaya Moskowitz

15:10
Power & Sample Size Calculation for Imaging Studies
Mithat Gonen

15:35
Break & Meet the Teachers

15:50
Concepts in Quantitative Imaging Biomarker Evaluation
Chaya Moskowitz

16:15
Radiomics from a Statistician’s Perspective
Mithat Gonen

16:40
Questions

17:00
Adjournment & Meet the Teachers


Weekend Course

Physiology & Hemodynamics

Organizers: Hanzhang Lu, Richard Buxton, Susan Francis, Benedikt Poser
Room 512A-H
Saturday 13:30 - 16:40
Moderators: Richard Buxton & Benedikt Poser
13:30
Neurovascular Coupling
Claudine Gauthier

The brain has a high energy demand, but cannot store energy. Consequently, it requires an uninterrupted and tightly controlled influx of blood to function. Neurovascular coupling comprises all mechanisms that determine cerebral blood flow (CBF) regulation following neuronal activity. The neurovascular unit is highly complex, involving excitatory neurons, interneurons, components of blood vessel walls such as smooth muscle cells and pericytes, as well as perivascular cells such as astrocytes and macrophages. All these cells can release molecules that can lead to vasodilation or vasoconstriction, and thereby determine the CBF response that accompanies neuronal activity, and therefore hemodynamic imaging signals.

13:50
HRF: Modeling & Transients
Martin Havlicek

Hemodynamic response measured with blood oxygenation level-dependent (BOLD) fMRI typically exhibit transients in the form of early-overshoot and post-stimulus undershoot. These transients originate from dynamic relationships between different physiological variables. They can be related to (1) active neuronal and metabolic processes reflecting changes in excitatory-inhibitory (E-I) balance; or (2) passive vascular venous blood volume changes due to vessel viscoelasticity. In this lecture, I will explain how dynamic physiological models, accounting for both active and passive mechanisms underlying BOLD response (BR) transients, can help us to study dynamic changes in E-I balance using fMRI data.

14:10
Laminar Physiology
Laurentius Huber

Recent methodological advancements of fMRI allow researchers to approach the mesoscopic regime of cortical layers and columns. This revolutionizes the ability to tackle cortical information processing within brain systems. In order to interpret the layer-dependent fMRI signal, however, the underlying laminar physiology must be understood. In this educational lecture, I will give an overview of the physiology of blood vessels within GM and discuss how this physiology affects the interpretation of layer-fMRI signal changes. I will give an overview of the corresponding fMRI analysis challenges. And finally, I will discuss how intra-cortical blood vessels can differently affect fMRI contrasts of BOLD and non-BOLD sequences.  

14:30
Cardiovascular Response
Kevin King

We will discuss how new MRI techniques allow us to identify various stages of brain response to cardiovascular disease.  


14:50
Break & Meet the Teachers

15:20
Calibrated BOLD
Daniel Bulte

Blood oxygenation level dependent (BOLD) functional MRI is a powerful tool for localising neural activity, but it provides an ambiguous physiological signal. A number of methods exist for calibrating the BOLD signal in order to provide either relative changes in a physiological parameter such as CBF and CMRO2 during the performance of a task, or to produce quantitative maps of physiological parameters at rest. This session will introduce the basic science behind some of the most popular methods of BOLD calibration.

15:40
MRI Measurement of OEF and CMRO2
Felix Wehrli

The cerebral metabolic rate of oxygen (CMRO2) is fundamental to tissue metabolism. Determination of CMRO2 demands knowledge of the arterio-venous difference in hemoglobin-bound oxygen concentration, typically expressed as oxygen extraction fraction (OEF), and cerebral blood flow rate (CBF).  MRI is uniquely suited for measurement of both these quantities, yielding CMRO2 in absolute physiologic units of µmol O2 min-1/100g tissue. Two approaches will be discussed, both relying on hemoglobin magnetism. The first is based on measurement of blood water T2, which is modulated by diffusion and exchange in the local induced fields in the vicinity of erythrocytes. The second exploits the blood’s bulk magnetic susceptibility, which can be derived from field maps.

16:00
Understanding Baseline: Arterial Compliance
Esther Warnert

Understanding Baseline: Arterial Compliance.

16:20
Understanding Baseline: Non-Gd BBB
Jack Wells

Alterations to the integrity of the blood brain barrier (BBB) appear to be mechanistically important in the development of neurodegenerative disease. Traditionally, BBB integrity is measured by investigating the transfer of intravascular contrast agents, such as gadolinium or evans blue, into the brain parenchyma. Alternative, non-invasive, MRI techniques have been proposed that harness arterial spin labelling sequences to assess the permeability of the BBB to water, potentially yielding a sensitive marker of subtle pathological changes. In this lecture I will review these non-invasive techniques and how they have been applied to investigate abnormalities to BBB integrity in disease.      

16:40
Adjournment & Meet the Teachers


Weekend Course

Imaging of Prostate Cancer

Organizers: Daniel Margolis, Utaroh Motosugi
Room 518A-C
Saturday 15:40 - 16:55
Moderators: Masoom Haider & Daniel Margolis
15:40
Imaging for Biopsy Planning
Leonardo Bittencourt

In this presentation, we will discuss about imaging and clinical variables that may help achieve a better performance on MR-TRUS fusion-guided biopsies of the prostate.

16:05
Imaging for Surgery, Focal Therapy & Radiation Treatment Planning
Satoru Takahashi

Basis, characteristics and indication of potential definitive therapy for the prostate cancer; including radical prostatectomy, radiotherapy, local ablation therapy, will be demonstrated for better understanding of the appropriate management of newly diagnosed prostate cancer.

Surgical and radiological anatomy of crucial structures for preventing complications of radical prostatectomy, as well as tips, trick and pitfalls for visualizing and evaluating vital structures will be discussed.


16:30
Imaging in the Post-Treatment Setting
Sadhna Verma

Learning Objectives

Describe prostate cancer treatment options (active surveillance, surgery, radiation, and focal therapies) and their imaging findings.

Recognize the importance of new MRI and PET techniques in the detection of recurrence after hormone, radiation, prostatectomy and focal therapies.

Understand the importance of MR imaging in surveillance after focal therapy and its role in triage and follow-up of patients who undergo active surveillance.


16:55
Adjournment & Meet the Teachers



Sunday, 12 May 2019

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Weekend Course

Basics of Molecular Dynamic Sensitive MRI; MT, CEST & Rotating-Frame Relaxation

Organizers: Kannie WY Chan, Gregory Metzger
Room 512A-H
Sunday 8:00 - 12:00
Moderators: Greg Stanisz & Jiadi Xu
8:00
Quantitative Magnetization Transfer Imaging for Characterizing Pathology
Seth Smith

The purpose of this presentation is to provide an overview of the basics of quantitative magnetization transfer (qMT) MRI acquisition, analysis, and implementation.  We will additionally provide an overview of the application of qMT in health and disease and examine the opportunities for qMT in characterizing pathology.

8:35
CEST MRI for Beginners
Eleni Demetriou

What is the origin of CEST contrast in tissues? What are the basic steps for generating CEST contrast maps including acquisition and post-processing of CEST MRI data? What are its current applications and its limits? The purpose of this talk will be to outline the basic mechanisms of CEST either through MRS or imaging. To discuss the progress of CEST imaging towards clinical practise and to highlight extraordinary developments within this field.

9:10
Bringing It All Together: Relaxation, T1rho, T2rho & CEST
Elena Vinogradov

Spin-lock  experiments employ RF to probe dynamic processes in molecules. CEST also employ RF to create contrast and explore spin dynamics. In all these cases, in the presence of RF, an effective field is formed and the relaxation processes are governed by the constants parallel and perpendicular to the effective field – T1rho and T2rho­.  We will dwell in more details on the basic principles, equations and features governing relaxation and dynamics processes in these methods.

9:45
Break & Meet the Teachers

10:15
Exploiting Relaxation Along Fictitious Fields
Silvia Mangia

The SNR increase of high fields needs to be leveraged with the challenge of maintaining the flexibility of tuning the MRI contrast to the molecular dynamics of interest. Relaxation methods based on frequency-modulated pulses, including T and T using adiabatic pulses, and the non-adiabatic method entitled relaxation along a fictitious field (RAFF) in the rotating frame of rank 'n' (RAFFn), offer sensitivity to molecular dynamics in intermediate and slow regimes. The reduced power deposition of RAFFn, along with the opportunity of enhancing sensitivity to exchange by tuning the periodicity of irradiation, are distinct and compelling advantages of the methodology.

10:50
C’est La Vie: Selected Topics on In Vivo CEST
Lucio Frydman

This talk will center on analyzing the potential associated with CEST-based MRI, based on both the method’s physical principles and on experiences with in vivo rodent experiments.  Following an initial description on how molecular-based information can be extracted based on chemical exchanges of labile molecular protons with the solvent, attention will be focused on methods to improve the resolution and specificity of the method. Various acquisition modes, pulse sequences and acquisition conditions, will be introduced. On the basis of these procedures, applications geared at observing dynamic processes related to tumor progression, to biochemical metabolism and to functional stimuli, will be discussed.

11:25
Role of Molecular Dynamic Imaging in Musculoskeletal Applications
Mikko Nissi

This course part covers the applications of molecular dynamic imaging, or more precisely, MT/CEST, T2, T1rho, adiabatic T1rho and T2rho, and RAFF relaxation times in the musculoskeletal applications. The lectures will briefly cover possible musculoskeletal targets for the methods, focusing mostly on articular cartilage which is most frequently studied and affected in musculoskeletal disorders. Furthermore, the methods will be briefly overviewed with respect to the musculoskeletal application, followed by their potential uses.

12:00
Lunch & Meet the Teachers


Weekend Course

MSK Disease: Current Status & Potential Applications of Advanced Imaging - Morning

Organizers: Jung-Ah Choi, Emily McWalter, Riccardo Lattanzi, Miika Nieminen, Edwin Oei, Jan Fritz
Room 513A-C
Sunday 8:00 - 11:50
Moderators: Chiara Giraudo & Jan Fritz
8:00
Muscle Disorders: Diagnosis & Clinical Biomarkers
Pierre Carlier

.

8:25
Muscle Disorders: Emerging Biomarkers
Eric Sigmund

Outcomes/Objectives

·         Summarize quantitative biomarkers of skeletal muscle function (specifically relaxometry and diffusion-weighted imaging) that access novel physiologic properties

·         Describe the role of quantitative modeling for increased specificity

·         Describe examples of exercise as a controlled clinical challenge


8:50
MSK Complications of Diabetes: Present
Mark Schweitzer

1. Pathophysiology of DM

2. Why MSK system?

3. tendons

4. ligaments

5. joints

6. osteomyelitis


9:10
Self Assessment Module (SAM)

9:15
MSK Complications of Diabetes: Future
Prodromos Parasoglou

Individuals with long-standing diabetes are at high risk for developing devastating musculoskeletal complications including plantar ulcers, and Charcot arthropathy that can lead to amputation. A major obstacle for the development of effective treatments for musculoskeletal complications of diabetes is the lack of objective and reproducible tests to detect small changes in symptoms and signs seen in intervention studies. In this lecture, we will discuss how quantitative MRI methods can be help delineate the specific pathophysiological mechanisms that mediate the effectiveness of a treatment and identity patients who are responsive to an intervention. 

9:40
Break & Meet the Teachers

10:10
Inflammatory Arthropathy: Present
Tamotsu Kamishama

a

10:35
Inflammatory Arthropathy: Future
Chiara Giraudo

This lecture is for radiologists and clinicians, technologists, and scientists interested in musculoskeletal imaging with a special focus on inflammatory rheumatic diseases. The presentation will address how we may improve the diagnostic process in adults and pediatric patients affected by this heterogeneous group of inflammatory arthropathies. It will be discussed not only how the MR protocols can be further optimized considering the constant new technological improvements but also the role of hybrid imaging applying PET/MR. Indeed, PET/MR combining specific tracers and sequences via a whole-body approach may provide simultaneously acquired metabolic, functional and anatomical information characterizing the injured areas at diagnosis and after treatment. Furthermore, the role and application of qualitative and quantitative analyses will be addressed, including the use of machine learning and the assessment of radiomics features in the era of biological therapy.In conclusion, after this presentation, the audience should have a comprehensive overview about promising novel MR and PET/MR applications and the research aspectsthat should be further investigated in inflammatory arthropathies.

11:00
Osteoarthritis: Present
Alissa Burge

Osteoarthritis is an extremely common cause of morbidity, affecting an estimated 30.8 million adults in the united states, and is cited as the 5th most common cause of disability and the most prevalent form of musculoskeletal pathology worldwide, contributing to tremendous human and economic burden.  MR imaging can provide valuable information regarding a variety of characteristics relevant to the natural history of osteoarthritis, including risk factors, diagnosis and severity of disease, and complications of both disease and treatment, thereby facilitating clinical decision making.

11:25
Osteoarthritis: Future
Stefan Zbyn

Compositional MRI techniques have gained increasing attention in Osteoarthritis (OA) research over the recent years, as they allow detection of early biochemical alteration in musculoskeletal tissues prior to appearance of the morphological changes. This presentation will provide an overview of basic technical principles, biochemical correlates, recent technical developments and in vivo applications of compositional MRI techniques for early detection, monitoring and prediction of OA progression in the knee joint.

11:50
Lunch & Meet the Teachers


Weekend Course

RF Coils

Organizers: Gregor Adriany, Mary McDougall
Room 516AB
Sunday 8:00 - 16:00
Moderators: Greig Scott & Manuela Rösler
8:00
Basics of RF Theory, Transmission Lines & Power Transfer
Steven Wright

This talk will cover the basics of RF transmission lines and wave guidance.  While two-conductor transmission lines are ubiquitous in MRI today, other forms of wave guidance are becoming increasingly popular with the emergence of high and ultra-high field MRI systems. An electromagnetic approach to transmission lines, as opposed to a circuit-theory approach, covers all cases.  The talk will discuss the Smith Chart, applications of transmission lines beyond interconnects, and discuss practical issues of transmission line selection.

8:30
Volume & Surface Coils
Özlem Ipek

This talk will cover the basic theory and design of a RF coil, characterization of the RF coil on the bench including tuning, matching and quality factor with a vector network analyzer, on the scanner with B1 maps and signal-to-noise ratio measurements and electromagnetic field simulations. Various types of RF coils as well as the recent RF coil concepts will be addressed. 

9:00
Multi-Tuned Coils
Ryan Brown

·       Dual-tuned coils provide metabolic information (x-nuclei module) and co-registered anatomical images and B0 shim settings (1H module) without repositioning the subject or coil

·      X-nuclei signal strength is typically less than 1/1,000× that of 1H (1). Therefore it is important to maximize x-nuclei receive sensitivity while simultaneously providing adequate 1H sensitivity

·       We will discuss prevalent dual-tuning techniques and considerations for performance characterization and interfacing dual-tuned coils


9:30
Break & Meet the Teachers

10:00
Receive Arrays & Circuitry
Arne Reykowski

Transmit antennas are typically design with a strong focus on homogeneity. In contrast, receive antennas (also referredto as local coils) are optimized for high signal-to-noise ratio (SNR) within a certain region of interest (ROI) andtypically do not offer homogeneous sensitivity.

10:30
Transmit Arrays & Circuitry
Roberta Frass-Kriegl

RF transmission in MR measurements relies on RF coils, the transmit system (typically part of the MR scanner), and RF pulse design. In this educational presentation, basic principles of transmit coil arrays and related circuitry will be explained for single channel as well as multi-channel transmit systems. The potential of static B1+ shimming and full parallel RF transmission will be discussed including the aspect of more complicated safety evaluation in terms of specific absorption rate (SAR) with increased degrees of freedom.

11:00
RF Modeling
Bastien Guerin

In this talk, I will present the basics of the three main electromagnetic simulation approaches for assessment of MRI RF coils: finite difference time domain, finite element modeling and integral equations. The strengths and weaknesses of these techniques will be compared. I will introduce the co-simulation approach to fast coil analysis. Finally, I will talk about the availability of body models for each technique as well as major applications such as RF coil safety assessment, design optimization and calculation of ultimate metric bounds.

11:30
Lunch & Meet the Teachers

13:30
RF Coils & Materials at High Fields
Andrew Webb

This talk concentrates on the similarities and differences in designing RF coils for high field MRI. In particular the effects of sample loading, coil losses, coil decoupling, travelling wave effects and near field/far field effects are considered. Examples of loop, dipole and combined loop/dipole configurations are shown. Finally the role of high permittivity materials, alone or in combination with high field MRI coils is discussed. 

14:00
Emerging Technologies: Flexible, Lightweight, Optical & Wireless
Fraser Robb

Phased coil arrays have changed dramatically since their earliest inception with increasing complexity and channel density. These changes have led to the development of an innovative fully flexible coil design with highly integrated electronics, which can be placed easily within todays modern coil arrays to reduce the design complexity associated with the large number of channels. Recently, research has been done to improve the interface between RF coils and MRI systems by transferring the data over wireless or optical connections within the scanner bore. The evolution of all of these new technologies can provide a fully wireless, or lightly tethered, future for coil arrays and allow potential the realization of a patient-friendly phased array.

14:30
Break & Meet the Teachers

15:00
Live Construction of Receive Arrays
Kyle Gilbert

This course will focus on the construction of a four-channel receive array for small-animal imaging at 9.4 T. Although this demonstration is geared toward a specific application, the construction methods are applicable to receive arrays for both humans and animals, and with any number of elements. The demonstration will cover the basic steps of constructing a receive array: the design of a former, tuning and matching, preamplifier decoupling, active detuning, geometric decoupling, and cable management. This course is intended for the student, technician, or researcher who wants to learn the basic steps on how to build a receive array.

15:00
Live Construction of Receive Arrays
Omer Oran

16:00
Adjournment & Meet the Teachers


Weekend Course

Neurofluids & Brain Lymphatics: From Bench to MRI

Organizers: Nivedita Agarwal, Kei Yamada
Room 516C-E
Sunday 8:00 - 11:50
Moderators: Nivedita Agarwal & Kei Yamada
8:00
Basic CNS Fluid Physiology
Andreas Linninger

Keywords: cerebrospinal fluid flow, intrathecal drug delivery, intracranial dynamics,

8:25
Interacting Fluid Compartments of the Central Nervous System: A Holistic Mathematical Modelling Approach
Eleuterio Toro

We first describe all major fluid compartments of the central nervous system, their connections and their relevance to understand some neurological diseases. We then present a full-body, global mathematical model for the fluid dynamics includind heart, pulmonary circulation, respiration, arterial and venous trees, miscrovasculature, brain parenchyma and cerebrospinal fluid, We outline the equations and algorithms to solve these on a computer to produce subject-specific predictions. Validation of predictions against MRI measurements and is presented. We then apply the methods to study intra and extracranial venous outflow anomalies and their impact on cerebral haemodynamics in terms of increased intracranial pressure, reverse flow, altered shear stresses, altered fluid transport, altered perfusion. 

8:50
Role of Fluid Dynamics in Neurological Diseases
E. Mark Haacke

9:15
MR Imaging of CSF Spaces
Shigeki Yamada

We have studied how to visualize “neurofluids” three-dimensionally by using transparency and perspective technologies with shading and texture mapping from volumetric magnetic resonance imaging. The mean volume of the intracranial cerebrospinal fluid (CSF) in healthy individuals aged ≥70 years was estimated at more than 300 mL. CSF movement with cardiac pulsation was reduced with increasing age, although the dynamics of neurofluids has not been elucidated. By developing fluid dynamics-related technology, the 3D movement of CSF can be measured quantitatively. CSF dynamic theory has been renewed; the CSF does not exhibit unidirectional bulk flow and moves in a pulsatile fashion.


9:40
Break & Meet the Teachers

10:10
Mechanisms of Brain Drain: Glymphatics
Helene Benveniste

The glymphatic system (GS) is described as a perivascular transit passageway for cerebrospinal fluid (CSF) and interstitial fluid exchange that facilitate metabolic waste drainage from the brain in a manner dependent on aquaporin 4 (AQP4) water channels on glial cells and vascular pulsatility. In this presentation I will present the fundamentals of the GS concept (including current controversies) and focus on MRI methods to quantify GS transport in normal and diseased brain. Evidence for its existence in human brain will also be highlighed.

10:35
Drainage of fluids from the brain
Roxane Carare

Interstitial fluid of the brain drains along the walls of capillaries and arteries as intramural periarterial drainage (IPAD). This process fails with ageing and possession of APOE4 genotype, resulting in cerebral amyloid angiopathy (CAA). There is convective influx/glymphatic entry of cerebrospinal fluid (CSF) along the pial glial basement membranes into the brain parenchyma.

11:00
From Magnetic Resonance to Mathematical Models for Flow Dynamics
John Vardakis

11:25
Imaging Brain Lymphatics
Toshiaki Taoka

In recent years, mass transport system in the brain by cerebrospinal fluid or interstitial fluid has been clarified from the researches until now. Glymphatic system is the waste clearance pathway system by cerebrospinal fluid through perivascular space and interstitial space in the brain. To visualize or evaluate the waste clearance system of the brain, tracer studies are mostly applied and findings on the system has been accumulated. There are several approaches other than tracer studies to evaluate the dynamics of the interstitial fluid within the brain including diffusion images. Findings from these studies will be discussed in this lecture.

11:50
Lunch & Meet the Teachers


Weekend Course

Vascular Educational

Organizers: Winfried Willinek, Neville Gai
Room 518A-C
Sunday 8:00 - 12:00
Moderators: Giles Roditi & Oliver Wieben
8:00
Contrast Agents
Tim Leiner

8:30
Non-Contrast Enhanced
Mitsue Miyazaki

Various established non-contrast enhanced MRA techniques such as time-of-flight (TOF), quiescent interval single-shot (QISS), fresh blood imaging (FBI), and a flow-in spin labeling are discussed with their characteristic features. In addition, recent on-going research techniques are introduced such as flow-sensitive dephasing (FSD), velocity-selective inversion preparation with 3D bSSFP, radial QISS, and radial fast interrupted steady-state (FISS).

9:00
Contrast-Enhanced
Jeremy Collins

Contrast-enhanced MR angiography is an adaptable imaging technique that can be tailored to the clinical question posed. CE-MRA relies on subtracted and unsubtracted techniques applied to single station, multi station, and time-resolved CE-MRA. CE-MR Angiography is considered a reference standard for arterial evalation. More recent developments rely on imaging in the steady state with ECG-gating, applying acceleration schema to shorten imaging time without compromising the spatial resolution.

9:30
Flow Hemodynamics
Susanne Schnell

Phase contrast MRI and its utilization to measure blood flow will be explained. Spins that move during an MRI acquisition exhibit different imaging characteristics compared to stationary spins. Flowing spins, for example from flowing blood, appear as an artifact in the image. However, by understanding these characteristics of flowing spins, their appearance can be utilized for angiographic purposes. 2D Phase contrast imaging is sensitized to flow by using a series of bipolar gradients to affect the phase signal of spins that flow with a uniform velocity in the direction parallel to the gradients. By utilizing ECG gating, blood flow velocities can be measured in a time-resolved manner. 2D phase contrast can be extended to a time-resolved 3D volume acquisition with 3-directional velocity encoding, which is called 4D flow MRI. This encoding of velocity enables quantification of flow hemodynamics. Furthermore, some potential sources of error will be discussed, such as misalignment of flow, velocity aliasing and phase offset errors.

10:00
Break & Meet the Teachers

10:30
Supraaortic & Intracranial
Bum Soo Kim

This talk will describe the sequences used for MRA of intracranial and supraaortic vessels, and clinical application to cerebrovascular diseases, focusing on the contributions that MRA can make to diagnosis and follow-up. 

11:00
Chest & Abdominal
Mark Schiebler

This syllabus and the accompanying slides serve as an introduction to the use of pulmonary MRA for the primary diagnosis of pulmonary embolism. It is our hope that you will be able to start up a program at your institution based on this information.

11:30
Peripheral
Trisha Roy

This peripheral arterial educational session will review the pathophysiology and management of peripheral arterial disease, current imaging modalities, gaps in knowledge and opportunities for MRI to address the many remaining questions in this field. 

12:00
Lunch & Meet the Teachers


Weekend Course

MRI Data Acquisition: Pulse Sequences

Organizers: Fernando Boada, Douglas Noll, Neville Gai
Room 520A-F
Sunday 8:00 - 11:30
Moderators: Xiaohong Joe Zhou & Suchandrima Banerjee
8:00
RF Excitation & Parallel Transmission
William Grissom

RF excitation is a necessary ingredient to all pulse sequences. This lecture will introduce common RF pulse types, the mechanics behind their function, and practical uses for them. The goal of this lecture is to give the pulse sequence designer the knowledge necessary to make appropriate RF pulse selections in a wide variety of applications.

8:30
Signal Generation & Spatial Encoding
David Higgins

Basic MR physics will be reviewed, to provide a foundation for discussion of more advanced concepts in the course. The process of spatial encoding of the MR signal, from signal generation to image reconstruction, will be described. The the information content of k-space will be illustrated and discussed. Routine adjustments which are made to k-space data will be introduced.

9:00
Encoding Basic Physiological Processes into the MRI Signal: Motion & Flow
Pelin Aksit Ciris

MRI can be used to non-invasively encode and quantify different biophysical aspects of tissue including flow and motion. In this presentation, we will review methods that generate motion related image contrast, through manipulation of longitudinal magnetization prior to excitation, such as Time-of-flight MR Angiography, Arterial Spin Labeling, Myocardial Tagging; as well as through manipulation of transverse magnetization between excitation and acquisition, such as Phase Contrast MR Angiography, Diffusion Imaging, and MR Elastography.

9:30
Break & Meet the Teachers

10:00
Single-Shot Sequences
Xiaohong Joe Zhou

Single-shot pulse sequences are a class of sequences that can rapidly traverse k-space in a single repetition time (TR), producing sufficient k-space data for image reconstruction. In this lecture, we will highlight four single-shot pulse sequences, including echo planar imaging (EPI), turbo-spin echo (TSE) or fast spin echo (FSE), gradient and spin echo (GRASE), and spiral. For each pulse sequence, we will describe the spin physics involved, discuss several “tricks” in practical implementation, present strategies to mitigate image artifacts, and provide examples in clinical and research applications. 

10:30
Multi-Shot & Multi-Echo Techniques
Daniel Herzka

11:00
Faster & Higher Quality MRI Through Tailored Undersampling
Kawin Setsompop

Various image reconstruction approaches (e.g. parallel imaging, CS, ML) have been developed to enable k-space under-sampling. Optimal performance for these reconstruction approaches at high accelerations requires a tailored sampling scheme. In this course, we will examine these sampling strategies and how to adopt them effectively in a wide variety of imaging sequences under various constraints. Insights on how to flexibly take advantage of the undersampling for either scan time reduction and/or artifact mitigation will be discussed. Examples will be provided to demonstrate the benefit of a synergistic design approach on sampling, sequence, and reconstruction. 

11:30
Lunch & Meet the Teachers


Weekend Course

Open-Source Software Tools for MR Pulse Design, Simulation & Reconstruction

Organizers: Michael Lustig, Tony Stoecker, Lawrence Wald
Room 710B
Sunday 8:00 - 16:00
Moderators: Daniel Gallichan & Valentina Taviani
8:00
Bloch Simulation & Pulse Sequences Tools
Maxim Zaitsev

8:25
Designing Reusable Software Components for Computational MRI
Martin Uecker

Computational techniques play an important part in the development of new methods for Magnetic Resonance Imaging (MRI). Based on our experience developing software for computational MRI, this talk will explain how to develop reusable software components that preserve our scientific knowledge in a reproducible, useful, and sustainable way.

8:50
Usinig cloud computing for exploration and scale
Eric Jonas

The rise of “cloud computing” offerings has enabled many recent advances in data science, simulation, and data analytics. Current cloud providers offer a previously-unimaginable combination of scale, storage, and compute capabilities but it can be difficult for a newcomer to navigate the ecosystem. This tutorial session is targeted at developers and users who have not used cloud computing infrastructure before, or have only recently started experimenting. I will outline the offerings from the various providers, compare and contrast their capabilities, and show how they can enable rapid experimentation and analysis at very low cost. I will highlight several open-source projects, developed by my research group and others, to make this onboarding process easier. I will point out some common pitfalls from migrating existing workloads to the cloud, and suggest means of avoiding them.

9:15
Open-Source Reconstruction Systems
Adrienne Campbell-Washburn

This talk will summarize the features of open source MR image reconstruction software projects and provide illustrative examples of software usage. 

9:40
Break & Meet the Teachers

10:10
MRiLab: Realistic MRI Simulations Based on Parallel Computing & Generalized Tissue Model
Fang Liu

10:18
JEMRIS: A General-Purpose MRI Simulator
Daniel Pflugfelder

10:27
The KSFoundation Abstraction Layer for EPIC
Stefan Skare

10:35
gammaSTAR: Platform-Independent MR Sequence Development
Cristoffer Cordes

10:43
Live Cross-Vendor Sequence Programming with Pulseq
Maxim Zaitsev

10:52
RF & Gradient Optimization Tools
John Pauly

11:00
Yarra Framework: Open-Source Toolkit for Clinical-Translational MRI Research
Roy Wiggins

11:08
Automated Reconstruction Handling
Eric Borisch

11:17
MRIReco.jl: An Extensible Open-Source Image Reconstruction Framework Written in Julia
Tobias Knopp

11:25
BART Reconstruction Toolbox / Iterative Reconstruction Toolbox in Python
Jonathan Tamir

11:33
Gadgetron
Hui Xue

11:42
GPILAB
Nicholas Zwart

11:50
Lunch & Meet the Teachers

13:30
Hands - On Demonstrations

16:00
Adjournment & Meet the Teachers


Weekend Course

Basic Perfusion

Organizers: Fernando Calamante, Hanzhang Lu, Jongho Lee
Room 710A
Sunday 8:00 - 11:50
Moderators: Hanzhang Lu & Shin-Lei Peng
8:00
ASL Acquisition methods
Luis Hernandez-Garcia

This segment of the course will introduce the audience to the main varieties of arterial spin labeling schemes, as well as the practical considerations and options for image readouts.  The technical details and practical considerations for implementation will be discussed from an engineering point of view.

8:25
ASL: Analysis
Laura Parkes

ASL acquisition produces perfusion-weighted images through the subtraction of label and control images. These may be collected at a single post-labelling delay time or at multiple delay times. How do we extract quantitative CBF from these subtraction images? Quantification is important as the signal in the perfusion-weighted images will be affected by parameters other than blood flow, principally arterial transit time, labelling efficiency and the T1 and equilibrium magnetisation of blood. These may vary on an individual and/or regional basis. In this talk I will describe the most widely used method for quantification (Alsop et. al. 2015) and explain which parameters are most important for CBF accuracy.

8:50
ASL: Advances
Lirong Yan

Multiple physiological parameters other than CBF can be derived from ASL signal when the magnetically labeled blood passes through arterial trees and freely diffuses across the blood-brain barrier in capillaries, such as dynamic MR angiography, arterial cerebral blood volume (aCBV), vascular compliance (VC), and water permeability. This lecture will cover these recently developed advanced ASL techniques.  

9:15
ASL: Reproducibility, Multi-Site & Validation
Henk Mutsaerts

This lecture focuses on the reproducibility of arterial spin labeling (ASL). Several interconnected factors influence the reliability of ASL. Mainly, investigators should strive to keep sequence parameters as identical as possible between different ASL datasets, whether this concerns a single-center scanner software update or pooling of different multi-center ASL datasets. Second, the consistency of ASL quantification parameters between sequences should be validated, for which the ASL-BIDS format is introduced. Third, it is important to acknowledge how (patho-)physiology determines the reliability of ASL. Finally, the definition of ASL image quality and recognition of artifacts should be standardized.  

9:40
Break & Meet the Teachers

10:10
DSC-MRI: Acquisition
Jerrold Boxerman

DSC-MRI has been used in the brain since the early 1990s, (1,2) with multiple applications to gliomas, including treatment response assessment. (3) However, incorporation into multi-center clinical trials has been limited. This presentation briefly summarizes DSC-MRI acquisition methodology; the need for standardizing DSC-MRI for multi-site trials, as illustrated by application to pseudoprogression (PsP) and pseudoresponse (PsR); (4-6) and ongoing efforts to achieve this goal.

10:35
DCE-MRI: Acquisition
Chad Quarles

The overall purpose of this educational lecture is to discuss conventional and state-of-the-art acquisition methods for DCE-MRI. Topics will include protocol design informed by contrast mechanisms, sensitivity and spatiotemporal demands and advances in DCE-MRI acquisition methods based on technological advances (e.g. novel sampling schemes) and designed to enhance sensitivity to a greater range of physiologic properties. 

11:00
DSC-MRI: Analysis
Ona Wu

Learn how to make perfusion maps and understand potential confounds.

11:25
DCE-MRI: Analysis
Linda Knutsson

This educational presentation gives an overview how to analyse data obtained from a Dynamic Contrast Enhanced (DCE) MRI experiment in order to retrieve perfusion and/or perfusion-related parameters.

11:50
Lunch & Meet the Teachers


Weekend Course

Gynecology

Organizers: Reiko Woodhams, Utaroh Motosugi
Room 512A-H
Sunday 13:30 - 14:50
Moderators: Evis Sala & Reiko Woodhams
13:30
Congenital Anomaly
Aki Kido

Müllerian duct anomalies (MDAs) are broad spectrum of developmental anomalies and its classification system is proposed by American Society for Reproductive Medicine. Ultrasound and Hysterosalpingography are the initial modalities, but MRI is superior by its high soft tissue contrast and multiplanar imaging capabilities. Accurate classification of MDAs is important as surgical treatment may varies among MDA subtypes. In this lecture, each type of MDAs are overviewed with embryological aspect and imaging findings will be explained with actual cases with MR images.

13:50
Cervical & Endometrial Cancer
Caroline Reinhold

This presentation will review the role of MRI in the staging of endometrial and cervical carcinoma, present the 2018 FIGO staging updates for cervical carcinoma, review the imaging protocol and briefly present future directions.

14:10
Acute Gynecologic Disease
Victoria Chernyak

This presentation will review MRI appearance of acute gynecologic conditions, both in pregnant and nonpregnant patients.

14:25
Self Assessment Module (SAM)

14:30
Endometriosis
Nicole Hindman

Endometriosis is a common but occult cause of chronic pelvic pain in women.  Being able to recognize the appearance and spectrum of endometriosis, particularly deep infiltrating endometriosis, on MR imaging offers incredible value to referring physicians.  This talk will review the typical and unusual appearances of deep infiltrating endometriosis on MRI.

14:50
Break & Meet the Teachers


Weekend Course

MSK Disease: Current Status & Potential Applications of Advanced Imaging - Afternoon

Organizers: Jung-Ah Choi, Jan Fritz, Riccardo Lattanzi, Emily McWalter, Edwin Oei, Miika Nieminen
Room 513A-C
Sunday 13:30 - 15:40
Moderators: Eric Chang & Marianne Black
13:30
Sports Injuries: Present
Haron Obaid

This talk will focus on MRI imaging techniques as related to sports injuries, role of MRI in sports imaging-problem solving tool, pitfalls and limitations of MRI in sports imaging. There will be a review of imaging findings of common injury patterns affecting the tendons, ligaments, cartilage, muscles and bones.

13:55
Sports Injuries: Advanced Imaging Methods for Injuries to Short-T2 Tissues
Ashley Williams

Sprains, strains, tears and stress fractures are unfortunately common occurrences in athletes and weekend warriors alike.  Detection and quantitation of subtle and, in some cases, subclinical damage to short-T2 tissues using advanced MRI methods, like ultrashort echo time (UTE) and zero echo time (ZTE) imaging, may help to guide the clinical management of injured patients as they recover and return to sport. Audience members will be introduced to common sports injuries involving short-T2 tissues and new and upcoming MRI techniques to diagnose, stage, and monitor tissue injury and recovery by assessing short-T2 tissue properties.

14:20
Break & Meet the Teachers

14:50
Osteonecrosis & Osteochondrosis: Present
Mihra Taljanovic

This talk reviews the pathophysiology, clinical findings, imaging findings and treatment options of epiphyseal osteonecrosis, bone infarcts and various types of osteohondroses with emphasis on magnetic resonance imaging (MRI). Specifically, osteonecrosis of the femoral head, humeral head, talar dome, lunate and proximal scaphoid pole will be discussed. Steinberg modified FICAT classification of the femoral head osteonecrosis and Lichtman staging of Kienbock Disease will be presented in tables. Following osteochondroses will be addressed:  Legg-Calvé-Perthes disease, osteochondritis dissecans (OCD), osteochondrosis of the capitellum (Panner disease), Blount disease (tibia vara) Osgood-Schlatter disease, Sinding-Larsen-Johansson disease (jumper’s knee), Freiberg infraction, Köhler disease and Scheuermann’s disease.

15:15
Osteochondrosis & Osteonecrosis: Future Musculoskeletal Imaging Applications for Pediatric and Young Adult Patients
Jutta Ellermann

Advanced qualitative and quantitative MRI methods can be utilized to study unique aspects of the developing skeleton that are important for diagnosis and better treatment of musculoskeletal diseases of pediatric and young adult patients.

15:40
Adjournment & Meet the Teachers


Weekend Course

CNS Tumors

Organizers: Meiyun Wang, Christopher Hess
Room 516C-E
Sunday 13:30 - 16:55
Moderators: Kei Yamada & Ovidiu Andronesi
13:30
The WHO 2016 Classification of Brain Tumors
Ulrike Löbel

Major restructuring occurred in the 2016 classification of brain tumors. All diffuse astrocytic and oligodendroglial tumors are now grouped together and oligodendrogliomas are defined by a 1p/19q-codeletion. The new entity of diffuse midline glioma predominates in children and is characterized by a very poor outcome. Within the group of embryonal tumors, the current classification defined medulloblastoma WNT–activated and medulloblastoma SHH–activated as tumor entities and the new entity of embryonal tumour with multilayered rosettes (ETMR), C19MC-altered was defined. On the other hand, the term primitive neuroectodermal tumor (PNET) was removed from the tumor classification.

13:55
Use of Intraoperative MRI for Improvement of Neurosurgical Intervention
Akira Matsumura

Intraoperative MRI (i-MRI) is a powerful tool in improving the surgical intervention for brain and skull base surgery. We would like to share our experience of tha advantage of using i-MRI for better treatmet results.


14:20
Spinal Cord Tumors
Carlos Torres

14:45
Break & Meet the Teachers

15:15
Pediatric Tumors
Benita Tamrazi

Advanced imaging of pediatric brain tumors will be discussed with emphasis on clinical scenarios.

15:35
Self Assessment Module (SAM)

15:40
Radiomics in Gliomas
Yoon Seong Choi

16:05
Molecular Imaging
Georges El Fakhri

16:30
Tumor Therapy
Marco Essig

Brain tumours are among the top causes of cancer related deaths both in Europe and North America.  The goals and requirements for neuroimaging in brain tumours are multiplex and involve making a diagnosis and a differential diagnosis, while accurate lesion grading is needed in the case of the overall patient management.  Imaging is also involved in the decision-making process for therapy and later for precise planning of surgical or radio-therapeutic interventions. After therapy neuroimaging techniques have shown to be mandatory for monitoring of disease and detection as well as management of possible therapy related side effects. 

16:55
Adjournment & Meet the Teachers


Weekend Course

Cardiac MR: Linking Physiology to Imaging

Organizers: Tim Leiner, Bernd Wintersperger
Room 518A-C
Sunday 13:30 - 16:30
Moderators: Andrew Scott & Byoung Wook Choi
13:30
Cardiac Physiology & Electrophysiology: Beginners' Guide
Saman Nazarian

Summary slide set for Dr. Nazarian's talk on: "CARDIAC MR: LINKING PHYSIOLOGY TO IMAGING".

13:55
Cardiac & Myocardial Function
Ru San Tan

Cardiac MR images contain rich 4-D spatio-temporal information that have been largely unexploited in routine image interpretation. Feature-tracking as well as other novel post-acquisition analyses of these images have potential to yield clinical meaningful readouts that can allow detailed dissection of heart chamber global and regional, systolic and diastolic, function.

14:20
Imaging of Myocardial Perfusion & Scar
Kate Hanneman

Imaging of Myocardial Perfusion & Scar

14:45
Break & Meet the Teachers

15:15
Advanced Contrast Mechanisms: Diffusion & DTI of the Heart
Christopher Nguyen

Diffusion MRI is powerful tool to interrogate the myocardial microstructure revealing fiber architecture. Technical advances in the past 5 years have enabled in vivo free breathing diffusion MRI of the heart and is primed to make new discoveries in patient populations as an orthogonal quantitative tool alongside conventional methods such as relaxometry mapping and function.

15:35
Self Assessment Module (SAM)

15:40
Augmented Intelligence & Radiomics in Cardiac MRI
Bettina Baessler

Augmented intelligence and radiomics will play an important role in future cardiac MR. Techniques like machine learning or deep learning will influence all aspects of cardiac MR, from patient management and workflow over image acquisition and reconstruction up to image analysis and prognostic assessment. This presentation will focus on current applications of AI and radiomics in cardiac MR and address the limitations of these techniques before their integration into routine clinical practice becomes reality.

16:05
Benefits & Challenges of Cardiac Relaxometry
Donnie Cameron

Cardiac relaxometry permits quantitative characterisation of myocardial tissue. Over the past fifteen years, it has grown from obscure research method to routine clinical tool, offering strong diagnostic and prognostic utility in some conditions. The goals of this session are to: (i) outline the key benefits of cardiac relaxometry methods with respect to clinical applications; (ii) describe the methodological details of cardiac relaxometry techniques, including T1, T2, T2*, and T1-rho mapping; and (iii) summarise current pitfalls of relaxometry methods in terms of acquisition, processing, and interpretation.

16:30
Adjournment & Meet the Teachers


Weekend Course

MRI Image Reconstruction: Nyquist & Non-Nyquist Techniques

Organizers: Fernando Boada, Douglas Noll, Neville Gai
Room 520A-F
Sunday 13:30 - 16:30
Moderators: Ricardo Otazo & Suchandrima Banerjee
13:30
Spatial Encoding & Direct Inversion of Cartesian & Non-Cartesian Data
Nicole Seiberlich

13:55
Parallel Imaging
Tolga Cukur

A brief survey of the fundamental approaches to parallel imaging will be presented, followed by recent application to multi-acquisition or multi-parametric MRI.

16:05
Compressed Sensing
Jonathan Tamir

Compressed sensing takes advantage of sparsity, incoherent sampling, and non-linear reconstruction algorithms to reduce acquisition requirements far below the Nyquist rate. This talk will provide an overview of these concepts and show how they can be used to accelerate MRI. Compressed sensing MRI examples will be discussed, including its combination with parallel imaging and application to dynamic imaging.

14:45
Break & Meet the Teachers

14:20
Low Rank Plus Sparse Reconstruction
Jong Chul Ye

In this course, we will review the recent MR researches using low rank and sparse reconstruction. First, basic compressed sensing theory for  MR reconstruction method is first reviewed, after which the low-rank image model is described. Finally, sparse + low rank model is introduced as an novel image modeling for accelerated MRI and artifact removal.

15:15
Using Machine Learning for Image Reconstruction
Florian Knoll

This talk will provide an introduction to the use of machine learning and convolutional neural networks (CNNs) in the area of MR image reconstruction from undersampled acquisitions. We will discuss approaches that are based on iterative reconstruction methods that are commonly used in compressed sensing (CS) as well as purely data driven approaches. Using selected examples, we will discuss both advantages and challenges, covering topics like reconstruction time, design of the training procedure, error metrics and training efficiency and validation of image quality.

15:40
Practical Implementation of Efficient Off-Line Image Reconstruction Pipelines
Hui Xue

16:30
Adjournment & Meet the Teachers


Weekend Course

Brain Connectivity: Structure & Function

Organizers: Fernando Calamante, Jongho Lee
Room 710A
Sunday 13:30 - 16:30
Moderators: Masaki Fukunaga & Patricia Figueiredo
13:30
How the Brain Is Connected
David Van Essen

Recent studies of long-distance connections in the cerebral cortex reveal that they are remarkably complex, but major insights have been learned using anatomical tracers in monkeys and mice and noninvasive neuroimaging in humans and monkeys.

13:55
Introduction to Functional Connectivity
Zhongming Liu

This talk will serve as an introduction to functional connectivity. The primary focus is on spontaneous brain activity observed with functional magnetic resonance imaging. In this talk, I will cover the origins of resting state fMRI signals, analysis methods to map large-scale functional brain networks based on fMRI (or MEG/EEG), dynamics of functional connectivity, variation of functional connectivity across brain states, diseases, or individuals, as well as some recent work of using deep learning to map or analyze functional connectivity.  

14:20
Introduction to Structural Connectivity
Maxime Descoteaux

Introductory course for people seeking to learn about the fundamental of structural connectivity and building the “connectome” using diffusion MRI tractography.

14:45
Break & Meet the Teachers

15:15
Connectomics: Data Analysis
Sarah Genon

Connectomics analyses play a major role in our understanding of the human brain organization and function. In this talk, I will present the concepts, methods and applications of a widely used approach to examine brain organization: connectivity-based parcellation (CBP). I will then introduce the concepts and methods of connectivity-based psychometric prediction as an approach capitalizing on interindividual variability in brain and behavior to study the relationship between brain organization and behavioral functions. I will here focus on the prediction of psychometric data based on resting-state functional connectivity (rs-fMRI).

15:40
Linking Structural & Functional Connectivity: Methods & Modeling
Richard Betzel

The human brain can be modeled as a set of white-matter fibers (structural connectivity; SC) that constrain inter-regional interactions and shape the correlation structure of brain activity (functional connectivity; FC). Though SC and FC capture distinct connectional modes, they can both be modeled as networks. Understanding their relationship to one another is critical for if we wish to deepen our knowledge of the role networks place in cognition, health, and development. In this talk I will review current approaches for linking SC with FC, emphasizing that there exists a spectrum of approaches, each suited for answering specific research questions.

16:05
Multimodal Fusion: Exploiting links among enriched types of imaging, cognitive and behavioral information
Jing Sui

Psychiatric imaging is struggling with identifying robust biomarkers. Existing approaches do not fully leverage the power of multimodal data, despite evidence that such information is highly informative.  We will draw on advances and ideas from fields of supervised learning,data fusion and deep learning, to capture rich information from imaging, cognitive, behavioral and genetic data, in order to integrate a whole picture to deepen our understanding of neural mechanism of  cognitive impairment, and to identify replicable biomarkers that are able to predict individual clinical measures and help for differential diagnosis and intervention.

16:30
Adjournment & Meet the Teachers


Weekend Course

Bowel

Organizers: Kartik Jhaveri, Kathryn Fowler, Utaroh Motosugi
Room 512A-H
Sunday 15:20 - 16:40
Moderators: Caroline Reinhold & Mary-Louise Greer
15:20
Rectal Cancer Staging
Akira Furukawa

MRI diagnosis of rectal cancer will be reviewed regarding 1) Anatomy of the rectum and per-rectal structure, 2)MR imaging technique for preoperative assessment of rectal cancer, 3) Important MR findings in preoperative assessment of rectal cancer, 4) Diagnostic accuracy of MR in rectal cancer. 

15:40
Rectal Cancer Post-Treatment Assessment
Gina Brown

  TARGET AUDIENCE

Radiologists with an interest in cancer imaging who would benefit from: ·         Understanding the role of high-resolution MRI reassessment following chemoradiotherapy. ·         How this information can improve outcomes by providing important prognostic and therapeutic information.


16:00
Perianal Fistula MRI
Mukesh Harisinghani

MRI is useful modality to assess the surgical anatomy of anorectal fistulas. The information gathered from MRI influences the surgical approach and overall treatment.

16:20
MR Enterography
Jonathan Dillman

MR enterography is critical to the diagnosis and continued assessment of children and adults with Crohn’s disease. In this talk, we will review how radiologists can maximize value when performing MR enterography through: 1) Standardized reporting, including meaningful impression statements, 2) Accurate assessment of intestinal inflammatory activity and therapy response, and 3) Detection and accurate characterization of Crohn’s disease-related complications and extra-intestinal manifestations.

16:40
Adjournment & Meet the Teachers


Plenary Session

Lauterbur Lecture: My Life in Magnetic Resonance: Sense & Serendipity

Plenary Hall - Room 517
Sunday 17:00 - 18:15
17:00
Welcome
Pia Maly Sundgren

17:30
My Life in Magnetic Resonance: Sense & Serendipity
Peter van Zijl


Evening Event

ISMRM Opening Reception

Exhibition Hall
Sunday 18:30 - 20:00
(no CME credit)


Monday, 13 May 2019

Go to top
Sunrise Session

fMRI in the Clinic

Organizers: Hanzhang Lu, Susan Francis, Benedikt Poser, Richard Buxton
Room 510A-D
Monday 7:00 - 8:00
Moderators: Hanzhang Lu & Xiaoqi Huang
7:00
fMRI Applications in Brain Diseases
Nicolas Ramsey

7:30
fMRI in Surgical Planning
Joshua Shimony

8:00
Adjournment


Sunrise Session

Imaging Without Gadolinium: ASL

Organizers: Pia Maly Sundgren, Elna-Marie Larsson, Robert Witte
Room 511BCEF
Monday 7:00 - 8:00
Moderators: Qin Qin & Robert Witte
7:00
ASL: Technique
Matthias J.P. van Osch

7:30
Clinical Applications of ASL in the Brain
Marion Smits

8:00
Adjournment


Sunrise Session

Multinuclear Imaging & Spectroscopy: Electrolytes (Sodium & Beyond)

Organizers: Ronald Ouwerkerk, Wolfgang Bogner
Room 512A-H
Monday 7:00 - 8:00
Moderators: Rob Stobbe & Manuela Rösler

Sunrise Session

Preclinical MRI: Methods & Applications: Neuroimaging

Organizers: Ed Wu, Elena Vinogradov, Lucio Frydman, Damian Tyler, Elena Kaye
Room 513A-C
Monday 7:00 - 8:00
Moderators: Damian Tyler & Alex T. L. Leong
7:00
Basic Brain MRI Methods
Kevin Chan

7:30
Advanced Brain MRI: Functions & Circuits
Joanes Grandjean

8:00
Adjournment


Sunrise Session

Quantitative MRI: Relaxometry

Organizers: José Marques, Sebastian Kozerke, Ileana Hancu
Room 513D-F
Monday 7:00 - 8:00
Moderators: José Marques & Sebastian Kozerke

Sunrise Session

Cardiovascular MR of the Future: Hardware

Organizers: Bernd Wintersperger, Tim Leiner
Room 516AB
Monday 7:00 - 8:00
Moderators: Tobias Schaeffter
7:00
New Developments in Coils for Cardiovascular MR
Martijn Froeling

7:30
Opportunities of Low-Field MR
Rizwan Ahmad

8:00
Adjournment


Sunrise Session

Advanced MSK MRI Acquisition & Post-Processing: Machine Learning

Organizers: Jung-Ah Choi, Miika Nieminen, Edwin Oei, Jan Fritz
Room 516C-E
Monday 7:00 - 8:00
Moderators: Victor Casula & Akshay Chaudhari
7:00
Machine Learning: Research Perspective
Fang Liu

7:30
Machine Learning: Clinical Perspective
Richard Kijowski

8:00
Adjournment


Sunrise Session

Why Do My Body Images Look So Bad?

Organizers: Utaroh Motosugi, Vikas Gulani
Room 518A-C
Monday 7:00 - 8:00
Moderators: Ananya Panda & Elizabeth Hecht
7:00
Liver
Hersh Chandarana

7:30
Pelvis
Brian Hargreaves

8:00
Adjournment


Digital Poster: Musculoskeletal
Exhibition Hall
Monday 8:15 - 9:15
(no CME credit)
Weekday Course

ISMRM-SMRT Joint Forum: Chasing Speed & Spatial Resolution: At What Point Is Enough?

Organizers: Claire Mulcahy, Douglas Noll
Room 710A
Monday 8:15 - 10:15
Moderators: Sheryl Foster & Stefan Skare
8:15
Physicist's Perspective: Reduction of Imaging for Value in MRI
James Pipe1

1Mayo Clinic, United States

MRI technology is extremely powerful but relatively expensive, somewhat unreliable, complex to operate, and (thus) often poorly utilized.  While most institutions attempt to optimize MRI for specific use cases, the variations in “optimal” protocols across institutions (and radiologists) reflect a lack of objective criteria for diagnosis.  Arguably, even the standardization of exam slot times reflects institutions’ need for efficient scheduling, rather than optimal allocation of resources to individual patient care.  This all presents great opportunity for increasing the impact of MRI on patient care while simultaneously reducing the cost of healthcare with more efficient, targeted, accurate and actionable diagnostic scans.

8:45
Radiologist's Perspective: Reduction of Imaging for Value in MRI
Scott Reeder

9:15
Radiographer's Perspective: Reduction of Imaging for Value in MRI
Emma Hornsey1

1Austin Health, Australia

MRI is of high diagnostic value but it is historically slow and expensive.  Reducing imaging can diminish these obstacles and create value through access.   Advances in technology and working smarter with existing resources can significantly reduce examination times.  Improved access to imaging and better patient tolerance of examinations will see MRI become a front line imaging modality.   As more patients benefit from quicker diagnosis, timely treatment and better outcomes the clinical demand for MRI will only continue to grow.  The ongoing challenges within this field will be maintaining adequate levels of patient care and Radiographer job satisfaction

9:45
Neurosurgeon's Perspective: Reduction of Imaging for Value in MR
Alexander Weil1

1Sainte Justine University Hospital, Montreal, QC, Canada

10:15
Adjournment


Power Pitch

Pitch: Lung Power

Power Pitch Theater A - Exhibition Hall
Monday
Pitches: 8:15 - 9:15
Posters: 9:15 - 10:15
Moderators: Kevin Johnson & John Nouls
(no CME credit)
1
Pitch: 8:15
Poster: 9:15
Plasma 1
FEV1/FVC Mapping with Dynamic MRI - A New Regional Lung Function Test
Andreas Voskrebenzev1,2, Agilo Kern1,2, Lea Behrendt1,2, Filip Klimes1,2, Marcel Gutberlet1,2, Gesa Pöhler1,2, Frank Wacker1,2, and Jens Vogel-Claussen1,2

1Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany, 2Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany

Pulmonary function parameters like the ratio of expiratory volume in one second (FEV1) and forced vital capacity (FVC) are the current gold standard for disease diagnosis and monitoring. However, early disease detection remains limited due to missing regional information. In this study the forced expiratory maneuver was captured with a dynamic MRI acquisition, as used in Fourier decomposition or phase-resolved functional lung imaging (PREFUL), for FEV1/FVC mapping. Results were compared with spirometry, PREFUL and hyperpolarized MRI in four healthy subjects and one patient with cystic fibrosis and suggest a potentially increased sensitivity in comparison with the tidal breathing approach.

2
Pitch: 8:15
Poster: 9:15
Plasma 2
3D Magnetic Resonance Spirometry
Tanguy Boucneau1,2,3, Brice Fernandez4, Peder Larson5, Luc Darrasse1,2,3, and Xavier Maître1,2,3

1IR4M, CNRS, Orsay, France, 2IR4M, Univ. Paris-Sud, Orsay, France, 3IR4M, Université Paris-Saclay, Orsay, France, 4Applications & Workflow, GE Healthcare, Buc, France, 5Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States

Spirometry is a routine tool in pulmonology to challenge lung function. It is sensitive and specific to several common lung diseases. Nevertheless, spirometry provides a global measurement at the mouth that only characterizes the pulmonary response as a whole, and cannot specifically address regional affections. We developed a 3D MRI-based technique to non-invasively perform local spirometry throughout the lung. The final outcome is a 3D map with voxel-wise flow-volume loops over the organ. The potential of this technique is demonstrated by its sensitivity to normal, thoracic, and diaphragmatic breathings and its related regional specificity in a healthy subject.

3
Pitch: 8:15
Poster: 9:15
Plasma 3
Improved lung imaging and oxygen enhancement at 0.55T
Ipshita Bhattacharya1, Rajiv Ramasawmy1, Delaney R McGuirt1, Christine Mancini1, Robert J Lederman1, Joel Moss1, Marcus Y Chen1, Robert S Balaban1, and Adrienne E Campbell-Washburn1

1National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States

Signal dephasing at high field and low proton density, has limited the use of MRI for lung imaging. We revisit the problem, using a low field (0.55T) scanner which, due to low magnetic susceptibility, improves the signal at air-tissue boundaries like lung. Moreover, because oxygen has increased r1 relaxativity at low field, oxygen inhalation can be used to significantly increase lung signal at 0.55T. Combined, these advantages makes lung MRI lucrative at low field. In this abstract we demonstrate oxygen-enhanced lung MRI at 0.55T in healthy volunteers and Lymphangioleiomyomatosis (LAM)  patients.  

4
Pitch: 8:15
Poster: 9:15
Plasma 4
Using 129Xenon MR Imaging and Spectroscopic Signatures to Differentiate Pulmonary Arterial Hypertension from Other Cardiopulmonary Diseases
Elianna Ada Bier1,2, Ziyi Wang1,2, Aparna Swaminathan3, John Nouls2, Mu He2,4, Joseph Mammarappallil5, Sheng Lou6, Sudarshan Rajagopal7, and Bastiaan Driehuys1,2,5

1Biomedical Engineering, Duke University, Durham, NC, United States, 2Center for In Vivo Microscopy, Duke University, Durham, NC, United States, 3Department of Medicine, Duke University Medical Center, Durham, NC, United States, 4Electrical and Computer Engineering, Duke University, Durham, NC, United States, 5Radiology, Duke University Medical Center, Durham, NC, United States, 6Biostatistics & Bioinformatics, Duke University Medical Center, Durham, NC, United States, 7Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC, United States

This work sought to identify a non-invasive means to detect pulmonary arterial hypertension (PAH). 129Xenon MRI and dynamic spectroscopy were acquired in healthy volunteers and subjects with chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), left heart failure (LHF), and PAH. COPD was differentiated from PAH by increased ventilation and barrier defects, while IPF was differentiated by increased barrier uptake. PAH and LHF subjects had similar imaging features but could be differentiated by their RBC signal oscillation amplitudes. 129Xe MR imaging and spectroscopy appears capable of differentiating PAH from COPD, IPF, and LHF. 

5
Pitch: 8:15
Poster: 9:15
Plasma 5
Hyperpolarised xenon-129 MR spectroscopy and diffusion-weighted xenon-129 MRI at baseline in patients with interstitial lung disease
James A Eaden1,2, Paul JC Hughes1, Ho-Fung Chan1, Oliver Rodgers1, Guilhem J Collier1, Graham Norquay1, Matthew Austin1, Laurie J Smith1, Jim Lithgow1, Nicholas D Weatherley1, Helen Marshall1, Andrew J Swift1,2, Stephen A Renshaw1,2, Colm T Leonard3,4, Sarah Skeoch3, Nazia Chaudhuri3,4, Geoff JM Parker5, Stephen M Bianchi2, and Jim M Wild1

1The University of Sheffield, Sheffield, United Kingdom, 2Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom, 3The University of Manchester, Manchester, United Kingdom, 4The University of Manchester NHS Foundation Trust, Manchester, United Kingdom, 5Bioxydyn Ltd, Manchester, United Kingdom

Preliminary findings are presented from a prospective, longitudinal, multicentre MRI biomarker study of patients presenting with interstitial lung disease (ILD) including drug induced ILD, hypersensitivity pneumonitis, idiopathic pulmonary fibrosis and connective tissue disease ILD. At the time of writing, 27 patients have undergone baseline hyperpolarised xenon-129 (129Xe) MR spectroscopy (MRS) and 129Xe diffusion-weighted MRI. Our findings suggest significant differences in mean 129Xe apparent diffusion coefficient between the ILD subtypes at baseline but no significant differences in the red blood cell / tissue plasma ratio from dissolved 129Xe MRS. We also demonstrate correlation between pulmonary function tests and 129Xe MRI measures.

6
Pitch: 8:15
Poster: 9:15
Plasma 6
Comparison of Phase-Resolved Functional Lung (PREFUL) MRI and Hyperpolarized 129Xe MRI in Pediatric Cystic Fibrosis
Marcus J. Couch1,2, Jonathan H. Rayment3, Robert Grimm4, Andreas Voskrebenzev5,6, Jens Vogel-Claussen5,6, Felix Ratjen1,7, and Giles Santyr1,2

1Translational Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada, 2Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada, 3Division of Respiratory Medicine, British Columbia Children’s Hospital, Vancouver, BC, Canada, 4MR Application Predevelopment, Siemens Healthcare, Erlangen, Germany, 5Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany, 6Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany, 7Division of Respiratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada

Hyperpolarized 129Xe MRI provides robust measurements of ventilatory function through the measurement of the ventilation defect percent (VDP). Recent progress in 1H-based free-breathing techniques (phase-resolved functional lung; PREFUL) allows for the calculation of fractional ventilation maps, which can be similarly processed to calculate VDP. While hyperpolarized 129Xe is an established research technique, PREFUL MRI is simple to implement on any MRI scanner and therefore has good potential for use in future clinical trials in cystic fibrosis (CF). In this study, VDP measurements performed using hyperpolarized 129Xe and PREFUL MRI were compared and correlated with pulmonary function tests in pediatric CF.

7
Pitch: 8:15
Poster: 9:15
Plasma 7
Differences Between 3He and 129Xe Ventilation Heterogeneity Explained Using Oscillometry
Rachel L Eddy1,2, Andrew Westcott1,2, Geoffrey N Maksym3, David G McCormack4, and Grace Parraga1,2,3,4

1Robarts Research Institute, London, ON, Canada, 2Department of Medical Biophysics, Western University, London, ON, Canada, 3School of Biomedical Engineering, Dalhousie University, Halifax, NS, Canada, 4Division of Respirology, Department of Medicine, Western University, London, ON, Canada

129Xe MRI ventilation defects were previously shown to be greater and more numerous than 3He MRI ventilation defects in patients with chronic obstructive pulmonary disease (COPD) and asthma, however the underlying biomechanical explanation for these differences has not been determined. Here we evaluated the relationships of 3He and 129Xe MRI ventilation defect percent (VDP) with oscillometry measurements acquired in patients to better understand the lung biomechanical constraints that lead to such differences. 129Xe VDP was significantly related to total respiratory-system resistance whereas 3He was not which may suggest increased sensitivity of 129Xe to resistance throughout the entire airway tree.

8
Pitch: 8:15
Poster: 9:15
Plasma 8
Improved Pulmonary 129Xe Ventilation Imaging via 3D-Spiral UTE MRI
Matthew M. Willmering1, Peter J. Niedbalski1, Hui Wang1,2,3, Laura L. Walkup1, Ryan K. Robison4, James G. Pipe5, Zackary I. Cleveland1,3,6, and Jason C. Woods1,3,6

1Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States, 2Philips, Cincinnati, OH, United States, 3University of Cincinnati, Cincinnati, OH, United States, 4Phoenix Children’s Hospital, Phoenix, AZ, United States, 5Mayo Clinic, Rochester, MN, United States, 6University of Cincinnati Medical Center, Cincinnati, OH, United States

Functional lung imaging via inhaled hyperpolarized 129Xe MRI has been shown to provide sensitive regional maps of ventilation and gas-exchange. Traditionally, ventilation images are acquired via standard Cartesian or less commonly radial sequences. Previously reported results have shown promise for 2D-spiral sequences with increased SNR and/or shorter acquisition lengths. In this study, a 3D-spiral sequence (FLORET) was implemented and compared to Cartesian, radial, and 2D-spiral acquisition techniques. This is the first implementation and comparison of a 3D-spiral UTE technique to acquire hyperpolarized gas images.

9
Pitch: 8:15
Poster: 9:15
Plasma 9
The Accuracy of Hyperpolarized 129Xe Ventilation Derived from 3D Radial Gas Exchange MRI versus Multi-Slice Gradient Echo Imaging
Mu He1,2, Ziyi Wang2,3, Leith Rankine2,4, Elianna A Bier2,3, John Nouls2, and Bastiaan Driehuys2,4

1Department of Electrical Engineering and Computer, Duke University, DURHAM, NC, United States, 2Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 3Department of Biomedical Engineering, Duke University, DURHAM, NC, United States, 4Department of Medical Physics, Duke University, DURHAM, NC, United States

Both multi-slice GRE and 3D-radial acquisitions can image regional ventilation in the lungs. Here, we sought to evaluate the accuracy of the ventilation images acquired as part of a 3D-radial gas-exchange acquisition by comparing them with those acquired with a standard GRE acquisition. Linear-binning quantification was applied on both acquisitions to derive the quantitative metrics, through which we found good qualitative and modest pixel-wise agreement between the two ventilation scans. With further reconciliation of bias-field correction and threshold-setting for the 3D-radial pipeline, it could become a one-stop shop for single-breath ventilation and gas exchange imaging.

10
Pitch: 8:15
Poster: 9:15
Plasma 10
MR radiomics analysis in predicting the pathological classification and TNM staging of thymic epithelial tumors
Gang Xiao1, Wei-Cheng Rong1, Zhong-Qiang Shi2, Xiao-Cheng Wei3, Wen Wang1, Yu-Chuan Hu1, and Guang-Bin Cui1

1Tangdu Hospital, Xi’an, China, 2GE Healthcare, Shanghai, China, 3GE Healthcare, Beijing, China

To explore the performance of MR radiomics in predicting the pathological classification and staging of thymic epithelial tumors (TETs), we built two radiomics models based on support vector machine. Besides, we developed a radiomics nomogram for predicting risk stratification of advanced TETs. The models achieved an area under the curve of 77.1% or 90.8% in the test cohort in distinguishing low-, high-risk thymomas and thymic carcinomas or early and advanced TETs. The radiomics model, symptom, and pericardial effusion constituted a radiomics nomogram, with a C-index of 0.957 in the test cohort. Thus, MR radiomics can be useful for assessing TETs.

11
Pitch: 8:15
Poster: 9:15
Plasma 11
Evaluation of automatic methods for arterial input function extraction for perfusion quantification in the lung.
Marta Tibiletti1, Josephine H Naish1,2, Paul JC Hughes3, Helen Marshall3, Colm Leonard4, Sarah Skeoch4,5, Nazia Chaudhuri4,6, Ian Bruce4,7, James A Eaden3,8, Stephen Bianchi8, Jim Wild3, and Geoff JM Parker1,9

1Bioxydyn Limited, Manchester, United Kingdom, 2Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom, 3POLARIS, Academic Radiology, University of Sheffield, Sheffield, United Kingdom, 4The University of Manchester, Manchester, United Kingdom, 5Royal United Hospitals Bath NHS Foundation Trust, Bath, United Kingdom, 6The University of Manchester NHS Foundation Trust, Manchester, United Kingdom, 7Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom, 8Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom, 9Quantitative biomedical Imaging Lab, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, United Kingdom

We developed automatic methods to extract the AIF for lung first pass perfusion DCE and compared their performance with manual selection of an ROI in the pulmonary artery (PA). Dynamic enhancement was calculated by simple subtraction and with a shuffle subtraction. Early enhancing voxels with the highest enhancing values were selected. We demonstrated that the shuffle subtraction is a more robust method, since it avoids including the early enhancing subclavian vein. Our results suggest obtaining the AIF automatically from pixels within the RV may be more robust against partial volume effects and removes inter-reader variability.

12
Pitch: 8:15
Poster: 9:15
Plasma 12
3D UTE Yarn Ball Acquisition MRI for Quantification of Lung Water Content
William Quinn Meadus1, Richard Thompson1, Robert Stobbe1, and Christian Beaulieu1

1Biomedical Engineering, University of Alberta, Edmonton, AB, Canada

The goal of this study was to develop and validate a fast, robust and quantitative MRI method for the evaluation of lung water density, for the detection of pulmonary edema. Short lung T2* necessitates ultrashort TE (UTE) acquisitions. We propose a novel optimized UTE Yarn-Ball k-space trajectory that uses ~15% of the pure radial readouts arms required to achieve full sampling. Phantom studies validated accurate water density quantification. A dual-echo approach enabled automated lung tissue segmentation. An optimized Yarn-Ball k-space trajectory yields three-dimensional spin-density weighted lung water images (2.5mm isotropic resolution), without the need for breath-holding, in ~2 minutes.

13
Pitch: 8:15
Poster: 9:15
Plasma 13
Combined ventilation and perfusion imaging using dynamic susceptibility contrast 19F-MRI of inhaled perfluoropropane
Mary Neal1, Ben Pippard1, A John Simpson2, and Pete Thelwall1

1Newcastle Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom, 2Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom

19F-MRI of inhaled perfluoropropane (PFP) can be used to assess pulmonary ventilation. PFP has a short in vivo T2(~2ms) arising from magnetic field inhomogeneity in the lung, reflecting the different magnetic susceptibilities of adjacent alveolar walls and gas components. Intravenous injection of a paramagnetic contrast agent to the pulmonary circulation can transiently reduce these magnetic susceptibility gradients, raising the T2* of inhaled PFP in regions directly adjacent to well-perfused lung. We present the first in man demonstration of combined pulmonary ventilation and perfusion assessment using 19F-MRI of inhaled PFP with concurrent administration of a gadolinium-based contrast agent.

14
Pitch: 8:15
Poster: 9:15
Plasma 14
Investigating the relationship between free-breathing 1H and breath-hold 3He MRI in patients with cystic fibrosis
Helen Marshall1, Andreas Voskrebenzev2, Alberto Biancardi1, Bilal A Tahir1, Laurie Smith1,3, Jim M Wild1, and Jens Vogel-Claussen2

1POLARIS, Academic Radiology, University of Sheffield, Sheffield, United Kingdom, 2Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany, 3Sheffield Children's Hospital, Sheffield, United Kingdom

Free-breathing non-contrast enhanced 1H MRI techniques show promise as a surrogate for ventilation imaging but more validation against methods which directly image lung ventilation is needed in patients.  The aim of this work was to investigate the relationship between 1H free-breathing and 3He breath-hold ventilation images in patients with CF. Phase-resolved functional lung (PREFUL) 1H and 3He ventilation images were compared in 10 patients with CF.  Qualitative similarities were observed between techniques to varying degrees.  Ventilation defect percentage showed strong correlation between methods and with FEV1, although median and inter-quartile range fractional ventilation values were not related.

15
Pitch: 8:15
Poster: 9:15
Plasma 15
Oxygen-enhanced UTE MRI for Quantification of Dynamic Lung Function
Wei Zha1, Kevin M Johnson1,2, Robert V Cadman1, Scott K Nagle1,2,3, and Sean B Fain1,2,4

1Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, 2Radiology, University of Wisconsin-Madison, Madison, WI, United States, 3Pediatrics, University of Wisconsin-Madison, Madison, WI, United States, 4Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States

Three-dimensional dynamic imaging using free-breathing oxygen-enhanced (OE) ultrashort echo time (UTE) MRI can measure change of partial pressure of oxygen (ΔPO2) and wash-in/out time constants. Nine healthy subjects underwent the dynamic OE MRI protocol at 1.5T. A subset of 4 subjects underwent repeated exams and 2 of these 4 underwent the same protocol at 3.0T on the same day. The inter-exam variations at 1.5T suggest good quantitative measurements of lung function and wash-in/out dynamics with variations observed in ΔPO2max. The parametric maps imply comparable wash-in/out time constants and normal ventilation measured at 1.5T vs. 3.0T.


Power Pitch

Pitch: Artificial Intelligence Neuro

Power Pitch Theater B - Exhibition Hall
Monday
Pitches: 8:15 - 9:15
Posters: 9:15 - 10:15
Moderators: Christopher Filippi & CC Tchoyoson Lim
(no CME credit)
16
Pitch: 8:15
Poster: 9:15
Plasma 16
Synthetic MRI through a Deep Neural Network Based Relaxometry and Segmentation
Peng Cao1, Jing liu1, Shuyu Tang1, Andrew Leynes1, and Peder Larson1

1University of California at San Francisco, University of California at San Francisco, San Francisco, CA, United States

This study demonstrated a method for 3D synthetic MRI through a deep neural network Based Relaxometry and Segmentation. Ranges of T1 and T2 values for gray matter, white matter and cerebrospinal fluid (CSF) were used as the prior knowledge. The proposed method can directly generate brain T1 and T2 maps in conjunction with segmentation based bias field correction and synthetic MRI.  

17
Pitch: 8:15
Poster: 9:15
Plasma 17
High-resolution 3D MR Fingerprinting using parallel imaging and deep learning
Yong Chen1,2, Zhenghan Fang1,2, Dinggang Shen1,2, and Weili Lin1,2

1Radiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

In this study, a high-resolution 3D MR Fingerprinting technique, combining parallel imaging and deep learning, was developed for rapid and simultaneous quantification of T1 and T2 relaxation times. Our preliminary results show that, with the integration of parallel imaging and deep learning techniques, whole-brain quantitative T1 and T2 mapping with 1-mm isotropic resolution can be achieved in ~6 min, which is feasible for routine clinical practice.

18
Pitch: 8:15
Poster: 9:15
Plasma 18
AUTOMATED BRAIN TISSUE SEGMENTATION USING DEEP LEARNING AND IMPERFECT LABELING
Chandan Ganesh Bangalore Yogananda1, Benjamin C Wagner1, Gowtham K Murugesan1, Sahil S Nalawade1, Ananth J Madhurantakam1, and Joseph A Maldjian1

1Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States

This work presents a deep learning pipeline to perform brain tissue segmentation on T1w Magnetic Resonance images (MRI). Two separate 3D-Dense-Unets were designed: GW-net to segment the gray matter (GM) and white matter (WM) and CSF-net to segment the cerebrospinal fluid (CSF). The network was trained on T1w MRI from 785 datasets in the iTAKL study with their corresponding SPM12 segmentations as ground truth and tested on 50 held-out subjects from the iTAKL study, 50 subjects from the AADHS study and 131 subjects from the Human Connectome project (HCP). Our pipeline showed improved segmentations when tested on simulated data with known ground truth as compared to the existing neuroimaging packages including SPM12, FSL and CAT12.

19
Pitch: 8:15
Poster: 9:15
Plasma 19
MR IMAGE RECONSTRUCTION FROM UNDERSAMPLED k-SPACE USING DEEP LEARNING
Chandan Ganesh Bangalore Yogananda1, Sahil S Nalawade1, Gowtham K Murugesan1, Benjamin C Wagner1, Ananth J Madhurantakam1, and Joseph A Maldjian1

1Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States

  This work presents a deep learning approach to reconstruct MR images from undersampled k-space on 3D-FLAIR MR images. IR-net, a patch based 3D-Dense U-net, was designed to achieve this. 600 [JM1] [CGBY2] 3D-FLAIR MR images were used for training and testing. Aliased images were created by undersampling the high resolution 3D-FLAIR images in k-space using a Poisson distribution filter. The network was trained on patches from 550 aliased k-space data with their corresponding high resolution 3D-FLAIR MR images as ground truth and 50 images were held out for testing. IR-net successfully reconstructed the aliased images with significant improvement in SSIM and PSNR.  [JM1]Are these 600 image slices, or 600 3D image volumes?  [CGBY2]600 3D images.

20
Pitch: 8:15
Poster: 9:15
Plasma 20
Fully-Automated Glioma Volumetric Segmentation and Treatment Response Assessment in MRI using Deep Learning
Ken Chang1, Andrew L Beers1, Harrison Bai2, James Brown1, K Ina Ly3, Xuejun Li4, Joeky Senders5, Vasileios Kavouridis5, Alessandro Boaro5, Chang Su6, Ena Agbodza2, Wenya Linda Bi5, Otto Rapalino3, Weihua Liao4, Qin Shen7, Hao Zhou4, Bo Xiao4, Yinyan Wang8, Paul Zhang2, Marco Pinho1, Patrick Wen9, Tracy Batchelor3, Omar Arnaout5, Bruce Rosen1, Elizabeth Gerstner3, Li Yang7, Raymond Huang5, and Jayashree Kalpathy-Cramer3

1Radiology, Massachusetts General Hospital, Boston, MA, United States, 2Hospital of the University of Pennsylvania, Philadelphia, PA, United States, 3Massachusetts General Hospital, Boston, MA, United States, 4Xiangya Hospital, Changsha, China, 5Brigham and Women’s Hospital, Boston, MA, United States, 6Yale School of Medicine, New Haven, CT, United States, 7The Second Xiangya Hospital, Changsha, China, 8Beijing Tiantan Hospital, Beijing, China, 9Dana-Farber Cancer Institute, Boston, MA, United States

Longitudinal assessment of glioma burden is important for evaluating treatment response and tumor progression. Delineation of tumor regions is typically performed manually but is time-consuming and subject to inter-rater and intra-rater variability. Therefore, there has been interest in developing automated approaches to calculate 1) glioma volume and 2) the product of maximum diameters of contrast-enhancing tumor (the key measure used in the Response Assessment for Neuro-Oncology (RANO) criteria). We present a fully automated pipeline for brain extraction, tumor segmentation, and RANO measurement (AutoRANO). We show the utility of this pipeline on 713 MRI scans from 54 post-operative glioblastoma patients, demonstrating capacity for tumor burden measurement.

21
Pitch: 8:15
Poster: 9:15
Plasma 21
Automatic detection and classification of brain tumors using deep learning and based on conventional MRI and clinical information
Moran Artzi1,2,3, Moshe Yerachmiel4, Snir Shalom4, and Dafna Ben Bashat1,2,3

1Sagol Brain Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel, 2Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel, 3Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel, 4The Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel

Automatic detection and classification of brain tumors was performed using deep learning based on conventional MRI and clinical information. A total of 441 patients where included: 202 patients with high grade glioma and 239 patients with brain metastases. Classification was performed using resnet34 architecture. The input data for classification were FLAIR images, post contrast T1W images and patients’ clinical information. Classification results showed high accuracy=89%, specificity=91% and sensitivity=86%. For lesion localization the mean intersection over union (IoU) score was 0.64±0.17. Our results indicate the promising potential of a deep learning approach for automatic non-invasive diagnosis of patients with brain tumors.

22
Pitch: 8:15
Poster: 9:15
Plasma 22
Automatic segmentation and follow-up of optic pathway gliomas using deep learning and based on conventional MRI
Moran Artzi1,2,3, Sapir Gershov4, Idan Bressler1,4, Liat Ben-Sira2,5,6, Shlomi Constantini6,7, Tomer Gazit1, Tali Halag-Milo1, and Dafna Ben Bashat1,2,3

1Sagol Brain Institute, Tel Aviv Sourasky Medical Center, Tel - Aviv, Israel, 2Sackler Faculty of Medicine, Tel Aviv University, Tel - Aviv, Israel, 3Sagol School of Neuroscience, Tel Aviv University, Tel - Aviv, Israel, 4The Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, Tel - Aviv, Israel, 5Division of Radiology, Tel Aviv Sourasky Medical Center, Tel - Aviv, Israel, 6The Gilbert Israeli Neurofibromatosis Center, Tel - Aviv, Israel, 7Department of Pediatric Neurosurgery, Tel - Aviv, Israel

Optic pathway gliomas (OPG) are heterogeneous tumors with complex shape. The aim of this study was to implement a deep-learning approach for automatic segmentation and follow-up of patients with OPG based on conventional MRI. A total of 354 MRI scans from 53 patients where included. A neural-network with a U-net architecture was trained for segmentation of lesion area. The similarity coefficient score between segmentation results and ground truth was 0.812±0.159, with sensitivity=0.799±0.188, specificity=0.999±0.002 and correlation of r=0.987 (p<0.001) between lesion volumes. These results demonstrate the potential applicability of the proposed method for automatic radiological follow-up of patients with OPG.

23
Pitch: 8:15
Poster: 9:15
Plasma 23
Predictive and discriminative localization of IDH genotype in high grade gliomas using deep convolutional neural nets
Adnan Ahmad1, Srinjay Sarkar1, Apurva Shah1, Santosh Vani2, Jitender Saini3, and Madhura Ingalhalikar1

1Symbiosis Centre of Medical Image Analysis, Symbiosis International University, Pune, India, 2National Institute of Mental Health and Neurosciences, Bangalore, India, 3Department of Neuroimaging & Interventional Radiology, National Institute of Mental Health and Neurosciences, Bangalore, India

Radiomics and state-of-art convolutional neural networks (CNNs) have demonstrated their usefulness for predicting genotype in gliomas from brain MRI. However, these techniques rely on accurate tumor segmentation and do not facilitate insights into the critical discrimative features. To mitigate this, we employ a novel technique called CNNs with discriminative localization (DL-CNN) on a clinical T2 weighted MRI dataset of IDH1 mutant and wild-type tumor patients, which is not only free of tumor segmentation with high classification accuracy of 86.7% but also demonstrates that the tumoral area is discriminative in mutants while in IDH1 wildtype the peri-tumoral edema is also involved.

24
Pitch: 8:15
Poster: 9:15
Plasma 24
Deep Learning for Identification of Active Lesions in Multiple Sclerosis Without Administration of Gadolinium Based Contrast Agent
Ponnada A Narayana1, Ivan Coronado1, Sushmita Datta1, Sheeba J Sujit1, Fred D Lublin2, Jerry S Wolinsky3, and Refaat E Gabr1

1Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston, Houston, TX, United States, 2Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Neurology, University of Texas Health Science Center at Houston, Houston, TX, United States

Gadolinium based contrast agents (GBCA) are routinely administered for identifying active lesions in multiple sclerosis (MS). Because of the safety concerns with GBCA, alternative methods are highly desirable to identify active lesions without GBCA. We used Deep Learning, specifically multi-layered VGG16 network, to identify active MS lesions on the pre-contrast images. The network was trained using a large number of annotated multi-modal magnetic resonance image volumes (792) acquired as a part of phase 3 clinical. The DL results look quite promising as judged by the accuracy, sensitivity, and specificity of 0.729, 0.861, 0.598, respectively. 

25
Pitch: 8:15
Poster: 9:15
Plasma 25
Thalamic Connectome Based Machine Learning for Predicting Individual Symptoms after Mild Traumatic Brain Injury
Chia-Feng Lu1, Yu-Chieh Jill Kao2,3,4, Li-Chun Hsieh3,4,5, Sho-Jen Cheng3,5, Nai-Chi Chen3, and Cheng-Yu Chen3,4,5

1Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan, 2Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan, 3Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan, 4Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, 5Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan

Mild traumatic brain injury (mTBI) can cause persistent post-concussion symptoms in 15-20% patients, however the presented type and severity of symptoms differ largely between patients. This study recruited 53 mTBI patients and 44 healthy controls to demonstrate the feasibility in using the imaging features of thalamic connectome combined with machine-learning regression models for the individualized prediction of clinical symptoms.

26
Pitch: 8:15
Poster: 9:15
Plasma 26
A Machine Learning approach to Predict Age-Related Motor Performance using MRI-MRS data
Akila Weerasekera1, Adrian Ion-Margineanu2, Oron Levin1, Diana Sima3, Sabine Van Huffel1, Stephan Swinnen1, and Uwe Himmelreich1

1University of Leuven, leuven, Belgium, 2Philips UK, Belfast, United Kingdom, 3icometrix, leuven, Belgium

Aging is associated with gradual alterations in structural and neurochemical characteristics of the brain, which can be assessed in vivo by MRI and MRS modalities. The process of brain aging occurs in accord with a general decline in cognitive-motor performance and increases the risk of neurodegeneration. We used MRI-MRS data from 86 individuals as inputs for machine learning models5 to predict motor performance in healthy individuals. Our analysis shows that application of machine learning algorithms on combination of age, gender and MR data can accurately predict motor performance and has potential to be used as a biomarker for neuro related diseases.

27
Pitch: 8:15
Poster: 9:15
Plasma 27
A deep learning framework with redundancy removal and its diagnostic performance of Parkinson's disease
Fan Huang1, Mingyi Zhou2, Shi-ming Wang1, Jing Wu2, Liaqat Ali2, Yi-Hsin Weng3, Yao-Liang Chen4, Jiun-Jie Wang1, and Yipeng Liu2

1Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan, 2School of Information and Communication Engineering, University of Electronic Science and Technology of China, Chengdu, China, 3Neurology, Chang Gung Memorial Hospital, Taoyuan, Taiwan, 4Diagnostic Radiology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan

Computer-aided diagnosis using deep learning methods shows its potential in medical images classifications. This study aims to examine the diagnostic performance of diffusion tensor imaging using a 4-steps framework for deep learning to differentially diagnose patients with Parkinson's disease(PD) and normal controls(NC).

28
Pitch: 8:15
Poster: 9:15
Plasma 28
Hippocampal segmentation for brains with extensive atrophy using three-dimensional convolutional neural networks
Maged Goubran1, Edward Ntiri1, Hassan Akhavein1, Melissa Holmes1, Sean Nestor1, Ramirez Joel1, Sabrina Adamo1, Fuqiang Gao1, Christopher Scott1, Anne Martel1, Walter Swardfager1, Mario Masellis1, Rick Swartz1, Bradley MacIntosh1, and Sandra Black1

1Sunnybrook Research Institute, Toronto, ON, Canada

Obtaining hippocampal volumes through manual segmentation requires an expert and is time consuming. Automated segmentation techniques would benefit from user-friendly and publicly accessible to tools, and robust results in the face of brain diseases. To accomplish these objectives, we trained a 3D convolutional neural network to segment the hippocampus automatically. Our algorithm was more accurate and time efficient compared to 4 publicly available state-of-the-art methods when considering a wide range of patient groups. Thus, we present a new method for obtaining hippocampal volumes, an important biomarker in aging, disease, and dementia.

29
Pitch: 8:15
Poster: 9:15
Plasma 29
Functional MRI-based Deep Learning Classification between Temporal Lobe Epilepsy Patients and Healthy Controls
Maribel Torres-Velázquez1, Gyujoon Hwang2, Cole John Cook2, Bruce Hermann3, Jeffery R. Binder4,5, M. Elizabeth Meyerand1,2,6, and Alan B. McMillan6

1Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, 2Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States, 3Neurology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States, 4Neurology, Medical College of Wisconsin, Milwaukee, WI, United States, 5Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States, 6Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States

Common machine learning approaches to differentiate between Temporal Lobe Epilepsy (TLE) and healthy controls often include extensive preprocessing techniques that often entail feature extraction, resulting in a more time-intensive and variable approach. Utilizing data from both the Epilepsy Connectome Project (ECP) and Human Connectome Project (HCP), this study attempts to develop, train, and validate a deep learning classifier to automatically differentiate between TLE patients and healthy subjects using resting-state fMRI (rs-fMRI) and task fMRI (t-fMRI) data alone without advanced preprocessing steps or feature extraction.

30
Pitch: 8:15
Poster: 9:15
Plasma 30
Using convolutional neural networks to predict infarct development in acute ischemic stroke patients:  does reperfusion status matter?
Yuan Xie1, Yannan Yu1, Thoralf Thamm1, Charles Huang1, Enhao Gong1, Soren Christensen1, Maarten Lansberg1, and Greg Zaharchuk1

1Stanford University, Stanford, CA, United States

Convolutional Neural Network has shown promising results in stroke treatment outcome predictions. Our study explores the hypothesis of whether training a CNN model with patients who have similar treatment outcomes can improve the model prediction of day 5 stroke lesion.


Power Pitch

Pitch: Pediatric - Ain't Misbehaving on Purpose

Power Pitch Theater C - Exhibition Hall
Monday
Pitches: 8:15 - 9:15
Posters: 9:15 - 10:15
Moderators: Andrea Gropman
(no CME credit)
31
Pitch: 8:15
Poster: 9:15
Plasma 31
Increased brain perfusion in neonatal hypoxic ischemic injury with negative reading of DWI, T1/T2-weighted images: Implications of perfusion MRI for reperfusion response monitoring and prognostication
Qiang Zheng1,2, Minhui Ouyang1, Juan Sebastian Martin-Saavedra1, Sandra Saade-Lemus1, Qinlin Yu1, Raymond Wang Sze1, John Flibotte1,3, John Detre3, Hao Huang1,3, and Misun Hwang1,3

1Children's Hospital of Philadelphia, Philadelphia, PA, United States, 2Yantai University, Yantai, China, 3University of Pennsylvania, Philadelphia, PA, United States

Brain perfusion plays an important role in the diagnosis and prognosis of neonatal hypoxic ischemic injury (HII). However, the studies on perfusion changes in HII neonates with negative reading in conventional magnetic resonance imaging (MRI) (HII-) are rarely reported. Here, we used arterial-spin-labeled perfusion MRI to compare cerebral blood flow among health controls, HII neonates with positive reading of conventional MRI images (HII+) and HII- neonates. The results demonstrate that perfusion is altered in HII neonates even with negative reading of conventional MRI images, suggesting importance of inclusion of perfusion MRI for evaluating HII in clinical practice and research. 

32
Pitch: 8:15
Poster: 9:15
Plasma 32
Music in preterm infants enhances maturation of neural pathways involved in emotion processing
Joana Sa de Almeida1, Lara Lordier2, Benjamin Zollinger3, Nicolas Kunz4, Matteo Bastiani5,6, Laura Gui7, François Lazeyras7, and Petra S. Hüppi2

1Division of Development and Growth, Department of Pediatrics, University of Geneva, Geneva, Switzerland, 2Division of Development and Growth, Department of Pediatrics, Geneva University Hospitals, Geneva, Switzerland, 3Psychology, Yale University, New Haven, CT, United States, 4Center of BioMedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, 5Wellcome Centre for Integrative Neuroimaging (WIN) - Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), University of Oxford, Oxford, United Kingdom, 6Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom, 7Center of BioMedical Imaging (CIBM), University of Geneva, Geneva, Switzerland

Prematurity disrupts brain maturation during a critical period of development and music potentially enhances cognitive-socio-emotional pathways affected by prematurity. Using multi-modal MRI, we evaluated the structural impact of a music intervention during NICU stay in preterm infants’ brains, namely in WM through DTI ROI and tractography analysis and in amygdala through volumetric analysis. Overall, WM microstructural maturity was decreased in preterm control vs full-term newborns. In comparison to preterm control, preterm exposed to music demonstrate improved WM maturation in uncinate fasciculus, external capsule/claustrum/extreme capsule and larger amygdala volumes, proving a structural effect of music intervention on emotional processing neural pathways.

33
Pitch: 8:15
Poster: 9:15
Plasma 33
Early Language and Motor Functional Network Connectivity from Infancy to Early Childhood
Muriel Bruchhage1,2, Giang Chau Ngo1,2, Sean C. L. Deoni1,2,3, and Viren A. D'Sa1,2

1Warren Alpert School of Medicine, Brown University, Providence, RI, United States, 2Women and Infants Hospital of Rhode Island, Providence, RI, United States, 3MNCHD & T, Bill & Melinda Gates Foundation, Seattle, WA, United States

While childhood is a period of rapid brain development defined by early motor and language milestones, very little is known about the development of functional networks with increasing milestone abilities. We investigated correlation patterns between resting state functional MRI network connectivity and standardized scores for motor and language milestone functions in a large cohort of typically developing children spanning from 3 months to 6 years of age. We demonstrate distinct functional network connectivity patterns for major motor and language milestone functions, which increase in number with task complexity.

34
Pitch: 8:15
Poster: 9:15
Plasma 34
Variations in tract-specific fibre density and morphology with puberty and behaviour across childhood
Sila Genc1,2, Charles B Malpas2,3, Marc L Seal1,2, and Timothy J Silk2,4

1Department of Paediatrics, University of Melbourne, Parkville, Australia, 2Developmental Imaging, Murdoch Children's Research Institute, Parkville, Australia, 3Department of Medicine, University of Melbourne, Parkville, Australia, 4School of Pschology, Deakin University, Geelong, Australia

Microstructural development is dynamic throughout childhood and adolescence. Modelling these profiles requires statistical flexibility to understand complex interplays between related phenotypes such as sex, pubertal stage, and age. We leverage the fixel-based analysis framework and compute fibre density and morphology metrics in selective white matter tracts, to enable longitudinal mixed-effects modelling of multiple phenotypes. We show that longitudinal development of white matter fibre properties in children aged 9–14 dominates in posterior fibres. Increases in fibre density are associated with increases in pubertal stage and attention dysfunction, and protracted increases in fibre density are associated with greater internalising behaviours.

35
Pitch: 8:15
Poster: 9:15
Plasma 35
Changes in functional brain connectivity associated with the development of executive functions during early childhood
Giang-Chau Ngo1,2, Muriel M. K. Bruchhage1,2, John L. Rogers1,2, Joshua Beck1,2, Viren D'Sa1,2, and Sean C.L. Deoni1,2,3

1Warren Alpert Medical School, Department of Pediatrics, Brown University, Providence, RI, United States, 2Women and Infants Hospital of Rhode Island, Providence, RI, United States, 3MNCHD&T, Bill & Melinda Gates Foundation, Seattle, WA, United States

Task-based functional MRI (fMRI) has been commonly used to study executive functions but may be difficult to implement for children younger than 5-year-old. In this work, resting sate fMRI is combined with in-house tablet-based tasks which evaluate reaction and inhibition control in children from 2 to 5 years of age. The aim is to determine differences in brain connectivity related to the children’s performance of these two tasks. Preliminary results demonstrated the importance of the language, visual and attention networks during the reaction task and asymmetrical changes in frontal parietal and sensorimotor network connectivity associated with the development of inhibition control.

36
Pitch: 8:15
Poster: 9:15
Plasma 36
Development-based Joint Parcellation of Human and Macaque Brains during Infancy
Jing Xia1,2, Fan Wang2, Zhengwang Wu2, Li Wang2, Caiming Zhang1, Weili Lin2, Dinggang Shen2, and Gang Li2

1Department of Computer Science and Technology, Shandong University, Jinan, China, 2Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

Joint cortical parcellation maps of human and macaque infant brains with corresponding regions are highly desirable, since they provide basic common cortical parcels for both region-based and network-based studies of two closely-related species. Developmental patterns of infants indicate underlying rapid changes of microstructures, which determine the molecular and functional principles of the cortex. Leveraging 210 longitudinal human infant MRI scans and 140 longitudinal macaque infant MRI scans, we develop a novel method to generate the first joint parcellation maps of human and macaque infants based on their developmental patterns.

37
Pitch: 8:15
Poster: 9:15
Plasma 37
Differences in Brain Development in a High and Low Economic Setting
Sean Deoni1,2, Giang-Chau Ngo2, Muriel Bruchhage2, and Douglas Dean3

1MNCHD&T, Bill & Melinda Gates Foundation, Seattle, WA, United States, 2Pediatrics, Brown University, Providence, RI, United States, 3University of Wisconsin at Madison, Madison, WI, United States

Adverse environmental conditions throughout infancy and childhood have potential to result in neurodevelopment delays and impaired cognitive outcomes.  Children born in low and middle income countries (LMICs) often experience significant malnutrition, inadequate sanitation, and are exposed to poor water and air quality, all of which can affect brain and cognitive development.  However, there are limited reports of brain growth in LMICs, with cognitive development often assessed indirectly through measures of physical growth (child height and weight).  Here we present the first reports of brain volume growth in children from a low resource area of India.  Relative to reference brain growth charts derived from a large cohort of healthy children in Providence RI, we find significant brain growth delay, particularly amongst girls.  These results shine new light on the importance of living conditions on child brain health.

38
Pitch: 8:15
Poster: 9:15
Plasma 38
Grey matter changes in adolescents participating in a meditation training
Justin P Yuan1, Colm G Connolly2, Eva Henje Blom3,4, Leo P Sugrue1, Tony T Yang4, Duan Xu1, and Olga Tymofiyeva1

1Department of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, 2Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States, 3Department of Clinical Science/Child- and Adolescent Psychiatry, Umeå University, Umeå, Sweden, 4Department of Psychiatry, University of California, San Francisco, San Francisco, CA, United States

Meditation is a popular mind-body practice with numerous benefits, but its neural mechanism remains unclear. Previous MRI studies have shown morphometric changes associated with meditation, such as increased grey matter volume (GMV). However, these findings were in adults and adolescents remained understudied. Using voxel-based morphometry, we assessed GMV changes in adolescents participating in a training containing elements from mindfulness meditation and yoga-based practices. We found a significant GMV decrease in the left posterior insula, a key homeostatic awareness and interoception region. The decreasing GMV opposes previous findings of structural increase in adults, which may be due to adolescence-specific developmental processes.

39
Pitch: 8:15
Poster: 9:15
Plasma 39
Cortical Thickness and White Matter Connectivity in preschool Children with Autism Spectrum Disorder
Shijun Li1, Qiansu Yang1, Denghao Li2, Weiwei Men3, Gang Liu1, Yanwei Lv4, and Lin Ma1

1PLA General Hospital, Beijing, China, 2Tsinghua University, Beijing, China, 3Center for MRI Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, 4Beijing Jishuitan Hospital, Beijing, China

Structural magnetic resonance imaging (MRI) is suitable to describe brain anatomy, and altered cortical thickness and connectivity are the keys feature of autism spectrum disorder (ASD) pathophysiology. By processing T1-weighted imaging and diffusion-tensor imaging data from same subjects, cortical thickness and white matter connectivity were shown respectively, and some differences of brain areas were found between typically developing (TD) preschool children group and ASD, which might be related to the behaviors of ASD preschool children. Compared with TD, the thickness of right middle post cingulada gyrus and sulcus increased and its close white matter's fractional anisotropy (FA) of right superior frontal area decreased (P<0.01) in ASD group. These findings may be the morphological biomarkers, which will help guide the precise intervention or treatment in preschool children with ASD as some new neural circuits.

40
Pitch: 8:15
Poster: 9:15
Plasma 40
Multimodal Stratification Biomarkers: Unravelling Electrophysiological Latency Differences in Autism Spectrum Disorder with the help of DTI and MEGAPRESS
Timothy P Roberts1, Luke Bloy1, and Jeffrey I Berman1

1Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, United States

Electrophysiological delays in sensory (e.g. auditory) evoked responses are hallmarks of ASD. However, their magnitude is heterogeneous across the autism spectrum. This study approaches latency delay from a biophysical standpoint, focusing on axonal conduction velocity and synaptic transmission speed as potential mediators of ultimate latency. Combining MEG measures of cortical response latency with MR surrogates of conduction velocity (thalamocortical white matter diffusion fractional anisotropy) and synaptic transmission (MRS estimates of the neurotransmitter GABA) allows the stratification of children with ASD into subgroups dominantly dependent on conduction velocity vs synaptic transmission respectively. Such biological stratification may offer promise for targeted intervention.

41
Pitch: 8:15
Poster: 9:15
Plasma 41
Regional and Lateralized Cortical Thickness Measurement in Children and Adolescents with Complex Congenital Heart Disease: Effects of Age, Gender, and Ciliary Dysfunction
Thomas James Lampl1, Aurelia Sahel1, Julia Wallace1, Nancy Beluk1, Vincent Lee1, Cecilia Lo2, Ashok Panigrahy1, and Rafael Ceschin3

1Department of Pediatric Radiology, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, United States, 2Developmental Biology, University of Pittsburgh, Pittsburgh, PA, United States, 3Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA, United States

Both regional and lateralized differences in cerebral cortical thickness were noted in CHD patients compared to controls during a protracted period of critical brain development during childhood and adolescent period. The regional vulnerability was localized to important known cognitive control network including the prefrontal region, salience network and the default mode network . Importantly, ciliary motion abnormalities accounted for most of these regional and lateralized differences in cortical thickness between CHD and controls, underscoring the importance of ciliary mutations/genetic abnormalities underlying cortical dysmaturation in CHD patients.

42
Pitch: 8:15
Poster: 9:15
Plasma 42
Brain Microstructural Changes Support Cognitive Deficits in Normal Children Born to HIV-infected Mothers
Santosh Kumar Yadav1, Rakesh K Gupta2, Sabah N Ahmed1, Sheema Hashem1, Ajaz A Bhat1, Ravindra K Garg3, Vimala Venkatesh4, Muhammad W Azeem5, and Mohammad Haris1,6

1Division of Translational Medicine, Sidra Medicine, Doha, Qatar, 2Department of Radiology and Imaging, Fortis Memorial Research Institute, Gurgaon, India, 3Department of Neurology, King George Medical University, Lucknow, India, 4Department of Microbiology, King George Medical University, Lucknow, India, 5Department of Psychiatry, Sidra Medicine, Doha, Qatar, 6Laboratory Animal Research Center, Qatar University, Doha, Qatar

In the current study, we evaluated the brain integrity [by mapping the fractional anisotropy (FA) and mean diffusivity (MD)] and neurocognitive performance (NP) in normal children (NCI) born to HIV-infected mother compared to normal children (NCH) born to healthy mother and HIV-infected children (HI). Reduced FA in multiple brain sites of HI and NCI children suggests loss of tissue integrity while altered MD indicates presence of cerebral edema. Presence of tissue changes and abnormal cognition in absence of HIV-infection in NCI children advice that ART may have detrimental effects on brain.

43
Pitch: 8:15
Poster: 9:15
Plasma 43
Anomalous relationship between sensorimotor GABA levels and cortical excitability in children with Attention-deficit/hyperactivity disorder
Ashley D Harris1,2,3, David A Huddleston4, Paul S Horn4, Kim M Cecil5, Richard AE Edden6,7, Donald L Gilbert4, Stewart H Mostofsky8,9,10, and Nicolaas AJ Puts6,7

1Radiology, University of Calgary, Calgary, AB, Canada, 2Child and Adolescent Imaging Research Program, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada, 3Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada, 4Division of Pediatric Neurology, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, United States, 5Department of Radiology, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, United States, 6Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, United States, 7F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States, 8Center forNeurocognitive and Imaging Research, Kennedy Krieger Institute, Baltimore, MD, United States, 9Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, United States, 10Department of Behavioral Science and Psychiatry, Johns Hopkins School of Medicine, Baltimore, MD, United States

Reduced inhibition as shown though GABA-edited MRS and TMS measures have been suggested to underlie some of the symptomology of ADHD. In this study we apply GABA-MRS and single- and paired-pulse TMS in ADHD and typically developing cohorts to better understand altered inhibition in ADHD. We show that SICI approaches 1 with increasing GABA across both groups. Secondly, we show a convergence in SICI and single-pulse TMS responses with increasing GABA. Last, we show different factors modulate the TMS responses between ADHD and control suggesting there are additional differences in GABAergic inhibition between these two groups.

44
Pitch: 8:15
Poster: 9:15
Plasma 44
The Relation Between Nasal Nitric Oxide and Neurocognitive Outcome is Mediated by Regional Cerebral Blood Flow in Healthy Adolescents and Adolescents with Congenital Heart Disease
Vincent Jerome Schmithorst1, Ashok Panigrahy1, Philip Adams2, and Cecilia Lo2

1Radiology, UPMC Pittsburgh Children's Hospital, Pittsburgh, PA, United States, 2UPMC Pittsburgh Children's Hospital, Pittsburgh, PA, United States

Nasal nitric oxide (nNO) may be a proxy for NO or NO synthase (NOS) availability in the brain, while NO/NOS availability is likely related to metabolism and downstream to neurocognitive function.  We tested this hypothesis using a mediation analysis with nNO the independent variable, regional CBF (rCBF) as measured by ASL the mediator, and neurocognitive outcome (NIH Toolbox) the dependent variable in a cohort of normal adolescents and adolescents with congenital heart disease.  Anterior and posterior default mode network regions positively mediated all NIH Toolbox composite scores, especially crystallized cognition.  Results indicate nNO may be a powerful biomarker for brain function and metabolism.

45
Pitch: 8:15
Poster: 9:15
Plasma 45
Investigating the effects of an early intervention in preterm newborns: A resting-state functional connectivity study
Serafeim Loukas1,2, Djalel E Meskaldji1,3, Lara Lordier1, Joana Sa de Almeida1, Dimitri Van De Ville2, and Petra S Huppi1

1Division of Development and Growth, Department of Pediatrics, University of Geneva, Geneva, Switzerland, 2Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland, 3Institute of Mathematics, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland

In this study we explore the effects of an early intervention on functional connectivity in preterm newborns. A group of preterm newborns underwent musical intervention in NICU during hospitalization. At TEA, two resting-state fMRI runs were collected. The first was before and the second after the presentation of the same musical stimulus used for the early intervention. We construct the functional connectomes using Accordance and we employ connectome-based statistical methods to unveil changes in functional connectivity evoked by this familiar musical stimulus. Increased connectivity is observed in key brain areas involved in music and emotion processing supporting previous findings.


Combined Educational & Scientific Session

MRS to CEST & What Is In-Between

Organizers: Lucio Frydman, Elena Vinogradov
Room 510A-D
Monday 8:15 - 10:15
Moderators: Gopal Varma & Christoph Juchem
8:15
MRS in Tissue: What Are We Measuring?
Anke Henning1

1MPI for Biological Cybernetics, Germany

47
8:35
Dynamic Deuterium MRS Imaging for Studying Rat Heart Energy Metabolism in vivo – Initial Experience
Huan Li1,2, Xiao-Hong Zhu1, Wei Zhu1, Byeong-Yeul Lee1, Hannes Michel Wiesner1, Yi Zhang1, Tao Wang1, and Wei Chen1

1Center for Magnetic Resonance Research,Department of Radiology, University of Minnesota, Minneapolis, MN, United States, Minneapolis, MN, United States, 2Department of Radiology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, China

Assessment of myocardial energy metabolism is crucial for understanding heart function and viable myocardium after myocardial infarction. Based on our recently developed in vivo Deuterium (2H) MR spectroscopic (DMRS) approach, we further exploited the DMRS and imaging (DMRSI) methods for dynamic measurement of the myocardial energy metabolism in rat heart at 16.4 T. This work demonstrates the feasibility of in vivo DMRS for assessing myocardial energy metabolisms, and its potential to directly image the viable myocardium in hearts under conditions such as myocardial infarction.

46
8:47
Novel methods to record MR spectra in human brain without suppressing or exciting the water signal to investigate exchange-sensitive protons.
Martyna Dziadosz1, Wolfgang Bogner2, André Döring1, and Roland Kreis1

1Departments of Radiology and Biomedical Research, University Bern, Bern, Switzerland, 2Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, High-field MR Center, Vienna, Austria

Non-water-suppressed MR spectroscopy in the form of metabolite-cycled MRS and longitudinal-relaxation-enhanced MRS (also termed non-water-excitation, NWE) has come into focus when studying compounds with exchanging protons (observed in the downfield region) or compounds like NAD+ that seem to be affected by cross relaxation from water. Here, we strive to implement new NWE techniques that can be used at 3T and allow for very short TE and observation of fast exchanging protons.  2D I-CSE, a combination of 2D ISIS and slice-selection with chemical shift selective excitation, fulfills this profile and first human brain applications show large signal contributions from exchanging protons. 

8:59
CEST in Tissue: What Are We Measuring?
Daniel Gochberg1

1Vanderbilt University Medical Center, United States

In CEST, specificity is the key issue.

48
9:19
High-resolution phosphocreatine mapping of human skeletal muscle by artificial neural network-based chemical exchange saturation transfer MRI at 3T
Lin Chen1,2, Michael Schär2,3, Kannie W.Y. Chan1,2,4, Jianpan Huang4, Zhiliang Wei1,2, Hanzhang Lu1,2, Qin Qin1,2, Robert G. Weiss2,3, Peter C.M. van Zijl1,2, and Jiadi Xu1,2

1F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States, 2Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, 3Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, 4Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China

The creatine kinase reaction provides energy for cells by reversibly regenerating adenosine triphosphate from a phosphocreatine pool. Functional impairment of this system is observed in many neurodegenerative and muscle diseases. In this study, we developed a high-resolution phosphocreatine (PCr) mapping approach that can be used on standard magnetic resonance clinical scanners by specifically detecting PCr via the water proton signal using a chemical exchange saturation transfer (CEST) method. An artificial neural network was employed to achieve absolute quantification of PCr concentration. Such a mapping method offers a non-invasive, rapid imaging tool to quantify abnormalities in PCr content and distribution in musculoskeletal diseases.

49
9:31
Translating pH-sensitive PROgressive saturation for Quantifying Exchange using Saturation Times (PRO-QUEST) MRI to a 3T Clinical Scanner
Mina Kim1, Marco Battiston2, Eleni Demetriou1, Aaron Kujawa1, Torben Schneider3, Vincent Evans4, Sachi Okuchi1, David Atkinson4, Claudia Wheeler-Kingshott2,5,6, and Xavier Golay1

1Department of Brain Repair and Rehabilitation, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom, 2Queen Square MS Centre, Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom, 3Philips Healthcare, Surrey, United Kingdom, 4UCL Centre for Medical Imaging, University College London, London, United Kingdom, 5Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy, 6Brain MRI 3T Research Centre, IRCCS Mondino Foundation, Pavia, Italy

In this work, a recently developed method called PRO-QUEST (PROgressive saturation for Quantifying Exchange using Saturation Times) is translated to a 3T clinical scanner for assessing pH-sensitive indices in phantoms and a healthy volunteer. Our results demonstrate that quantification of pH sensitive indices using PRO-QUEST is feasible at 3T within clinically acceptable acquisition times. Our initial findings suggest that PRO-QUEST has the potential to provide a new biomarker to study neurological disorders associated with brain tissue acidosis.

9:43
CEST & MRS: Biochemistry (Breast Cancer)
Kristine Glunde1

1Johns Hopkins University SOM, United States

CEST & MRS: Biochemistry (Breast Cancer)

50
10:03
Self-adapting Multi-peak Water-fat Separation for Removing Lipid Artifacts in Breast Chemical Exchange Saturation Transfer (CEST) Imaging
Yu Zhao1 and Jianqi Li1

1Shanghai Key Laboratory of Magnetic Resonance, Shanghai, China

Chemical exchange saturation transfer (CEST) MRI show potential for breast lesion characterization. However, artifacts caused by strong lipid signals hinder its widespread application. To remove the artifacts, water-fat separation based on multipoint Dixon acquisition is used to obtain water-only images. Considering that RF pulses with various frequency offset in CEST preparation saturate each fat peak at different level, relative amplitudes of fat peaks are updated for building fat signal model by the numerical simulation. Based on this self-adapting multi-peak model (SMPM), a method combining nonlinear least-squares fitting and R2 *-IDEAL is used to perform the water-fat reconstruction. Phantom and in vivo breast experiments demonstrate that the proposed method successfully removes lipid artifacts.

10:15
Adjournment


Combined Educational & Scientific Session

Multimodal fMRI: From Animal to Human

Organizers: Benedikt Poser, Susan Francis, Richard Buxton, Hanzhang Lu
Room 710B
Monday 8:15 - 10:15
Moderators: Xin Yu & Richard Buxton
8:15
Multi-Modal Imaging: From Animal Models to Human
Catie Chang1

1Vanderbilt University, United States

Integrating fMRI with complementary neurophysiological measurements can provide a more comprehensive understanding of brain function, and help to clarify the neural basis of BOLD fMRI signals. Here, we will discuss multi-modal imaging studies of the human brain using simultaneous EEG-fMRI, along with studies in animal models, which allow for more direct, invasive monitoring and manipulation of neural circuits. This talk will also briefly discuss technical challenges and methodology involved in acquiring and analyzing simultaneous fMRI-electrophysiological data.

51
8:45
Optogenetic fMRI reveals ventral hippocampal modulatory effects on large-scale visual processing
Eddie C. Wong1,2, Alex L. T. Leong1,2, Celia M. Dong1,2, Anthea To1,2, and Ed X. Wu1,2

1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, China, 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China

Hippocampus has been traditionally associated to learning, memory, navigation and emotional behaviors. However, little is known regarding whether and how it influences the processing of large-scale visual sensory information. In this study, we combined optogenetic stimulation and visual fMRI to investigate the influence of the ventral hippocampus on visual processing across the central visual pathway, including superior colliculus, lateral geniculate nucleus and visual cortex. Our optogenetic fMRI results reveal for the first time the differential influences of high and low frequency ventral hippocampal activities on visual processing along the central visual pathway.

52
8:57
Neurovascular coupling in task and resting state using simultaneous calcium fiber photometry and fMRI in rats
Chuanjun Tong1, Jiankun Dai2, Yanqiu Feng1, and Zhifeng Liang2

1Institution of Medical Information, Sourthern Medical University, Guangzhou, China, 2Institution of Neuroscience, Shanghai, China

Neurovascular coupling is the foundation of functional brain imaging. We developed a dual site, dual color simultaneous GCaMP6-based fiber photometry and fMRI recording system in rats, to simultaneously record calcium and BOLD signals. Our results revealed the strong couplings in the task condition, and much weaker but still significant coupling in the resting state. We also showed that in the resting state such coupling was susceptible to different preprocessing steps. Our results provided a novel perspective on neurovascular coupling in task and resting state conditions.

53
9:09
LFP-triggered Co-activation Patterns Show That the Relationship between LFP and BOLD Is Driven by a Few Distinct Events
Xiaodi Zhang1, Wen-Ju Pan1, and Shella Keilholz1

1Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States

To gather electrophysiological evidence of time-varying functional networks, we developed a new method to analyze simultaneous fMRI and LFP data, which averages the fMRI frames at LFP power higher or lower than a threshold. The results not only show that the correlation between LFP power and BOLD is driven by a few distinct instead of a continuous interaction, but also suggests that the non-stationary resting state networks found in fMRI studies represent the time-varying behavior of LFPs.

9:21
Multi-modal Imaging in Epilepsy Research
Steven Stufflebeam1

1MGH Martinos, United States

54
9:51
Exploration of the spatial and temporal characteristics of sensorimotor neural activity in the preterm human brain with simultaneous EEG-fMRI
Tanya Poppe1, Kimberly Whitehead2, Sofia Dall'Orso3, Camilla O'Keefe1, Jakki Brandon1, Katy Vecchiato1, Rui Pedro A G Teixeira1, Felipe Godinez1, Anthony N Price1, A David Edwards1, Lorenzo Fabrizi1, and Tomoki Arichi1,3

1Centre for the Developing Brain, Kings College London, London, United Kingdom, 2Department of Neuroscience Physiology and Pharmacology, University College London, London, United Kingdom, 3Department of Bioengineering, Imperial College London, London, United Kingdom

In the developing animal brain, different patterns of neural activity have distinct roles in the establishment of brain networks at different scales. Although studies suggest that the human preterm period is a crucial time for establishing brain connectivity, the role of different frequencies of neural activity has not been studied. We therefore used simultaneous EEG-fMRI and a robotic somatosensory stimulus to study the temporal and spatial characteristics of evoked neural activity in a group of preterm infants. Specific types of neural activity were associated with different BOLD responses, suggesting that these methods offer new insights into developing brain activity.

55
10:03
Identifying focal thalamic activity underlying sleep and wake states through EEG-fMRI at 7 Tesla
Laura Lewis1,2, Giorgio Bonmassar3, Kawin Setsompop3, Robert Stickgold4, Bruce Rosen3, and Jonathan Polimeni3

1Boston University, Boston, MA, United States, 2Massachusetts General Hospital, Boston, MA, United States, 3Massachusetts General Hospital/Harvard Medical School, Boston, MA, United States, 4BIDMC/Harvard Medical School, Boston, MA, United States

The thalamus plays an important role in regulating brain states, but remains poorly understood due to the technical challenges in imaging small brain structures with simultaneous electrophysiology. We implemented simultaneous fast fMRI and EEG at 7 Tesla to achieve high-SNR imaging of thalamic dynamics during human sleep. We found that we could detect selective activity within a focal set of thalamic nuclei that preceded the moment of awakening. These results identify potential network mechanisms engaged in regulating brain states, and demonstrate the potential for multimodal 7T imaging to identify new roles for deep brain structures in regulating cortical function and cognition.

10:15
Adjournment


Oral

Microstructure: Approaching Cellular Complexity

Room 511BCEF
Monday 8:15 - 10:15
Moderators: Valerij Kiselev & Chantal Tax
56
8:15
Estimating compartment- and cell-specific microscopic anisotropy in the human brain using double-diffusion encoding spectroscopy at 7T
Chloé Najac1, Henrik Lundell2, Marjolein Bulk1, Hermien E. Kan1, Andrew G. Webb1, and Itamar Ronen1

1Radiology, C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden, Netherlands, 2Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark

Double diffusion encoding spectroscopy (DDES) offers the unique ability to estimate compartment and cell-specific micro-anisotropy (μFA) in vivo. Recently, this method allowed the estimation of intracellular micro-anisotropy in the white matter. Here, we propose to measure the μFA in different diffusion weighting settings to explore intra- and extracellular μFA in both white (WM) and grey matter (GM). We show that intracellular μFA is similar in both WM and GM, but extracellular space in WM is significantly more anisotropic compared to GM.

57
8:27
MRS Extended by Oscillating Diffusion Gradients as a Probe for Investigation of Human Brain Tissue Microstructure
André Döring1 and Roland Kreis1

1Depts. Radiology and Biomedical Research, Bern, Switzerland

Pulsed diffusion and oscillating diffusion gradients implemented in a semi-Laser sequence for measuring at long and short diffusion times were tested in a phantom and applied in vivo. Metabolite diffusion constants measured in human gray matter in 6 healthy volunteers at short diffusion times were significantly higher than those determined at long diffusion times, suggesting an enhanced sensitivity to diffusion on the cellular and subcellular level.

58
8:39
Oscillating-gradient diffusion-weighted MRI provides accurate cell radii in tumor spheroids
Marcel Kettelmann1, Stephan Niland2, Mirjam Gerwing1, Markus Wick3, Sascha Koehler3, Lydia Wachsmuth1, Moritz Wildgruber1, Johannes A Eble2, and Cornelius Faber1

1Translational Research Imaging Center (TRIC), University Hospital Muenster, Muenster, Germany, 2Institute of Physiological Chemistry and Pathobiochemistry, University Hospital Muenster, Muenster, Germany, 3Bruker BioSpin, Ettlingen, Germany

Diffusion weighted MRI using oscillating gradients has previously been shown to provide microstructural information on celllularity in tumors, which may serve as marker for monitoring therapy response. Which geometrical model for analysis of such data provides most reliable results, is, however, a matter of debate. Here, we used the IMPULSED approach, and show that cell radii in tumor spheroids of three different cell lines can be determined with high accuracy. In an in vivo model, however, deviations from radii determined by laser scanning microscopy were found.

59
8:51
In-vivo Neural Soma Imaging Using B-tensor Encoding and Deep Learning
Noemi G. Gyori1,2, Christopher A. Clark2, Iulius Dragonu3, Daniel C. Alexander1, and Enrico Kaden1

1Centre for Medical Image Computing, University College London, London, United Kingdom, 2Great Ormond Street Institute of Child Health, University College London, London, United Kingdom, 3Siemens Healthcare Ltd, Frimley, United Kingdom

Diffusion MRI is successfully used to map white matter in the brain. In this work we develop a new clinically viable technique with particular focus on grey matter microstructure. To capture the heterogeneous morphology of grey matter, it is imperative to disentangle cylindrical and spherical geometries commonly attributed to neurites and neural soma. We achieve this by leveraging the latest advances in B-tensor encoding and deep learning techniques and present microstructural feature maps of neurites and neural soma in-vivo in the human brain.

60
9:03
COMPARISON OF DIFFERENT TENSOR ENCODING COMBINATIONS IN MICROSTRUCTURAL PARAMETER ESTIMATION
Maryam Afzali1, Chantal MW Tax1, Cyrano Chatziantoniou1, and Derek K Jones1,2

1Cardiff University Brain Research Imaging Center (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom, 2School of Psychology, Faculty of Health Sciences, Australian Catholic University, Melbourne, Victoria, 3065, Australia

Diffusion-weighted imaging provides information to study the brain microstructure. Several studies in the literature have shown that there is degeneracy in the estimated parameters for a commonly used microstructural model. B-tensor encoding is one of the strategies that has been proposed to solve the degeneracy. The combination of linear-spherical tensor encoding (LTE+STE) and linear-planar (LTE+PTE) have been utilized in previous works. In this paper, we compare different combinations of b-tensor encoding, (LTE+STE), linear-planar (LTE+PTE), planar-spherical (PTE+STE) and linear-planar-spherical (LTE+PTE+STE). We also compare the results of fit using a nonlinear least square algorithm and microstructure imaging of crossing (MIX) method. The results show that the combination of tensor encodings with MIX fitting algorithm leads to lower bias and higher precision in the parameter estimates than single tensor encoding.

61
9:15
Beyond the Standard Model in Spinal Cord
Jonas Lynge Olesen1,2, Noam Shemesh3, and Sune Nørhøj Jespersen1,2

1Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark, 2Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark, 3Champalimaud Neuroscience Programme, Lisbon, Portugal

A prevalent model for the diffusion signal from neural tissue is the so-called Standard model which represents axons as “sticks”, i.e., with zero radial diffusivity.  Spinal cord tissue is characterized by larger axons than the brain which was recently shown to possibly invalidate the assumption up to large diffusion times. This calls for an appropriate extension of the Standard Model. Here, results from such an endeavour with an extensive dataset from a rat spinal cord are summarized. SM parameters were reliably estimated to be unphysical indicating that the model is insufficient in spinal cord white matter.

62
9:27
Tangential and radial diffusion in human primary somatosensory and motor cortex: evidence from in-vivo line-scan acquisitions at 7T with 250–500 micron radial resolution
Mukund Balasubramanian1,2, Robert V. Mulkern1,2, Stephan E. Maier1,3,4, and Jonathan R. Polimeni1,5,6

1Harvard Medical School, Boston, MA, United States, 2Department of Radiology, Boston Children's Hospital, Boston, MA, United States, 3Department of Radiology, Brigham and Women's Hospital, Boston, MA, United States, 4Department of Radiology, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden, 5Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 6Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States

Eight healthy volunteers were scanned at 7T using a line-scan diffusion sequence with each line prescribed perpendicularly to primary somatosensory (S1) and motor (M1) cortex, and with 250–500 micron resolution along the line. We observed tangential diffusion in S1 and radial diffusion in M1, consistent with prior reports, but with the high radial resolution used here enabling us to identify the deep layers of S1—where high diffusion anisotropy was seen—as the source of the tangential diffusion, with low anisotropy in the upper layers. In M1, radial diffusion with moderate anisotropy was seen at nearly all cortical depths.

63
9:39
Multi-Dimensional Diffusion MRI of the Human Sciatic Nerve
Michael Pridmore1, Filip Szczepankiewicz2,3,4, Guillaume Gilbert5, Brian Johnson6, Carl-Fredrik Westin2, and Richard D. Dortch1,7

1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2Radiology, Harvard Medical School, Boston, MA, United States, 3Radiology, Brigham and Women's Hospital, Boston, MA, United States, 4Random Walk Imaging AB, Lund, Sweden, 5Philips Healthcare, Markham, ON, Canada, 6Philips Healthcare, Dallas, TX, United States, 7Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States

Multi-dimensional diffusion MRI is a promising new tool to assess tissue microstructure. Here, we developed a high-resolution protocol that overcomes the challenges of nerve imaging in humans (e.g., the influence of fat, short-T2s) and translated the method to the sciatic nerve in the thigh. Preliminary results showed that measures of microscopic fractional anisotropy in sciatic nerve were 1) similar to reported measures in white matter and 2) were repeatable across scans in the same subject. Additional comparisons to conventional diffusion encodings of the sciatic nerve suggest that multi-dimensional diffusion MRI may yields more specific measures of nerve microstructure. 

64
9:51
Temporal Diffusion Ratio (TDR): A Diffusion MRI technique to map the fraction and spatial distribution of large axons in the living human brain
Flavio Dell'Acqua1, Robert Dallyn1, Andrea Chiappiniello2, Ahmad Beyh1, Chantal Tax3, Derek K Jones3, and Marco Catani1

1NatBrainLab, King's College London, London, United Kingdom, 2Department of Physics and Geology, University of Perugia, Perugia, United Kingdom, 3CUBRIC, Cardiff University, Cardiff, United Kingdom

This work presents a new approach to mapping the fraction and spatial distribution of large axons (d>3μm) across white matter (WM) in the living human brain. By collecting high b-value (b=8000 s/mm2) diffusion MRI data at two diffusion times on a Connectome scanner, we were able to generate a new contrast specific to the characteristic signal decay of large axons at different diffusion times. Using this approach, we were able to identify and discriminate consistently some of the major WM pathways expected to carry the largest axons within the human brain. WM characterisation using TDR can offer important and practical clinical applications.

65
10:03
Combined Diffusion-Relaxometry MRI to Identify Dysfunction in the Human Placenta
Paddy J. Slator1, Jana Hutter2,3, Marco Palombo1, Laurence H. Jackson2,3, Eleftheria Panagiotaki1, Alison Ho4, Lucy C. Chappell4, Mary A. Rutherford3, Joseph V. Hajnal2,3, and Daniel C. Alexander1

1Centre for Medical Image Computing, University College London, London, United Kingdom, 2Biomedical Engineering, Kings College London, London, United Kingdom, 3Centre for the Developing Brain, King's College London, London, United Kingdom, 4Women's Health Department, King's College London, London, United Kingdom

We demonstrate simultaneous diffusion-relaxometry in the in-vivo human placenta. Two MRI measures widely used for characterizing the placenta, T2* relaxometry and diffusion, are combined into a single scan. We estimate the T2*-ADC spectrum, which enables study of the coupling between these complementary MR contrasts by disentangling joint effects. This gives new potential for improved characterisation of placental dysfunction compared to single contrast MRI and/or ultrasound, and hence could inform improved evaluation of pregnancy complications.


Oral

Freeze It: Managing Motion in MRI

Room 512A-H
Monday 8:15 - 10:15
Moderators: Claudia Prieto & Tobias Schaeffter
66
8:15
Wireless motion tracking with short-wave radiofrequency
Christoph Michael Schildknecht1, David Otto Brunner1, Thomas Schmid1, Jonas Reber1, Josip Marjanovic1, and Klaas P. Pruessmann1

1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

For robust and high-quality brain imaging rigid body motion correction plays an increasingly important role.

We propose a wireless motion tracking method based on short-wave RF signal transmission that does not require a direct line of sight and can penetrate tissue and plastics between detector and marker providing a unprecedented degree of freedom in marker placement and fixation. Single digit micrometer precision during an EPI sequence could be demonstrated even at high tracking bandwidth of 100 Hz with minimal latency and operating independently from the scanner.


67
8:27
Prospective motion correction using a wireless device that combines vector observations of the static magnetic field and the rate of change of the gradient fields.
Adam van Niekerk1, Ernesta Meintjes1,2, and Andre van der Kouwe3,4

1Human Biology, University of Cape Town, Cape Town, South Africa, 2Cape Universities Body Imaging Centre (CUBIC), University of Cape Town, Cape Town, South Africa, 3Athinoula A. Martinos Center, Massachusetts General Hospital, Charlestown, MA, United States, 4Radiology, Harvard Medical School, Boston, MA, United States

Using external hardware to track patient motion allows for high frequency, accurate prospective motion correction that is robust to changes in coil set-up and subject anatomy. However, this typically comes at the expense of increased hardware complexity, difficulties in marker placement and in some cases cross-calibration. To address some of these challenges, we have developed a small, battery powered marker that uses the three-dimensional gradient spatial encoding, visible through Faraday induction, for vector-based position and orientation estimates. The device enables wireless, calibration-free prospective motion correction that can be used on an ad-hoc basis in an unmodified scanner.

68
8:39
Enhanced reliability of NMR marker localization using real-time field tracking
Alexander Aranovitch1, Maximilian Haeberlin2, Simon Gross2, Benjamin Dietrich2, Jonas Reber2, Thomas Schmid2, and Klaas P Pruessmann2

1Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Zurich, Switzerland, 2Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

Tracking head mounted NMR markers enables to carry out prospective motion correction for brain MRI. In this work, a NMR marker tracking method that facilitates easy deployment is characterized with respect to tracking reliability in the presence of hardware drift and other imperfections. The method is then applied to a high-resolution in-vivo scan with long scan duration.

69
8:51
Intra echo train correction for constant flip angle Turbo Spin Echo sequence
Xiang Gao1, Patrick Hucker1, Juergen Hennig1, and Maxim Zaitsev1

1Department of Radiology, Medical Physics, Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany

Turbo spin echo (TSE) sequence is one of the “workhorses” used in routine clinical applications for MR imaging [1]. However, long scan time and segmented k-space acquisition make it particularly susceptible to artifacts due to motion, not only between echo trains but also during echo train. When correcting such motions prospectively, a signal loss might be induced due to noise in motion tracking data. In this work, we present an analysis linking tracking noise to the signal drop. A sequence optimization approach predicts that intra-echo train motion correction with the available optical tracking system should be feasible without signal loss.

70
9:03
Free-breathing placental and fetal MR angiography using continuous stable state acquisition (Sweep)
Laurence H Jackson1, Anthony N Price1, Jana Hutter1, Alison Ho2, Thomas A Roberts1, Laura McCabe1,3, Maria Deprez1, Lucy Chappell2, Mary Rutherford1,3, and Joseph V Hajnal1,3

1Biomedical Engineering,School of Biomedical Engineering & Imaging Sciences, Kings College London, London, United Kingdom, 2Department of Women and Children’s Health, School of Life Course Sciences, Kings College London, London, United Kingdom, 3Centre for the Developing brain, School of Biomedical Engineering & Imaging Sciences, Kings College London, London, United Kingdom

Major obstetric complications such as pre-eclampsia and intrauterine growth restriction can result from malformations in the circulation of the fetus and placenta. Robust, high resolution in-utero MR angiography has the potential to be a valuable tool in identification and monitoring of these disorders but is hampered by the presence of complex motion, ineffective breath holds and lack of safe contrast agents. Here we present a motion compensated method for visualising the vascular networks in the fetus and placenta using respiration resolved 2D inflow angiography with efficient and dense spatiotemporal sampling and retrospective correction.

71
9:15
Propeller Echo-Planar Time-resolved Imaging with Dynamic Encoding (PEPTIDE)
Merlin J Fair1, Fuyixue Wang1,2, Zijing Dong1,2, Berkin Bilgic1, Timothy G Reese1, and Kawin Setsompop1,2

1A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States, 2Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, United States

Echo-Planar Time-resolved Imaging (EPTI) is a recent multi-shot EPI-based approach that allows extremely rapid acquisition of distortion and blurring free multi-contrast imaging and mapping. In this work, a motion robust extension to EPTI, termed PEPTIDE, is presented. Combining Propeller-like rotations into the EPTI sampling strategy, this technique brings significant tolerance to shot-to-shot motion and B0 phase variations, as well as opening up opportunities for further acceleration.

72
9:27
Motion-insensitive 3D T2*-weighted MRI using a motion- and B0 field-navigator
Jiaen Liu1, Peter van Gelderen1, Jacco A. de Zwart1, and Jeff H. Duyn1

1National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States

The ability of T2*-weighted (or susceptibility-weighed) MRI to provide structural and functional information about the brain is affected by B0 field fluctuations associated with head motion, which are inadequately accounted for in current correction approaches. Here, a 3D EPI navigator was developed to measure head motion, map the associated complex B0 field changes and correct their effects in T2*-weighted GRE MRI. Adequate temporal resolution of the navigator was achieved by implementing 2D parallel imaging with controlled aliasing. A fast reconstruction strategy is proposed to retrospectively correct the motion artifacts, overcoming limitations of prospective B0 corrections inadequately dealing with the spatially complex B0 changes.

73
9:39
Pilot tone-based prospective respiratory motion correction for 2D cine cardiac MRI
Juliane Ludwig1, Peter Speier2, Frank Seifert1, Tobias Schaeffter1, and Christoph Kolbitsch1

1Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany, 2Siemens Healthcare, Erlangen, Germany

Respiratory motion during data acquisition can introduce strong motion artefacts in 2D cine cardiac MR images. The commonly used breathhold method minimizes these artefacts, but also limits achievable image resolution and requires patient cooperation. Here we present a prospective motion correction technique using RF pilot tone signals with high temporal resolution. A calibration scan was carried out to convert signal intensity changes of the pilot tone to displacements of the heart due to breathing. The proposed approach was evaluated in four healthy volunteers and allowed for free-breathing 2D cine MR with high image quality.

74
9:51
Network Accelerated Motion Estimation and Reduction (NAMER): Accelerating forward model based retrospective motion correction using a convolutional neural network
Melissa W. Haskell1,2, Stephen F. Cauley1,3, Berkin Bilgic1,3, Julian Hossbach4, Josef Pfeuffer4, Kawin Setsompop1,3,5, and Lawrence L. Wald1,3,5

1A.A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2Program in Biophysics, Harvard University, Cambridge, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Siemens Healthineers AG, Erlangen, Germany, 5Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, MA, United States

Retrospective motion correction techniques have the potential to improve clinical imaging without altering the workflow or acquisition sequence.  Yet, they suffer from long reconstruction times and poor conditioning. To address these problems, we developed a Network Accelerated Motion Estimation and Reduction method (NAMER) within a data-consistency based forward model approach to motion parameter estimation. The neural net accelerates convergence up to 15-fold as well as improving final image quality. The ML+MR physics motion correction method combines the speedup provided by fast convolutional neural networks with the robustness of a forward model-based data-consistency reconstruction.

75
10:03
Retrospective motion correction using deep learning
Thomas Kuestner1,2,3, Bin Yang3, Fritz Schick2, Sergios Gatidis2, and Karim Armanious2,3

1School of Biomedical Engineering & Imaging Sciences, King's College London, London, United Kingdom, 2Department of Radiology, University Hospital Tübingen, Tübingen, Germany, 3Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany

Motion is the main extrinsic source for imaging artifacts which can strongly deteriorate image quality and thus impair diagnostic accuracy. Numerous motion correction strategies have been proposed to mitigate or capture the artifacts. These methods have in common that they need to be applied during the actual measurement procedure with already a-priori knowledge about the expected motion type and appearance. We propose the usage of deep neural networks to perform retrospective motion correction in a reference-free setting, i.e. not requiring any a-priori motion information. Feasibility and influences of motion type and origin as well as optimal architecture are investigated.


Oral

Traumatic Brain Injury

Room 513D-F
Monday 8:15 - 10:15
Moderators: Brenda Bartnik Olson & Seung Hong Choi
76
8:15
Metabolic Imaging of Traumatic Brain Injuries Using Ultrahigh-Resolution 1H-MRSI
Tianyao Wang1, Jun Liu1, Tianxiao Zhang2, Ziyu Meng2, Danni Wang2, Ke Xue2, Yudu Li3,4, Rong Guo3,4, Yibo Zhao3,4, Xin Yu5, Zhi-Pei Liang3,4, and Yao Li2

1Radiology Department, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China, 2Institute for Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China, 3Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 4Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States, 5Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States

Traumatic brain injury (TBI) is a significant public health problem that contributes to a large number of injury-induced deaths each year. MRSI has long been recognized as a powerful tool for detection of neurometabolic alterations induced by TBI; however, most existing MRSI studies of TBI are limited by low resolution which severely reduce the detection sensitivity. In this study, we performed MRSI scans on TBI patients using a newly developed ultrahigh-resolution 1H-MRSI technique. Our experimental study yielded very encouraging results and showed that ultrahigh-resolution MRSI can capture neurometabolic alterations induced by TBI effectively.

77
8:27
Connectivity Reorganization after Repetitive Mild Traumatic Brain Injury is Impact Site Associated
Yu-Chieh Jill Kao1,2,3, Chia-Feng Lu4, Bao-Yu Hsieh5, and Cheng-Yu Chen1,2,3,6

1Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan, 2Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, 3Translational Imaging Research Center, Taipei Medical University Hospital, Taipei, Taiwan, 4Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan, 5Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, 6Department of Medical Imaging, Taipei Medical University Hospital, Taipei, Taiwan

Different degrees of functional reorganization associated with impact site was unraveled in the acute and chronic phase in the well-controlled animal model of repetitive mTBI. This is the first demonstration of impact site-dependent connectivity alteration without significant parenchymal damage after mTBI in rats.

78
8:39
Free water elimination is necessary to characterize Diffuse Axonal Injury in moderate Traumatic Brain Injury
Jacob Alappatt1, Drew Parker1, Abdol Aziz Ould Ismail1, Junghoon Kim2, and Ragini Verma1

1Penn Patho-Connectomics Lab, Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Molecular, Cellular, and Biomedical Sciences, CUNY School of Medicine, The City College of New York, New York, NY, United States

As the prevalence of diffusion MRI for clinical use grows, it is important to address the influence of injury-related extracellular water on the clinical interpretation of  diffusion measures in conditions such as traumatic brain injury (TBI). The presence of extracellular free water from edema pollutes the estimation of diffusion measures, leading to flawed conclusions about the microstructure of the white matter. We demonstrate that Fernet, a robust single-shell free-water elimination method, can be used to decouple the effects of extracellular edema and tissue damage, to improve clinical understanding of the effects of injury on underlying white matter structure. 

79
8:51
White matter changes caused by mild traumatic brain injury in mice
Lisa M Gazdzinski1, Miranda Mellerup1,2, Tong Wang1,2, John G Sled3,4, Brian J Nieman3,4, and Anne L Wheeler1,2

1Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON, Canada, 2Physiology, University of Toronto, Toronto, ON, Canada, 3Mouse Imaging Centre, Hospital for Sick Children, Toronto, ON, Canada, 4Medical Biophysics, University of Toronto, Toronto, ON, Canada

White matter pathology following mild traumatic brain injury (mTBI) is complex and unlikely to be characterized by a single neuroimaging metric. DTI has been used to probe white matter microstructure, but is known to be non-specific. We show that the orientation dispersion index from the NODDI model may be more sensitive to white matter damage following mTBI in a mouse closed-skull impact model. Combined with quantitative susceptibility mapping, our data suggest minimal overt myelin loss, but progressive white matter injury, which may include myelin disruption, up to 6 weeks post-mTBI.

80
9:03
Exploring static and dynamic functional connectivity differences between cognitively impaired and non-impaired active professional fighters
Xiaowei Zhuang1, Virendra Mishra1, Yang Zhengshi1, Karthik Sreenivasan1, Charles Bernick1, and Dietmar Cordes1,2

1Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV, United States, 2University of Colorado Boulder, Boulder, CO, United States

Both static and dynamic FC differences between cognitively impaired and non-impaired active fighters were explored using resting-state fMRI. Reduced network strength in anterior default mode network and cerebellar network were observed in impaired fighters, as compared to the non-impaired fighters. Four dynamic FC states were identified with k-means clustering and abnormities in state 2 were observed in impaired fighters. Higher classification accuracy was obtained using dynamic FC matrices as input features to a non-linear classifier, as compared to using static FC matrices as input features, which demonstrates that the time-varying brain activities carry richer cognitive impairment-related information.

81
9:15
In vivo magnetic resonance imaging demonstrates that subcutaneous administration angiotensin-(1-7) is neuroprotective following severe traumatic brain injury in mice
Zachary Janatpour1, Asamoah Bosomtwi2,3, Alexandru Korotcov2,3, Andrew Knutsen2,3, Shalini Jaiswal 2,3, Nathanael Allison2,4, Aviva J Symes1,4, and Bernard Dardzinski2,4

1Pharmacology and Molecular Therapeutics, Program in Molecular and Cell Biology, Uniformed Services University, Bethesda, MD, United States, 2Radiology and Radiological Sciences, Uniformed Services University, Bethesda, MD, United States, 3Center for Neuroscience and Regenerative Medicine, Henry M. Jackson Foundation, Bethesda, MD, United States, 4Center for Neuroscience and Regenerative Medicine, Uniformed Services University, Bethesda, MD, United States

The effectiveness of angiotensin-(1-7), a novel peptide derivative of angiotensin II, for the treatment of traumatic brain injury in mice have been investigated using non-invasive MRI techniques. Our results demonstrate that treatment of mice with angiotensin-(1-7) after control cortical impact reduced lesion volume compared to saline-treated mice. The MRI data are validated by histological results. The observed data show for the first time that angiotensin-(1-7) has potential therapeutic use for TBI.

82
9:27
Advanced diffusion-weighted imaging reveals distinct neuropathological processes in concussed youth
Guido Ivan Guberman1, Jean-Christophe Houde2, Isabelle Gagnon3, Alain Ptito1, and Maxime Descoteaux2

1Neurology and Neurosurgery, McGill University, Montreal, QC, Canada, 2Computer Science, University of Sherbrooke, Sherbrooke, QC, Canada, 3Pediatrics, Montreal Children's Hospital, Montreal, QC, Canada

Because concussions are undetectable by conventional medical imaging, their diagnosis is dependent on symptoms, which can be unreliable. Conventional diffusion-weighted imaging (DWI) can detect abnormalities in concussed individuals, but lack specificity and hence cannot provide information about the underlying neuropathology, especially during the sub-acute stage of concussions where different neuropathologies occur simultaneously. In this study, we used emerging DWI methods to disambiguate the neuropathological basis of a common concussive symptom, memory problems. We found evidence of different white-matter neuropathologies in concussed youth which contributed differently to memory problems. This study is an important step towards developing neuropathologically-informed biomarkers of concussion.

83
9:39
Traumatic Brain Injury fast-forwards Alzheimer's parthenogenesis: A radiological-pathological investigation in a mouse AD model.
Neha Soni1, Rodrigo Medeiros1, and Fatima Nasrallah1

1The Queensland Brain Institute, The University of Queensland, Brisbane, Australia

Traumatic brain injury (TBI) today is the strongest epigenetic risk factor for Alzheimer's disease (AD) . To date, the underlying mechanisms of these comorbidities are still unclear, which has hindered diagnosis and monitoring. We have investigated the effect of TBI in a PR5 tauopathy model using Diffusion Tensor Imaging and histology. We concluded that neuroinflammation is a key trigger in worsening taupathy accumulation and MRI can detect this cascade of events at an early stage. This study will enhance our understanding, not only of the effect of TBI progression in AD, but the potential of MRI for translational purposes.

84
9:51
Mild traumatic brain injury accelerates progressive brain ageing
Shuoqiu Gan1,2, Wen Shi2, Yingxiang Sun1, Lijun Bai2, and Ming Zhang1

1Department of Medical Imaging, the First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, China, Xi'an, Shaanxi, China, 2The Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi’ an Jiaotong University, Xi’ an, 710049, China, Xi'an, Shaanxi, China

To analyze mild traumatic brain injury (mTBI) accelerating brain ageing, we trained a brain age prediction model based on diffuse tensor image (DTI) data by using machine learning method. Conducting a longitudinal observation from acute to chronic stages, we found that mTBI accelerated brain age process from acute stage to chronic stage. This prolonged abnormal brain ageing level could be predicted by information processing speed. In conclusion, mTBI persistently induces brain ageing process deviating from normal trajectory, and this process can be revealed by information processing speed at very early period after injury.

85
10:03
Changes In White Matter Microstructure In Relation To Working Memory After Mild Traumatic Brain Injury: Multi-Shell Diffusion MRI Study
Sohae Chung1,2, Els Fieremans1,2, Xiuyuan Wang1,2, Dmitry S. Novikov1,2, Prin X. Amorapanth3, Steven R. Flanagan3, Joseph F. Rath3, and Yvonne W. Lui1,2

1Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, NYU School of Medicine, New York, NY, United States, 2Bernard and Irene Schwartz Center for Biomedical Imaging, NYU School of Medicine, New York, NY, United States, 3Department of Rehabilitation Medicine, NYU School of Medicine, New York, NY, United States

Working memory is a critical cognitive functions affected after mild traumatic brain injury (MTBI). We investigate associations between white matter (WM) microstructure and working memory, using multi-shell diffusion MRI and WAIS-IV subtests. The significant positive correlations observed in normal controls (NC) between tissue microstructure markers (fractional anisotropy (FA) and axonal water fraction (AWF)) with letter-number sequencing (LNS) were not present in MTBI. For MTBI, a significant positive correlation was observed between axial kurtosis (AK) and digit span backward (DSB), not seen in NC. These results show clear differences in the relationship between  WM microstructure and working memory performance after injury.


Oral

Advances in Flow Imaging

Room 516C-E
Monday 8:15 - 10:15
Moderators: Michael Hope & Ruth Lim
86
8:15
Acute effects of nicotine-free e-cigarette aerosol inhalation on vascular function detected by multi-parametric quantitative MRI
Alessandra Caporale1, Michael C Langham1, Shampa Chatterjee2, Alyssa C Johncola1, and Felix W Wehrli1

1Radiology, Laboratory for Structural, Physiologic and Functional Imaging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States, 2Institute for Environmental Medicine and Department of Phisiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States

Electronic cigarette (e-cig) vaping has been causally associated with arterial stiffening, oxidative stress, and impaired vasodilatory capacity. Here we investigated acute effects of nicotine-free e-cig vaping in terms of aortic pulse-wave velocity, a marker of arterial stiffness, and measures of peripheral and neurovascular reactivity to induced hypoxia, by means of a quantitative MRI protocol. Flow mediated dilation, a marker of endothelial function, was significantly impaired after vaping; moreover, the peripheral vascular response to cuff-induced ischemia and neurovascular reactivity were altered. Considering the increasing use of e-cig among youth, these results underscore the urgency of further investigation.

87
8:27
Stochastic Flow Co-expression Signatures: A novel concept for volumetric 4D flow assessment with application to aortic valve disease
Mohammed S.M. Elbaz1, Michael B. Scott1, Alex J. Barker2, Patrick McCarthy3, Chris Malaisrie3, Jeremy D. Collins4, Robert O. Bonow5, James Carr1, and Michael Markl1

1Radiology, Northwestern University, Chicago, IL, United States, 2University of Colorado, Anschutz Medical Campus, Aurora, Colo., CO, United States, 3Cardiac Surgery, Northwestern University, Chicago, IL, United States, 4Mayo Clinic, Rochester, MN, United States, 5Cardiology, Northwestern University, Chicago, IL, United States

Studies have shown an impact of aortic valve disease, as bicuspid aortic valve (BAV), on altered aortic blood flow. Nevertheless, aortic flow changes can be complex making objective visual assessment a challenging task. Existing quantitative flow metrics are useful, but each reflects only partial components of the overall complex flow changes. Here we propose a novel concept that uniquely captures the signature of normal and altered volumetric aortic flow changes derived from 4D Flow MRI. We demonstrated the high reproducibility and the feasibility of the derived flow signature in capturing distinctly altered flow signatures in the aorta of BAV patients.

88
8:39
Machine learning for automatic three-dimensional segmentation of the aorta in 4D flow MRI
Martijn Froeling1, Emile S. Farag2, R. Nils Planken3, Tim Leiner1, and Pim van Ooij3

1Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 2Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, AMC, Amsterdam, Netherlands, 3Department of Radiology & Nuclear Medicine, Amsterdam University Medical Centers, AMC, Amsterdam, Netherlands

In this study we present a machine learning convolutional neural network (CNN) for automatic segmentation of the aorta used for peak systolic wall shear stress (WSS) assessment from 4D flow MRI data. The automated three-dimensional WSS profiles (WSSMACHINE) were compared with WSS calculated using manually (WSSMAN) created segmentations. Bland-Altman and orthogonal regression analysis revealed good agreement between WSSMAN and WSSMACHINE in terms of small mean differences and slopes and intercepts close to unity and zero respectively. The CNN has the ability to drastically accelerate aortic segmentation from 4D flow MRI data, which will greatly improve the clinical applicability of WSS.

89
8:51
5D Flow Tensor MRI for Mapping Reynolds Stresses in the Aorta
Jonas Walheim1, Hannes Dillinger1, and Sebastian Kozerke1

1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

We present a 5D Flow MRI approach for mapping the Reynolds stress tensor in the in-vivo aorta within 6 minutes. First and second statistical moments of fluctuating velocities are encoded using six different velocity encoding gradient directions embedded in a Cartesian Golden angle undersampling scheme with data-driven motion detection and locally low-rank imaging reconstruction. It is demonstrated that this approach permits a time-efficient assessment of velocity vector fields, turbulent kinetic energy and Reynolds shear stresses of the aorta in-vivo.

90
9:03
5D flow MRI: A free-running, fully self-gated, radial imaging framework for cardiac and respiratory motion-resolved assessment of 3D blood flow dynamics
Liliana Ma1,2, Jérôme Yerly3, Christopher W Roy3, Davide Piccini3,4, Lorenzo Di Sopra3, James Carr1, Matthias Stuber3, and Michael Markl1,2

1Radiology, Northwestern University, Chicago, IL, United States, 2Biomedical Engineering, Northwestern University, Evanston, IL, United States, 3Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, 4Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland

Recent advances have enabled fully self-gated high resolution imaging using a Free-running framework, where data is continuously collected, retrospectively binned into cardiac and respiratory phases, and reconstructed using multi-dimensional compressed sensing (CS) for efficient functional and anatomical imaging of the heart. Here, we propose a novel expansion of this framework to cardiac and respiratory motion-resolved 3D flow imaging— or 5D flow MRI. The findings of this study show that 5D flow MRI is feasible in-vitro and in-vivo and can depict cardiac and respiratory-resolved 3D hemodynamics.

91
9:15
Chronological 4D Flow MRI Assessment of Pulmonary Artery Stenosis Stent Treatment
Ryan Pewowaruk1, Klarka Mendrisova2, Luke Lamers3, Chris Francois4, and Alejandro Roldán-Alzate1,2,4

1Biomedical Engineering, University of Wisconsin - Madison, Madison, WI, United States, 2Mechanical Engineering, University of Wisconsin - Madison, Madison, WI, United States, 3Pediatrics, University of Wisconsin - Madison, Madison, WI, United States, 4Radiology, University of Wisconsin - Madison, Madison, WI, United States

Branch pulmonary artery stenosis, a common complication after surgical repair of congenital heart disease, is treated with intravascular stenting. As the acute and chronic effects of stenting are unknown this study uses 4D Flow MRI to serially monitor hemodynamics in a porcine model of pulmonary artery stenosis. Intervention increases flow through the stenosed artery, but not to a normal value. Chronologically, stenosis flow is found to increase immediately after stenting and then remain constant.

92
9:27
4D Flow MRI Quantification of Congenital Shunts: Comparison to Invasive Catheterization
Daniel Kupsky1, Howaida El-Said1, Laith Alshawabkeh1, Seth Kligerman2, and Albert Hsiao2

1Cardiovascular Medicine, Univeristy of California San Diego, San Diego, CA, United States, 2Radiology, University of California San Diego, San Diego, CA, United States

When used for quantification of intracardiac and extracardiac shunts, 4D Flow MRI has been shown to have high reproducibility between measurement location and observers, and high consistency with MRI measurements of stroke volume. However, there has been little data showing its relationship to invasive measurements obtained during catheter angiography, which serves as the clinical reference standard at many institutions. We retrospectively evaluated patients who underwent 4D Flow MRI and invasive right heart catheterization during clinical work-up of congenital heart disease.  4D Flow measurements correlated extremely well with invasive measurements of shunt fraction by oximetry and cardiac output by Fick calculation in patients without a shunt. 

93
9:39
Comprehensive hemodynamic assessment in non-sedated neonates with CHD using motion-robust 3D radial phase-contrast MR
Eric Schrauben1, Jessie Mei Lim2, Datta Goolaub3, Davide Marini4, Michael Seed4,5, and Christopher K Macgowan1,3

1Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada, 2Physiology, University of Toronto, Toronto, ON, Canada, 3Medical Biophysics, University of Toronto, Toronto, ON, Canada, 4Heart Centre, The Hospital for Sick Children, Toronto, ON, Canada, 5Paediatrics, University of Toronto, Toronto, ON, Canada

The complex hemodynamics in congenital heart disease (CHD) are difficult to visualize and quantify in neonates and young infants. Here we present a novel motion robust and respiratory-resolved acquisition and reconstruction pipeline that addresses the need for rapid, high spatial resolution imaging in these patients. 3D cardiac flow is visualized and quantification comparison with 2D PC measurements is exhibited. This technique opens the door for more comprehensive investigations into the wealth of hemodynamic information not normally considered in surgical planning and follow-up evaluations of CHD.  

94
9:51
Sensitivity Study of 4D flow Left Ventricular Hemodynamics Parameters in Healthy Volunteers and Dilated Cardiomyopathy Patients
Pamela Alejandra Franco1,2,3, Julio Sotelo1,2,3, Bram Ruijsink4, David Nordsletten4, Eric Kerfoot4, Joaquín Mura1,2, Cristian Tejos1,2,3, Daniel Hurtado1,5,6, and Sergio Uribe1,2,6,7

1Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile, 2Biomedical Imaging Center, Pontificia Universidad Católica de Chile, Santiago, Chile, 3Electrical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile, 4Biomedical Engineering, King's College London, London, United Kingdom, 5Structural and Geotechnical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile, 6Institute for Biological and Medical Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile, 7Radiology Department, Pontificia Universidad Católica de Chile, Santiago, Chile

Segmentation of the Left Ventricle (LV) from MRI and 4D flow datasets is an essential step for quantifying clinical indices and hemodynamic parameters. Automatic methods for heart segmentation are generally validated using cardiac volumetric and global ejection fraction. However, little is known about the changes of hemodynamic parameters when subjected to different segmentations. In this study, we present a sensitivity assessment of left intraventricular hemodynamic parameters in healthy volunteers and Dilated Cardiomyopathy (DCM) patients using a finite element quantification approach using 4D flow MRI data, when subjected to changes of LV segmentations.

95
10:03
Simultaneous Measurement of Myocardial and Blood Flow Velocities using a Dual Echo Dual Velocity Encoding (DEDV) Phase-Contrast MRI (PC-MRI) Approach for Evaluating Left Ventricular (LV) Diastolic Function
Afis AJALA1,2, Jiming Zhang2, Erick Buko1,2, Luning Wang3, Debra Dees2, Janie Swaab2, Benjamin Cheong2, Pei-Herng Hor4, and Raja Muthupillai2

1Department of Physics, University of Houston [Main Campus], Houston, TX, United States, 2Department of Diagnostic and Interventional Radiology, Baylor St. Luke's Medical Center, Houston, TX, United States, 3Philips Healthcare, Gainesville, FL, United States, 4Physics and Texas Center for Superconductivity, University of Houston [Main Campus], Houston, TX, United States

PC-MRI based Left ventricular (LV) diastolic indices such as E/Em ratio are conventionally estimated from two separate PC acquisitions: One sensitive to myocardium and the other to blood velocities. This ensures optimal velocity to noise ratio and zero velocity aliasing. A rapid single acquisition (dual echo dual VENC PC-MRI method) sensitive to both low and high velocities was developed. Preliminary result on 7 healthy subjects demonstrated a high agreement of LV diastolic indices  obtained from the proposed and conventional method.


Oral

Female Pelvis

Room 518A-C
Monday 8:15 - 10:15
Moderators: Johannes Heverhagen & Rebecca Rakow-Penner
96
8:15
Technical Feasibility of Three-Dimensional Magnetic Resonance Elastography for Assessing Endometrial Carcinoma
Xi Long1, Tianhui Zhang1, Sichi Kuang1, Ying Deng1, Bingjun He1, Jingbiao Chen1, Phillip Rossman2, Kevin J Glaser2, Sudhakar K Venkatesh2, Bing Wu3, Richard L Ehman2, and Jin Wang1

1Department of Radiology, The third affiliated hospital of Sun Yat-sen University, Guangzhou, China, 2Department of Radiology, Mayo Clinic, Rochester, MN, United States, 3MR Research China, GE Healthcare, Beijing, China

Endometrial carcinoma (EC) is one of the most common primary malignant tumors in women worldwide. Tumor grades, International Federation of Gynecology and Obstetrics (FIGO) stage and myometrial invasion of EC are important factors for treatment planning and prognosis. We explored the potential value of MR elastography (MRE) for the prediction of tumor grades, FIGO stage and myometrial invasion of EC. Our study showed that mean tumor stiffness may be a useful metric for differentiating well or moderately differentiated EC from poorly differentiated EC and for differentiating superficial invasion from deep myometrial invasion in EC.

97
8:27
Value of R2* and T2* in differential diagnosis of uterine sarcoma and degenerated hysteromyoma
Miao Niu1, Ailian Liu1, and Lizhi Xie2

1The First Affiliated Hospital of Dalian Medical University, DaLian, China, 2GE Healthcare, MR Research, Beijing, China

To investigate the clinical value of enhanced T2 star weighted angiography (ESWAN) quantitative parameters in differential diagnosis of uterine sarcoma and degenerated hysteromyoma.


98
8:39
High b-value diffusion-weighted MRI in cervical cancer detection: Preliminary results
Kaibao Sun1, Qi Zhang2, Zheng Zhong1,3, Muge Karaman1,3, Xiaoduo Yu2, Han Ouyang2, and Xiaohong Joe Zhou1,3,4

1Center for MR Research,University of Illinois at Chicago, Chicago, IL, United States, 2Department of Diagnostic Radiology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, 3Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, 4Departments of Radiology and Neurosurgery, University of Illinois at Chicago, Chicago, IL, United States

Cervical cancer remains one of the leading causes of cancer-related deaths in women. High b-value DWI with non-Gaussian modeling has made it possible to probe tumor tissue complexity, microstructures, and heterogeneity. We employed a non-Gaussian diffusion model based on continuous-time random walk (CTRW) theory to differentiate normal from cancerous cervical tissues. The CTRW parameters (Dm and β) exhibited a statistically significant difference between cancerous cervical tissue and normal. Our preliminary results illustrate the added value of high b-value DWI for cervical cancer detection, and point to a possible direction of diagnosing or staging cervical cancer using non-Gaussian diffusion models.

99
8:51
Three-Dimensional Amide Proton Transfer MR Imaging for Cervical Cancer: Initial Experience
Yong-Lan He1, Cheng-Yu Lin1, Ya-Fei Qi1, Xiaoqi Wang2, Hai-Long Zhou1, Hua-Dan Xue1, and Zheng-Yu Jin1

1Peking Union Medical College Hospital, Beijing, China, 2Philips Healthcare China, Beijing, China

The present study demonstrates the feasibility of 3D APT MR imaging for uterine cervix on the largest sample size to our knowledge. As the clinical robustness of APT imaging in the pelvis is what researchers concerned, our study investigated and revealed the excellent agreement in both image quality assessment and APT values measurement, even on small cervical lesions with maximum diameter less than 2cm. Our studies demonstrated that APT imaging could differentiate cervical cancer from normal cervix. Cervical cancer showed significant higher APT values than that of normal cervix.

100
9:03
Radiomics Analysis of tumor and peri-tumor tissue on T2-Weighted Imaging Improves Diagnostic Performance of Lymph Node Metastasis in Patients with Cervical Cancer
Qingxia Wu1, Shuo Wang2, Xi Chen3, Yan Wang1, Yusong Lin4, and Meiyun Wang1

1Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China, 2CAS Key Laboratory of Molecular Imaging, Institute of Automation, Beijing, China, 3School of Information and Electronics, Beijing Institute of Technology, Beijing, China, 4Cooperative Innovation Center of Internet Healthcare & School of Software and Applied Technology, Zhengzhou University, Zhengzhou, China

The tumor margin and peritumoral tissue play an important role in the process of LN metastasis. The aim of this study was to utilize radiomics analysis of tumor and peri-tumor tissue on T2 weighted image (T2WI) to improve LNM prediction ablility in cervical cancer patients. We found that peritumoral tissue of cervical cancer on T2WI showed favorable value in predicting LNM. The decision tree we proposed which incorporates the radiomics features of intratumoral and peritumoral tissue on T2WI and c-LN status can be potentially used for personalized preoperative evaluation of LNM and optimal treatment regimen selection in cervical cancer patients. 

101
9:15
Prediction of Neoadjuvant Chemoradiation Therapy Response in Rectal Cancer Using Radiomics Compared to Deep Learning Based on Pre-Treatment and mid-RT MRI
Yang Zhang1, Liming Shi2, Ke Nie3, Xiaonan Sun2, Tianye Niu2, Ning Yue3, Tiffany Kwong1,3, Peter Chang1, Daniel Chow1, Jeon-Hor Chen1,4, and Min-Ying Lydia Su1

1Department of Radiological Sciences, University of California, Irvine, CA, United States, 2Department of Radiation Oncology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China, 3Department of Radiation Oncology, Rutgers-The State University of New Jersey, New Brunswick, NJ, United States, 4Department of Radiology, E-Da Hospital and I-Shou University, Kaohsiung, Taiwan

The capability to predict patients’ response to neoadjuvant chemoradiation therapy is important for improving their management. The multi-parametric MRI (T2, DWI, DCE) performed before treatment and after 3-4 weeks of radiation were analyzed to predict final pathological response. Quantitative radiomics was performed using GLCM texture and histogram parameters, and also ROI and deep learning using convolutional neural network (CNN) were performed. Combining quantitative radiomics features with tumor volume and diffusion coefficient could achieve accuracy of 0.86 for pCR vs. non-pCR and 0.93 for GR vs. non-GR, and adding follow-up to pre-treatment MRI could improve accuracy, especially for CNN analysis.

102
9:27
The feasibility of matching  lymph nodes detected on USPIO-enhanced MRI with histopathology in rectal cancer
Rutger C.H. Stijns1, Bart W.J. Philips1, Iris D. Nagtegaal2, Fatih Polat3, Johannes H.W. de Wilt4, Carla A.P. Wauters5, Patrik H.W. Zamecnik6, Jurgen J. Futterer1, and Tom W.J. Scheenen1

1Radiology, Radboudumc, Nijmegen, Netherlands, 2Pathology, Radboudumc, Nijmegen, Netherlands, 3Surgery, Cansius-Wilhelmina hospital, Nijmegen, Netherlands, 4Surgery, Radboudumc, Nijmegen, Netherlands, 5Pathology, Cansius-Wilhelmina hospital, Nijmegen, Netherlands, 6Radboudumc, Nijmegen, Netherlands

Lymph node staging in rectal cancer based on imaging is a major challenge. Node-to-node matching is crucial to determine the histopathology of lymph nodes that are detected on in-vivo MRI. A workflow of in-vivo MRI, ex-vivo MRI and MR-guided pathology was set up for lymph nodes that were characterized on USPIO-enhanced MRI. Difficulties were seen in the node-to-node matching, in despite of the use of high-resolution 3D ex-vivo MRI to link in-vivo detected nodes to final pathology.

103
9:39
Enhanced T2 Star-Weighted Angiography (ESWAN) for Differentiating Borderline From Malignant Epithelial Ovarian Tumors
Xu Han1, Meiyu Sun1, Lizhi Xie2, Kaiyu Wang2, Mengyao Wang1, and Rui Fan 1

1First Affiliated Hospital of Dalian Medical University, Dalian, China, 2GE Healthcare, Beijing, China

The aim of this study is to assess the fitted parameters of ESWAN in ovarian tumors and to investigate their potential in distinguishing borderline from malignant epithelial ovarian tumors, which can provide detailed information for clinical treatment. R2* and T2* in ESWAN were the key parameters for distinguishing borderline from malignant epithelial ovarian tumors. MR-ESWAN sequence can be used as non-enhancement quantitative indexes, which has a good application prospect.

104
9:51
Ex-vivo MR-guided pathology to improve lymph node staging in rectal cancer
Rutger C.H. Stijns1, Bart W.J. Philips1, Carla A.P. Wauters2, Johannes H.W. de Wilt3, Iris D. Nagtegaal4, and Tom W.J Scheenen1

1Radiology, Radboudumc, Nijmegen, Netherlands, 2Pathology, Canisius-Wilhelmina hospital, Nijmegen, Netherlands, 3Surgery, Radboudumc, Nijmegen, Netherlands, 4Pathology, Radboudumc, Nijmegen, Netherlands

Pathological lymph node yield can be influenced by multiple factors. The use of ex-vivo MR guided pathology of rectal specimens could provide insight in the number and size of lymph nodes present in a rectal specimen and aid in an increased pathological lymph node yield. Therefore two series of rectal specimens were examined, one control group and one MR-guided group. Ex-vivo­ MRI revealed significantly more and significantly smaller lymph nodes without increasing the pathological yield. Small nodes appear to be difficult to harvest, presumably requiring a 3D approach for further improvement of pathological evaluation.

105
10:03
Using Amide Proton Transferto indentify Cervical Squamous Carcinoma/Adenocarcinoma and Evaluate its Differentiation Grade
Nan Meng1, Jing Wang1, Wenling Liu1, Xuejia Wang1, Dandan Zheng2, Huijia Yin1, Hongxia Wang1, and Dongming Han*1

1Department of MR, the First Affiliated Hospital,Xinxiang Medical University, Weihui, China, 2MR Research China, GE Healthcare, Beijing, China

Amide proton transfer (APT) weighted imaging provides information about concentration of proteins/peptides with amide backbones. At present, there is no report on whether APT can be applied to cervical cancer. Our results show that APT can be used to preliminarily identify cervical squamous carcinoma, cervical adenocarcinoma and evaluate its differentiation grade.


Oral

Young Investigator Awards

Room 520A-F
Monday 8:15 - 10:15
Moderators: Houchun Hu & Natalie Serkova
106
8:15
3D R2* Mapping of the Placenta During Early Gestation Using Free-Breathing Multiecho Stack-of-Radial MRI at 3 T
Tess Armstrong1,2, Dapeng Liu1, Thomas Martin1,2, Rinat Masamed1, Carla Janzen3, Cass Wong1, Teresa Chanlaw4, Sherin U. Devaskar4, Kyunghyun Sung1,2, and Holden H. Wu1,2

1Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States, 2Physics and Biology in Medicine, University of California Los Angeles, Los Angeles, CA, United States, 3Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States, 4Pediatrics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States

Ischemic placental disease can lead to hypoxia and abnormal pregnancy outcomes. R2* mapping using MRI can characterize placental hypoxia. However, conventional Cartesian MRI requires breath-holding which limits volumetric coverage, resolution, and signal-to-noise ratio. In addition, little is known about the nominal range of placental R2* at 3T and during early gestation. Therefore, we developed and evaluated a new free-breathing 3D stack-of-radial (free-breathing radial) technique for full volume placental R2* mapping at 3T. Free-breathing radial demonstrated good repeatability and established a nominal range of placental R2* in pregnant subjects during early gestation at 3T.

107
8:35
5-Minute Double-Echo in Steady-State with Separated Echoes for Comprehensive Whole-Joint Knee MRI Assessment with and without a Proton-Density-Weighted Sequence
Akshay Chaudhari1,2, Zhongnan Fang3, Murray Grissom1, Bragi Sveinsson4,5, Jeff P. Wood1, Christopher F. Beaulieu1,6, Edwin H. G. Oei7, Jarrett K. Rosenberg1, Feliks Kogan1, Jin Hyung Lee2,8,9,10, Marcus T. Alley1, Garry E. Gold1,2,6, Kathryn J. Stevens1,6, and Brian A. Hargreaves1,2,8

1Department of Radiology, Stanford University, Stanford, CA, United States, 2Department of Bioengineering, Stanford University, Stanford, CA, United States, 3LVIS Corporation, Palo Alto, CA, United States, 4Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 5Department of Radiology, Harvard Medical School, Boston, MA, United States, 6Department of Orthopaedic Surgery, Stanford University, Stanford, CA, United States, 7Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center, Rotterdam, Netherlands, 8Department of Electrical Engineering, Stanford University, Stanford, CA, United States, 9Department of Neurology & Neurological Sciences, Stanford University, Stanford, CA, United States, 10Department of Neurology, Stanford University, Stanford, CA, United States

Most knee MRI protocols require 20+ minutes of scan time, leading to interest in expedited protocols. Here, we first demonstrate in a study with 35 patients and 5 readers that for diagnostic knee MRI, a 3D 5-minute quantitative double-echo steady-state (qDESS) sequence has high agreement with the conventional sequences, where the addition of a proton-density-weighted sequence engenders near-perfect agreement. In a second study with 51 patients and 2 readers, we demonstrate that qDESS with two-fold enhanced slice resolution using deep-learning-based super-resolution and T2 maps has high agreement with the conventional sequences, where both methods have similar agreement with arthroscopic findings.

108
8:55
3D chemical shift-encoded MRI for volume and composition quantification of abdominal adipose tissue during an overfeeding protocol in healthy volunteers
Angéline Nemeth1, Bérénice Segrestin2,3, Benjamin Leporq1, Kevin Seyssel4, Khuram Faraz1, Valérie Sauvinet2, Emmanuel Disse2,3, Pierre-Jean Valette5, Martine Laville2,3, Hélène Ratiney1, and Olivier Beuf1

1Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F69621, Lyon, France, 2Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA), Centre Hospitalier Lyon Sud, Pierre-Bénite, Lyon, France, 3Institut National de la Santé et de la Recherche Médicale Unit 1060, CarMeN Laboratory, Lyon 1 University, Oullins, France, 4Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, France, 5Hospices Civils de Lyon, Département d'imagerie digestive, CHU Edouard Herriot, Lyon, France

The aim of this work was to assess chemical shift-encoded MRI (CSE-MRI) method to quantify content and composition changes of fat storage in healthy volunteers during a 31 days overfeeding protocol while comparing CSE-MRI results with DEXA, MRS and Gas chromatography measurements. A total of 21 volunteers underwent a NMR protocol at 3T with an axial 3D CSE-MRI on abdominal region and spectroscopy acquired on subcutaneous adipose tissue, visceral adipose tissue and liver. The NMR protocol was used to analyze the volume and the fatty acid composition of abdominal adipose tissues, and the fat content in the liver.

109
9:15
Prediction of Peripheral Nerve Stimulation Thresholds of MRI Gradient Coils using Coupled Electromagnetic and Neurodynamic Simulations
Mathias Davids1,2, Bastien Guérin2,3, Axel vom Endt4, Lothar R. Schad1, and Lawrence L. Wald2,3,5

1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany, 2Dept. of Radiology, A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Siemens Healthcare, Erlangen, Germany, 5Harvard-MIT Division of Health Sciences Technology, Cambridge, MA, United States

Peripheral Nerve Stimulation (PNS) has become the major limitation in many fast MRI sequences for state-of-the-art gradient systems. We present the first (to our knowledge) full PNS model for assessing magnetostimulation thresholds and a method to incorporate these thresholds as constraints in the coil-winding design phase. Our model consists of comprehensive female and male body models for EM simulations, co-registered atlases of peripheral nerves, and a neurodynamic model describing the nerve responses to induced electric fields. We validated our framework based on three commercial MR gradient systems and found close resemblance between simulated thresholds and experimentally obtained group PNS thresholds.

110
9:35
SPARKLING: variable-density k-space filling curves for accelerated MRI
Carole Lazarus1,2,3, Pierre Weiss4,5,6, Nicolas Chauffert1,2,3, Franck Mauconduit7, Loubna El Gueddari1,2,3, Christophe Destrieux8, Ilyess Zemmoura8, Alexandre Vignaud1,2, and Philippe Ciuciu1,2,3

1NeuroSpin, CEA Saclay, Gif-sur-Yvette, France, 2Université Paris, Saclay, France, 3Parietal, INRIA, Palaiseau, France, 4ITAV USR3505 CNRS, Toulouse, France, 5IMT UMR 5219 CNRS, Toulouse, France, 6Université de Toulouse, Toulouse, France, 7Siemens Healthineers, Saint‐Denis, France, 8Université François‐Rabelais de Tours, INSERM, Imagerie et Cerveau UMR 930, Tours, France

This work reports the use of new non-Cartesian k-space trajectories whose improved efficiency allows to significantly reduce MR scan time with minimum deterioration of image quality. Instead of using simple geometrical patterns, we introduce an approach inspired from stippling techniques, which automatically designs optimized sampling patterns along any desired density by taking full advantage of the hardware capabilities. We use our strategy to accelerate the acquisition time of T2*-weighted scans acquired at 7T on in vivo human brains. We compare our method to standard non-Cartesian trajectories (spiral, radial) and demonstrate its superiority regarding image quality and robustness to system imperfections.

111
9:55
Echo Planar Time-resolved Imaging (EPTI)
Fuyixue Wang1,2, Zijing Dong1,3, Timothy G. Reese1, Berkin Bilgic1,4, Mary Katherine Manhard1, Jingyuan Chen1, Jonathan R. Polimeni1,2,4, Lawrence L. Wald1,2,4, and Kawin Setsompop1,2,4

1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, United States, 3Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA, United States, 4Department of Radiology, Harvard Medical School, Boston, MA, United States

A new technique, termed Echo Planar Time-resolved Imaging (EPTI), was developed to address EPI’s geometric distortion and blurring, and to provide temporal signal evolution information across the EPI readout window. Using a small number of EPTI-shots, a time-series of multi-contrast images can be created free of distortion and blurring (up to 100 T2- and T2*-weighted images). This should make EPTI useful for numerous applications. Here, we demonstrated EPTI in brain to provide i) rapid simultaneous quantitative mapping of T2, T2*, proton density and tissue phase, as well as ii) multi-echo and quantitative T2* fMRI.


Member-Initiated Symposium

STOP Looking: Ultra-High Field Killer Applications Found

Organizers: Dennis Klomp, Armin Michael Nagel, Veronika Rackayova
Room 516AB
Monday 8:15 - 10:15
Moderators: Catalina Arteaga de Castro & Gregory Metzger
(no CME credit)
8:15
Let's Exchange: CEST
Peter van Zijl

8:35
Salty Treat: Sodium MRI
Claudia A.M. Gandini Wheeler-Kingshott1

1NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL Institute of Neurology, London, United Kingdom

8:55
Look at All These Different Protons: 1H MRSI
Anke Henning1

1MPI for Biological Cybernetics, Germany

9:15
Energizing Oncology: 31P MRSI
Jannie Wijnen

9:35
Drink the Tracer: Deuterium MRI
Robin A de Graaf1

1MRRC, Yale University, New Haven, CT, United States

9:55
Get Down with 2HG (Yeah You Know Me)
Alexander Lin1

1Brigham and Women's Hospital, United States


Member-Initiated Symposium

Frontiers in Magnetic Resonance Imaging Biomarkers of Renal Disease: Where Imaging Sciences, Big Data, Physiology & Medicine Meet

Organizers: Thoralf Niendorf, Octavia Bane
Room 513A-C
Monday 8:15 - 10:15
(no CME credit)
8:15
The Link to Biology & Renal Physiology: The Physiologist’s Perspective
Erdmann Seeliger

8:30
Renal Diseases & Pathophysiology: The Nephrologist’s Perspective
Madhav Menon

8:45
Emerging Renal MR Imaging Biomarkers or Measurement Approaches: The MR Physics Perspective
Charlotte Elizabeth Buchanan1

1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom

9:00
Technical Validation: Demonstrating Accuracy, Precision & Quality Assurance of Renal MR Biomarkers
Ilona Alexandra Dekkers1

1Radiology, Leiden University Medical Center, Voorburg, Netherlands

9:15
Computational Models, Predictive Analytics & Machine Learning for Advancing Renal Diagnostics & Theranostics
Satish Viswanath

9:30
Potential Added Value of Novel Renal MR Biomarkers in Drug Development or Patient Management
Lilach Lerman

9:45
Practical Challenges & Outcome of Multi-Center Studies & Clinical Renal MR Imaging Trials
Paul Hockings


Digital Poster: Engineering
Exhibition Hall
Monday 9:15 - 10:15
(no CME credit)
Plenary Session

Disruptors

Organizers: Elna-Marie Larsson, Daniel Sodickson, Kei Yamada, Xin Yu
Plenary Hall - Room 517
Monday 11:15 - 12:15
Moderators: Elna-Marie Larsson & Xin Yu
11:15
Introduction

11:20
Disruptors to the Way We Gather Data
Andrew Webb1

1Leiden University Medical Center, Netherlands

11:38
Disruptors to the Way We Visualize Data
Mark Griswold1

1Case Western Reserve University

11:57
Disruptors to the Way We Interpret Data
Hedvig Hricak


Corporate Symposium

Gold Corporate Symposium: GE Healthcare

Plenary Hall - Room 517
Monday 12:30 - 13:30
(no CME credit)

Digital YIA Poster

Digital Poster: Young Investigator Awards

ISMRM Booth on Exhibition Floor
Monday 13:45 - 15:45
(no CME credit)
106
13:45
3D R2* Mapping of the Placenta During Early Gestation Using Free-Breathing Multiecho Stack-of-Radial MRI at 3 T
Tess Armstrong1,2, Dapeng Liu1, Thomas Martin1,2, Rinat Masamed1, Carla Janzen3, Cass Wong1, Teresa Chanlaw4, Sherin U. Devaskar4, Kyunghyun Sung1,2, and Holden H. Wu1,2

1Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States, 2Physics and Biology in Medicine, University of California Los Angeles, Los Angeles, CA, United States, 3Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States, 4Pediatrics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States

Ischemic placental disease can lead to hypoxia and abnormal pregnancy outcomes. R2* mapping using MRI can characterize placental hypoxia. However, conventional Cartesian MRI requires breath-holding which limits volumetric coverage, resolution, and signal-to-noise ratio. In addition, little is known about the nominal range of placental R2* at 3T and during early gestation. Therefore, we developed and evaluated a new free-breathing 3D stack-of-radial (free-breathing radial) technique for full volume placental R2* mapping at 3T. Free-breathing radial demonstrated good repeatability and established a nominal range of placental R2* in pregnant subjects during early gestation at 3T.

107
14:05
5-Minute Double-Echo in Steady-State with Separated Echoes for Comprehensive Whole-Joint Knee MRI Assessment with and without a Proton-Density-Weighted Sequence
Akshay Chaudhari1,2, Zhongnan Fang3, Murray Grissom1, Bragi Sveinsson4,5, Jeff P. Wood1, Christopher F. Beaulieu1,6, Edwin H. G. Oei7, Jarrett K. Rosenberg1, Feliks Kogan1, Jin Hyung Lee2,8,9,10, Marcus T. Alley1, Garry E. Gold1,2,6, Kathryn J. Stevens1,6, and Brian A. Hargreaves1,2,8

1Department of Radiology, Stanford University, Stanford, CA, United States, 2Department of Bioengineering, Stanford University, Stanford, CA, United States, 3LVIS Corporation, Palo Alto, CA, United States, 4Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 5Department of Radiology, Harvard Medical School, Boston, MA, United States, 6Department of Orthopaedic Surgery, Stanford University, Stanford, CA, United States, 7Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center, Rotterdam, Netherlands, 8Department of Electrical Engineering, Stanford University, Stanford, CA, United States, 9Department of Neurology & Neurological Sciences, Stanford University, Stanford, CA, United States, 10Department of Neurology, Stanford University, Stanford, CA, United States

Most knee MRI protocols require 20+ minutes of scan time, leading to interest in expedited protocols. Here, we first demonstrate in a study with 35 patients and 5 readers that for diagnostic knee MRI, a 3D 5-minute quantitative double-echo steady-state (qDESS) sequence has high agreement with the conventional sequences, where the addition of a proton-density-weighted sequence engenders near-perfect agreement. In a second study with 51 patients and 2 readers, we demonstrate that qDESS with two-fold enhanced slice resolution using deep-learning-based super-resolution and T2 maps has high agreement with the conventional sequences, where both methods have similar agreement with arthroscopic findings.

108
14:25
3D chemical shift-encoded MRI for volume and composition quantification of abdominal adipose tissue during an overfeeding protocol in healthy volunteers
Angéline Nemeth1, Bérénice Segrestin2,3, Benjamin Leporq1, Kevin Seyssel4, Khuram Faraz1, Valérie Sauvinet2, Emmanuel Disse2,3, Pierre-Jean Valette5, Martine Laville2,3, Hélène Ratiney1, and Olivier Beuf1

1Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F69621, Lyon, France, 2Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA), Centre Hospitalier Lyon Sud, Pierre-Bénite, Lyon, France, 3Institut National de la Santé et de la Recherche Médicale Unit 1060, CarMeN Laboratory, Lyon 1 University, Oullins, France, 4Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, France, 5Hospices Civils de Lyon, Département d'imagerie digestive, CHU Edouard Herriot, Lyon, France

The aim of this work was to assess chemical shift-encoded MRI (CSE-MRI) method to quantify content and composition changes of fat storage in healthy volunteers during a 31 days overfeeding protocol while comparing CSE-MRI results with DEXA, MRS and Gas chromatography measurements. A total of 21 volunteers underwent a NMR protocol at 3T with an axial 3D CSE-MRI on abdominal region and spectroscopy acquired on subcutaneous adipose tissue, visceral adipose tissue and liver. The NMR protocol was used to analyze the volume and the fatty acid composition of abdominal adipose tissues, and the fat content in the liver.

109
14:45
Prediction of Peripheral Nerve Stimulation Thresholds of MRI Gradient Coils using Coupled Electromagnetic and Neurodynamic Simulations
Mathias Davids1,2, Bastien Guérin2,3, Axel vom Endt4, Lothar R. Schad1, and Lawrence L. Wald2,3,5

1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany, 2Dept. of Radiology, A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Siemens Healthcare, Erlangen, Germany, 5Harvard-MIT Division of Health Sciences Technology, Cambridge, MA, United States

Peripheral Nerve Stimulation (PNS) has become the major limitation in many fast MRI sequences for state-of-the-art gradient systems. We present the first (to our knowledge) full PNS model for assessing magnetostimulation thresholds and a method to incorporate these thresholds as constraints in the coil-winding design phase. Our model consists of comprehensive female and male body models for EM simulations, co-registered atlases of peripheral nerves, and a neurodynamic model describing the nerve responses to induced electric fields. We validated our framework based on three commercial MR gradient systems and found close resemblance between simulated thresholds and experimentally obtained group PNS thresholds.

110
15:05
SPARKLING: variable-density k-space filling curves for accelerated MRI
Carole Lazarus1,2,3, Pierre Weiss4,5,6, Nicolas Chauffert1,2,3, Franck Mauconduit7, Loubna El Gueddari1,2,3, Christophe Destrieux8, Ilyess Zemmoura8, Alexandre Vignaud1,2, and Philippe Ciuciu1,2,3

1NeuroSpin, CEA Saclay, Gif-sur-Yvette, France, 2Université Paris, Saclay, France, 3Parietal, INRIA, Palaiseau, France, 4ITAV USR3505 CNRS, Toulouse, France, 5IMT UMR 5219 CNRS, Toulouse, France, 6Université de Toulouse, Toulouse, France, 7Siemens Healthineers, Saint‐Denis, France, 8Université François‐Rabelais de Tours, INSERM, Imagerie et Cerveau UMR 930, Tours, France

This work reports the use of new non-Cartesian k-space trajectories whose improved efficiency allows to significantly reduce MR scan time with minimum deterioration of image quality. Instead of using simple geometrical patterns, we introduce an approach inspired from stippling techniques, which automatically designs optimized sampling patterns along any desired density by taking full advantage of the hardware capabilities. We use our strategy to accelerate the acquisition time of T2*-weighted scans acquired at 7T on in vivo human brains. We compare our method to standard non-Cartesian trajectories (spiral, radial) and demonstrate its superiority regarding image quality and robustness to system imperfections.

111
15:25
Echo Planar Time-resolved Imaging (EPTI)
Fuyixue Wang1,2, Zijing Dong1,3, Timothy G. Reese1, Berkin Bilgic1,4, Mary Katherine Manhard1, Jingyuan Chen1, Jonathan R. Polimeni1,2,4, Lawrence L. Wald1,2,4, and Kawin Setsompop1,2,4

1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, United States, 3Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA, United States, 4Department of Radiology, Harvard Medical School, Boston, MA, United States

A new technique, termed Echo Planar Time-resolved Imaging (EPTI), was developed to address EPI’s geometric distortion and blurring, and to provide temporal signal evolution information across the EPI readout window. Using a small number of EPTI-shots, a time-series of multi-contrast images can be created free of distortion and blurring (up to 100 T2- and T2*-weighted images). This should make EPTI useful for numerous applications. Here, we demonstrated EPTI in brain to provide i) rapid simultaneous quantitative mapping of T2, T2*, proton density and tissue phase, as well as ii) multi-echo and quantitative T2* fMRI.


Digital Poster: Body: Breast, Chest, Abdomen, Pelvis
Exhibition Hall
Monday 13:45 - 14:45
(no CME credit)
Study Group Business Meeting

Pediatric MR Study Group Business Meeting

Room 511A
Monday 13:45 - 14:45
(no CME credit)

Study Group Business Meeting

MR Safety Study Group Business Meeting

Room 511D
Monday 13:45 - 14:45
(no CME credit)

Weekday Course

Cardiac Microstructure

Organizers: Jennifer Keegan, Bruno Quesson
Room 512A-H
Monday 13:45 - 15:45
Moderators: Daniel Ennis & Christopher Nguyen
13:45
Understanding Cardiac Microstructure
Alistair Young1

1Biomedical Engineering, King's College London, London, United Kingdom

Detailed information can now be obtained on the microstructural architecture of the heart from MRI data. Changes in microstructure in disease have significant impacts on cardiac performance. This talk will give course participants an overview of our current understanding of the relationships between cardiac microstructure and cardiac function. Recent clinical applications will be reviewed and areas of productive future research will be highlighted.

14:15
Cardiac DTI: Acquisition Techniques
Christian Stoeck1

1University and ETH Zurich, Switzerland

The two most commonly used approaches to overcome motion induced signal dephasing in cardiac diffusion weighted imaging rely on stimulated echo acquisition mode and motion compensated spin echo diffusion weighted imaging. Both sequences employ different strategies to generate diffusion contrast. In recent in-vivo imaging as well as Monte Carlo simulations it has become apparent that the quantitative parameters such as mean diffusivity and fractional anisotropy substantially differ between the two imaging approaches. The aim of this educational is to explain motion compensation strategies and discuss the resulting differences in measurements.

14:45
Cardiac DTI: Processing Techniques
Elizabeth M. Tunnicliffe1

1University of Oxford, Oxford, United Kingdom

This talk will outline how the diffusion tensor is calculated from the diffusion weighted images. Tensor-derived invariants (mean diffusivity and fractional anisotropy) as well as cardiac-specific directional parameters will be discussed. 

15:15
Cardiac DTI: Current & Future Clinical Applications
Dudley J. Pennell1

1Royal Brompton Hospital, United Kingdom

Only one tool exists to perform in-vivo, human non-invasive assessment of the myocardium at the microstructural level, namely diffusion tensor (DT) cardiac magnetic resonance (CMR). DT-CMR quantifies water diffusion in the myocardium, which is constrained by the myocardial micro-architecture. This talk examines potential clinical applications of DT-CMR. 

15:40
Self Assessment Module (SAM)

15:45
Adjournment


Weekday Course

Idiopathic Normal Pressure Hydrocephalus: The Role of MRI

Organizers: Elna-Marie Larsson, Pia Maly Sundgren
Room 516C-E
Monday 13:45 - 15:45
Moderators: Elna-Marie Larsson & Karin Markenroth Bloch
13:45
Idiopathic Normal Pressure Hydrocephalus: Definition & Imaging
Ari Blitz1

1Johns Hopkins University, Baltimore, MD

During this presentation we will review the imaging features of adult hydrocephalus and the current limitations in our ability to provide diagnostic and prognostic information for this disease process.

14:15
MRI for Selection of Patients for Shunt Surgery & Follow-up
Karin Kockum1

1Östersund Hospital, Umeå University, Östersund, Sweden

Brain MRI has a key role in the diagnosis of idiopathic Normal Pressure Hydrocephalus and is supportive in the selection of shunt candidates. This course will present an overview of the diagnostic and prognostic value of imaging features. A systematic approach to imaging evaluation and structured reporting of the findings enables comparison between sites and longitudinal follow-up of patients.

14:45
Aqueductal Flow in iNPH
Karin Markenroth Bloch1

1Lund University Bioimaging Center, Lund University, Lund, Sweden

Idipathic Normal Pressure Hydrocephalus (iNPH) is a debilitating diesease without known cause. The symptoms are similar to those of vascular dementia, Alzheimers disease (AD) and Parkinsons (PD), making it difficult to diagnose. iNPH can be surgically treated with good results in at least a subset of patients, making a correct diagnosis crucial to the patient. Quantitative flow measurements of the cerebrospinal fluid (CSF) through the cerebral aqueduct has been suggested as a means of supporting the diagnosis of iNPH, differentiating it from AD or other forms of dementia, and for predicting outcome of ventriculoperitoneal shunting.

15:15
CSF dynamics Imaging with ASL
Shinya Yamada1

1Kugayama Hospital, Japan

I will talk about Cerebrospinal fluid dynamics observation using MRI arterial spin labeling (ASL) technique in normal brain and it’s alteration in hydrocephalic brain. Observation of CSF flow by ASL is quite different from that is described in the textbook.

15:45
Adjournment


Power Pitch

Pitch: Myelin Imaging in Sickness & Health

Power Pitch Theater A - Exhibition Hall
Monday
Pitches: 13:45 - 14:45
Posters: 14:45 - 15:45
Moderators: Alex MacKay & Melanie Martin
(no CME credit)
112
Pitch: 13:45
Poster: 14:45
Plasma 1
3D Inversion Recovery Ultrashort Echo Time (3D IR-UTE) Magnetic Resonance Imaging of Myelin in Traumatic Brain Injury – a Feasibility Study
Ya-Jun Ma1, Adam Searleman1, Shanshan Wang1, Hyungseok Jang1, Jonathan Wong2, Eric Chang1,2, Brian Head1, and Jiang Du1

1University of California, San Diego, San Diego, CA, United States, 2VA San Diego Healthcare System, San Diego, CA, United States

Reduced myelination has been observed in rodents and humans after mild traumatic brain injury (mTBI). However, conventional MR imaging sequences cannot directly detect any signal from myelin. In this study, we aimed to evaluate a 3D IR-UTE sequence for selective imaging of myelin in mice using a standard controlled cortical impact (CCI) model of mTBI with histological confirmation. To demonstrate the clinical feasibility, a translational 3D IR-UTE technique was developed and applied to healthy volunteers and mTBI patients at 3T. The preliminary results demonstrate the feasibility of volumetric myelin mapping using the 3D IR-UTE sequences at 7T and 3T.

113
Pitch: 13:45
Poster: 14:45
Plasma 2
Volumetric Imaging of Myelin in Vivo using 3D Inversion-Recovery Ultrashort Echo Time Cones (3D IR-UTE-Cones) Magnetic Resonance Imaging
Ya-Jun Ma1, Adam Searleman1, Hyungseok Jang1, Shu-Juan Fan1, Jonathan Wong2, Jody Corey-Bloom3, Eric Chang1,2, and Jiang Du1

1Radiology, University of California, San Diego, San Diego, CA, United States, 2VA San Diego Healthcare System, San Diego, CA, United States, 3Neurosciences, University of California, San Diego, San Diego, CA, United States

To image myelin directly for whole brain on clinical scanners which would provide better characterization of multiple sclerosis (MS) lesions at diagnosis and in response to therapy, we propose a 3D adiabatic inversion recovery prepared ultrashort echo time cones (3D IR-UTE-Cones) sequence for volumetric myelin imaging in vivo with a clinical feasible scan time. The myelin imaging show clearly signal loss in MS lesions for both ex vivo and in vivo brain studies.

114
Pitch: 13:45
Poster: 14:45
Plasma 3
Comparison of Myelin- and Axon-Specific Imaging Modalities in Multiple Sclerosis
Sehong Oh1, Kunio Nakamura2, Kedar Mahajan3, Jacqueline Chen2, Mark J. Lowe4, Daniel Ontaneda3, Bruce D. Trapp2, and Ken E. Sakaie4

11Division of Biomedical Engineering, Hankuk University of Foreign Studies, Yongin, Korea, Republic of, 2Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, United States, 3Neurological Institute, The Cleveland Clinic, Cleveland, OH, United States, 4The Cleveland Clinic, Cleveland, OH, United States

Multiple sclerosis (MS) is a chronic disease characterized by demyelination and neuronal/axonal pathology. Based on postmortem MRI-pathology correlations lesions found on conventional MRI do not exhibit expected demyelination. There is a need for imaging modalities that have better specificity for myelin, axonal density and axonal health.  We compare the properties of fast variants of myelin-specific modalities (myelin water imaging, quantitative magnetization transfer and visualization of short transverse relaxation component) and of axon-specific measures from neurite orientation dispersion and density imaging. These comparisons constitute steps toward developing better imaging biomarkers for MS pathology.

115
Pitch: 13:45
Poster: 14:45
Plasma 4
Reproducibility of Practical Imaging-Based Myelin Biomarkers
Sehong Oh1 and Ken E. Sakaie2

1Division of Biomedical Engineering, Hankuk University of Foreign Studies, Yongin, Korea, Republic of, 2Imaging Institute, The Cleveland Clinic, Cleveland, OH, United States

Remyelination therapies are an emerging approach for treating multiple sclerosis, but development of these therapies is hampered by a lack of imaging biomarkers. Imaging with improved specificity to myelin, as compared to conventional MRI, have the potential to act as biomarkers, but current implementations can be time consuming. We examine the performance of fast version of myelin imaging from the perspective of reproducibility, a necessary prerequisite for use in proof-of-concept clinical trials of remyelinating agents.

116
Pitch: 13:45
Poster: 14:45
Plasma 5
Chronic MS lesions with hyperintense appearance on QSM demonstrate more myelin damage and are long-lasting
Shun Zhang1,2, Thanh D. Nguyen2, Yi Wang2,3, and Susan A. Gauthier4

1Radiology, Tongji Hospital, Tongji Medical College, HUST, Wuhan, China, 2Radiology, Weill Cornell Medical College, New York, NY, United States, 3Biomedical Engineering, Cornell University, Ithaca, NY, United States, 4Neurology, Weill Cornell Medical College, New York, NY, United States

We assessed longitudinal QSM and MWF changes in 307 chronic MS lesions from 41 patients over four years. Lesions were stratified into three groups: hyperintense rim on QSM (rim+), no rim (rim-) and isointense on QSM (QSM-).  Rim+ lesions were found to have the lowest MWF. QSM lesions showed a decreasing trend while MWF remains relatively stable over the same period.

117
Pitch: 13:45
Poster: 14:45
Plasma 6
Concurrent remyelination and susceptibility increase in new active MS lesions indicate early iron accrual
Shun Zhang1,2, Yi Wang2,3, Susan A. Gauthier4, and Thanh D. Nguyen2

1Radiology, Tongji Hospital, Tongji Medical College, HUST, Wuhan, China, 2Radiology, Weill Cornell Medical College, New York, NY, United States, 3Biomedical Engineering, Cornell University, Ithaca, NY, United States, 4Neurology, Weill Cornell Medical College, New York, NY, United States

We reported initial results of an ongoing longitudinal study of new enhancing lesions using quantitative MRI including QSM, MWF and DTI. MS patients were followed five times during the first three months of lesion formation. We found a subset of lesions in which QSM rises rapidly and simultaneously with MWF and FA measurements, suggesting increasing iron accumulation within this period.

118
Pitch: 13:45
Poster: 14:45
Plasma 7
A pediatric brain template for myelin water fraction and diffusion tensor imaging.
Sarah R. Morris1,2,3, Richard Davis Holmes3, Adam V. Dvorak1,2, Hanwen Liu1,2, Irene Vavasour3, Silvia Mazabel4, Burkhard Mädler5, Shannon Kolind1,2,3,6, David K. B. Li3,6, Linda Siegel4, Christian Beaulieu7, Alex L. MacKay1,3, and Cornelia Laule1,2,3,8

1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2International Collaboration on Repair Discoveries, Vancouver, BC, Canada, 3Radiology, University of British Columbia, Vancouver, BC, Canada, 4Educational and Counseling Psychology, and Special Education, University of British Columbia, Vancouver, BC, Canada, 5Phillips Healthcare, Hamburg, Germany, 6Medicine, University of British Columbia, Vancouver, BC, Canada, 7Biomedical Engineering, University of Alberta, Edmonton, AB, Canada, 8Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada

Measuring pediatric brain myelination can provide insights into normal brain development as well as many pediatric brain disorders. We have created a myelin water and diffusion tensor template for healthy children aged 9-10 years to be used as a reference in imaging studies. Our template was produced using ANTs software to provide high-quality anatomical alignment of brain structures. ROI analysis revealed significant differences in myelin water fraction between children and adults. We found no significant correlation between myelin water fraction and diffusion tensor metrics across the ROIs investigated, highlighting the complementary information these two techniques provide.

119
Pitch: 13:45
Poster: 14:45
Plasma 8
A comparison between diffusion metrics, macromolecular proton fraction, and g-ratio for quantitative in vivo myelin mapping
Yu Veronica Sui1, Pippa Storey2, Alexey Samsonov3, and Mariana Lazar2,4

1New York University School of Medicine, New York, NY, United States, 2Department of Radiology, New York University School of Medicine, New York, NY, United States, 3Department of Radiology, University of Wisconsin at Madison, Madison, WI, United States, 4Bernard and Irene Schwartz Center for Biomedical Imaging, New York, NY, United States

Myelination as one of the most reliable indicators of postnatal brain maturation and cognitive ability, supports white matter function by facilitating efficient neural signaling and pathway remodeling. The current study aimed to compare in healthy young adults several recently developed myelin mapping metrics including g-ratio, macromolecular proton fraction, and metrics from diffusion tensor/kurtosis imaging. Relationships between these individual metrics and their specific sensitivity to different aspects of white matter microstructure are discussed.

120
Pitch: 13:45
Poster: 14:45
Plasma 9
Test-retest Reliability of Myelin-Sensitive MRI Techniques
Kiara A. Kunimoto1,2, Bryce L. Geeraert2,3, R. Marc Lebel2,4,5, and Catherine Lebel2,4

1Health Sciences Progam, University of Calgary, Calgary, AB, Canada, 2Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada, 3Biomedical Engineering Graduate Program, University of Calgary, Calgary, AB, Canada, 4Department of Radiology, University of Calgary, Calgary, AB, Canada, 5GE Healthcare, Calgary, AB, Canada

This project evaluated the reliability of quantitative inhomogeneous magnetization transfer (qihMT), a novel myelin-sensitive measure, compared to more common measures, magnetization transfer ratio (MTR) and fractional anisotropy (FA), in 10 healthy adults.  A repeated measures ANOVA revealed no significant differences in measure means between scans in 18 white matter regions. Coefficients of variation (CV) demonstrated that FA had the highest reliability, followed by MTR and qihMT. The reduced reliability of qihMT observed here may be mitigated by further optimization of this novel sequence.

121
Pitch: 13:45
Poster: 14:45
Plasma 10
Remyelination is less efficient in periventricular white matter lesions in Multiple Sclerosis
Matteo Tonietto1, Emilie Poirion1, Caroline Papeix2, Michel Bottlaender3, Benedetta Bodini1,4, and Bruno Stankoff1,4

1ICM - Brain & Spine Institute, Paris, France, 2Neurology Department, Pitie-Salpetriere Hospital, Paris, France, 3IMIV, CEA, Inserm, CNRS, Univ. Paris-Sud, Université Paris Saclay, CEA-SHFJ, Paris, France, 4Neurology Department, St Antoine Hospital, Paris, France

The objective of this study was to investigate the relationship between the extent of spontaneous remyelination and the distance from ventricular cerebrospinal fluid (CSF) in a group of multiple sclerosis patients. Dynamic remyelination was measured using longitudinal [11C]PiB positron emission tomography and found to be significantly reduced in periventricular white matter lesions, while becoming progressively more extensive with increasing distance from ventricles. Moreover, we found a positive correlation between periventricular remyelination and cortical thickness. These results suggest that CSF-linked factors might interfere with the spontaneous remyelination process in multiple sclerosis patients.

122
Pitch: 13:45
Poster: 14:45
Plasma 11
Early life Myelination Mediates the Effects of the APOE Genotype on Cognitive Development
Justin Remer1,2,3, Douglas C. Dean4, Michaela Voyer2, and Sean C.L. Deoni2

1Neurosurgery, Westchester Medical Center, Valhalla, NY, United States, 2Pediatrics, Women and Infant's Hospital, Providence, RI, United States, 3Pediatrics, Brown University Warren Alpert School of Medicine, Providence, RI, United States, 4University of Wisconsin, Madison, WI, United States

A growing focus in Alzheimer’s Disease (AD) research is understanding the earliest preclinical structural changes associated with the disorder.  In prior studies our group has shown differences in early myelin content based on APOE genotype and we recently have shown preliminary results that APOE effects early longitudinal myelin and cognitive development.  Nevertheless, these results fail to explain how differences in early brain anatomy lead to differences in cognitive development.  This is the first study to explore and analyze if differences in early cognitive development based on APOE genotype is explained by differences in early myelin development in a large cohort of healthy neurotypical infants and young children stratified by presence or absence of at least one APOE ε4 allele.

123
Pitch: 13:45
Poster: 14:45
Plasma 12
Pitching the Cuprizone Mouse Model for Testing (re-) myelination therapies: robustness and reproducibility
Andreas Bruns1, Anna Mechling1, Eva Mracsko1, Thomas Mueggler1, and Basil Künnecke1

1Roche Pharma Research & Early Development, Neuroscience, Ophthalmology and Rare Diseases Discovery & Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland

We assessed robustness and reproducibility of the cuprizone mouse model of de- and remyelination for its use in testing novel pharmacological treatments of demyelinating disorders such as multiple sclerosis. In several multimodal MRI studies using independent batches of animals, increases in T2, decreases in MTR and FA and biphasic responses in MK upon cuprizone feeding, as well as partial recoveries after cuprizone withdrawal, showed huge effect sizes and high cross-study consistency, especially in the corpus callosum. Our results substantiate the suitability of the cuprizone mouse model for longitudinal monitoring of the pathology using multimodal MRI.

124
Pitch: 13:45
Poster: 14:45
Plasma 13
Multi-parameter quantitative MRI reveals common distribution of myelin in ex-vivo chimpanzee and in-vivo human brains
Daniel Papp1, Nicole Eichert1, Colin Reveley1, Stuart Clare1, and Rogier B Mars1,2

1Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 2Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, Netherlands

Post-mortem investigations of tissue properties can dramatically extend the biological information that can be obtained from bodies or tissue that cannot be easily investigated in-vivo, as is the case for the majority of species of interest to comparative neuroscience. Here, we show the potential of a quantitive MRI method, multi-parameter mapping, to obtain high-resolution information about tissue properties of large non-human primates that generally cannot be studied anatomically. We compare myelination indices, derived from ex-vivo chimpanzee data at 7T to those derived from in-vivo human data at 3T.

125
Pitch: 13:45
Poster: 14:45
Plasma 14
Effects of myelin on the water resonance line-shape in postmortem mouse brain
Sean Foxley1, Gregory S Karczmar1, Brian Popko2, Pedro Brugarolas3,4, Gregg Wildenberg5, Vandana Sampathkumar5, and Narayanan Kasthuri5

1Department of Radiology, University of Chicago, Chicago, IL, United States, 2Department of Neurology, University of Chicago, Chicago, IL, United States, 3Department of Radiology, Harvard Medical School, Boston, MA, United States, 4Gordon Center for Medical Imaging, Massachusetts General Hospital, Boston, MA, United States, 5Department of Neurobiology, University of Chicago, Chicago, IL, United States

Dysmyelinating diseases are characterized by abnormal myelin formation and function. Such microstructural abnormalities in myelin have been demonstrated to produce measurable effects on the MR signal. This work examines these effects from post-mortem fixed control and shiverer mouse brains on voxel-wise, high-resolution water spectra acquired using a multi-gradient echo pulse sequence. Results demonstrate that components of the spectra are differentially affected by myelin concentration. This suggests that water proton spectra may be sensitive to the tissue microenvironment, specifically myelin, and could serve as potential MRI based biomarkers of dysmyelinating diseases.

126
Pitch: 13:45
Poster: 14:45
Plasma 15
Quantitative multiparametric mapping assessment of the rat brain through adolescence into adulthood
Stephen Sawiak1,2, Bianca Jupp3, Jolyon A Jones3, Peter Zhukovsky3, and Jeffrey W Dalley3

1Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, United Kingdom, 2Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom, 3University of Cambridge, Cambridge, United Kingdom

We demonstrate high-resolution quantitative multiparametric mapping in the rat: scanning animals before and after adolescence and comparing them to the adult. We produce maps sensitive to myelin signal throughout the brain that complement volumetric information normally used in developmental studies. The aim is to better exploit models of neuropsychiatric disorders, particularly those with developmental components. 


Power Pitch

Pitch: MSK Power Pitch

Power Pitch Theater B - Exhibition Hall
Monday
Pitches: 13:45 - 14:45
Posters: 14:45 - 15:45
Moderators: Erin Englund & Dimitrios Karampinos
(no CME credit)
127
Pitch: 13:45
Poster: 14:45
Plasma 16
Multi-vendor multi-site T1ρ and T2 quantification of knee cartilage
Jeehun Kim1, Kenji Mamoto1, Richard Lartey1, Kaipin Xu1, Matthew Tanaka2, Emma Bahroos2, Carl S. Winalski1, Thomas M. Link2, Peter A. Hardy3, Qi Peng4, Angie Botto-van Bemden5, Kecheng Liu6, Robert D. Peters7, Can Wu8, and Xiaojuan Li1

1Program of Advanced Musculoskeletal Imaging (PAMI), Cleveland Clinic, Cleveland, OH, United States, 2University of California, San Francisco (UCSF), San Francisco, CA, United States, 3University of Kentucky, Lexington, KY, United States, 4Albert Einstein College of Medicine, Bronx, NY, United States, 5Arthritis Foundation, Atlanta, GA, United States, 6Siemens Medical Solution Inc, Malvern, PA, United States, 7GE Healthcare, Milwaukee, WI, United States, 8Philips Healthcare, Andover, MA, United States

T and T2 relaxation times are promising biomarkers for early detection of osteoarthritis due to its sensitivity to cartilage degeneration. Good reliability is essential for these quantitative measures to be widely applicable in clinical trials. We implemented MAPSS T and T2 imaging on multiple platforms (Siemens, GE, Philips) and evaluated the intra-site repeatability and inter-site reproducibility of T and T2 data in a multi-site multi-vendor setting. 

128
Pitch: 13:45
Poster: 14:45
Plasma 17
GagCEST at 3T Can Detect Cartilage Differences Between Healthy and OA Subjects
Elka Rubin1, Lauren Watkins2, Valentina Mazzoli1,3, Arjun D Desai1, Gabe Ho2, Feliks Kogan1, Scott Ulrich4, Julie Kolesar2, Scott Delp2,4,5, Gary Beaupre3, and Garry E Gold1,2

1Department of Radiology, Stanford University, Stanford, CA, United States, 2Department of Bioengineering, Stanford University, Stanford, CA, United States, 3Musculoskeletal Research Laboratory, VA Palo Alto Healthcare System, Palo Alto, CA, United States, 4Department of Mechanical Engineering, Stanford University, Stanford, CA, United States, 5Orthopaedic Surgery, Stanford, Stanford, CA, United States

Chemical exchange saturation transfer of GAG (gagCEST) is a quantitative MR technique that is a useful biomarker for assessing GAG content at 7T. However, its utility at 3T remains unclear. In this study, we compare gagCEST asymmetry values of healthy and osteoarthritic subjects scanned at 3T. Comparisons between healthy and OA subjects indicate a significant difference in the average gagCEST signal across the medial and lateral anterior and medial weight-bearing regions of the femoral cartilage. The results of this study suggest that there is potential for use of gagCEST in the study of OA at 3T.

129
Pitch: 13:45
Poster: 14:45
Plasma 18
Deep Learning Pipeline for Automated Identification of Osteoarthritic Degenerative Changes in the Hip
Eugene Ozhinsky1, Radhika Tibrewala1, Rutwik Shah1, Sarah C. Foreman1, Valentina Pedoia1, and Sharmila Majumdar1

1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States

Manual identification of bone and cartilage abnormalities in MR images can be laborious and time consuming. The goal of this study was to develop a fully automated deep learning pipeline to identify morphological and degenerative changes in patients with hip osteoarthritis (OA). It included an object detection deep convolutional neural network (DCNN) that generated cropped images of the hip joint and a classification DCNN that identified the presence of morphological bone and cartilage changes.

130
Pitch: 13:45
Poster: 14:45
Plasma 19
Added Clinical Value of Isotropic MAVRIC SL Acquisitions of Total Hip Arthroplasties
Kelly C. Zochowski1, Jacky Cheung1, Mauro A. Miranda1, Erin C. Argentieri1, Bin Lin1, S. Sivaram Kaushik2, Alissa J. Burge1, Matthew F. Koff1, and Hollis G. Potter1

1Hospital for Special Surgery, New York, NY, United States, 2MR Applications and Workflow, GE Healthcare, Waukesha, WI, United States

MAVRIC SL, a multi-spectral MRI imaging sequence, reduces metallic susceptibility artifact to improve visualization near joint arthroplasty by acquiring 24 spectral bins of off-resonance data.  Many implants require fewer bins, and this study uses a calibration scan to determine the number of bins necessary to permit an isotropic MAVRIC acquisition and a reduced TR isotropic MAVRIC acquisition.  The isotropic MAVRIC images decreased blurring and improved visualization of the periprosthetic bone and synovium while retaining image quality.  Lowering the TR decreased scan time but affected image interpretation. Isotropic MAVRIC acquisitions may improve the diagnostic capability of MAVRIC SL images.  

131
Pitch: 13:45
Poster: 14:45
Plasma 20
Five-minute single sequence comprehensive 4D pediatric ankle MRI with T2 Shuffling
Jonathan I Tamir1, Fida Wishah2, Jesse K Sandberg2, Marcus T Alley2, Michael Lustig1, and Shreyas S Vasanawala2

1Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, United States, 2Radiology, Stanford University, Stanford, CA, United States

The use of volumetric acquisitions for musculoskeletal MR in clinical settings has been limited due to blurring artifacts from T2 decay. T2 Shuffling (T2Sh), a redesigned 3D fast spin-echo technique that mitigates blurring, has been successfully applied to pediatric knee MRI in a clinical setting and used to streamline the pediatric knee exam. This work assesses a shortened T2Sh scan for pediatric ankle MRI with total scan time under 5 minutes. Our results show that T2Sh has the potential to provide a comprehensive diagnostic protocol in place of the conventional long 2D exam.

132
Pitch: 13:45
Poster: 14:45
Plasma 21
Denoising of Diffusion MRI Improves Peripheral Nerve Conspicuity and Reproducibility
Jaemin Shin1, Jahnavi Curlin2, Ek Tsoon Tan3, Maggie Fung1, and Darryl Sneag2

1GE Healthcare, New York, NY, United States, 2Hospital for Special Surgery, New York, NY, United States, 3GE Global Research, Niskayuna, NY, United States

This study evaluated q-space-based (genSD) and principal component analysis (PCA) denoising techniques to enhance SNR for peripheral nerve diffusion MRI of 10 healthy knees. The combination of both methods (PCA+genSD) was compared with a PCA-only method as well as the average of 10 repetitions. The combined denoising method showed improved performance with respect to SNR, peripheral nerve conspicuity and reproducibility.

133
Pitch: 13:45
Poster: 14:45
Plasma 22
Robust Motion-Compensated Lumbar Spine Bone imaging using 3D UTE with Broadband Inversion Recovery Pulse and k-space Weighted Navigator Gating
Masami Yoneyama1, Iain Ball2, Ben Kennedy3, Takayuki Sakai4, Atsuya Watanabe5,6, and Marc Van Cauteren7

1Philips Japan, Tokyo, Japan, 2Philips Australia & New Zealand, North Ryde, Australia, 3Qscan Radiology Clinics, Brisbane, Australia, 4Radiology, Eastern Chiba Medical Center, Chiba, Japan, 5General Medical Services, Chiba University Graduate School of Medicine, Chiba, Japan, 6Orthopaedic Surgery, Eastern Chiba Medical Center, Chiba, Japan, 7Philips Healthcare, Tokyo, Japan

We proposed a new technique for the lumbar spine MR bone imaging based on broadband inversion recovery prepared segmented multispoke UTE sequence with k-space weighted navigator gating (3D BoneVIEW) for assessment of low back pain. 3D BoneVIEW provided robust bone imaging with sufficient background suppression and without respiratory artifacts. This sequence has a great potential to help more accurate assessment of the low back pain as an alternative to CT imaging.

134
Pitch: 13:45
Poster: 14:45
Plasma 23
Self-navigated, rapid 3D UTE for motion-robust skull imaging
Hyunyeol Lee1, Xia Zhao1, Hee Kwon Song1, Rosaline Zhang2, Scott P Barttlett2, and Felix W Wehrli1

1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Plastic Surgery, University of Pennsylvania, Philadelphia, PA, United States

Solid-state MRI via 3D UTE or ZTE methods has potential for bone-selective imaging as a radiation-free alternative to computed tomography, particularly for children with craniofacial abnormalities. However, relatively long scan times make the technique vulnerable to artifacts from involuntary subject movements, thereby impairing image quality. Here, we developed a self-navigated, rapid 3D UTE technique by combining a retrospective motion detection and correction approach with sparsity-constrained image reconstruction. Results from in vivo studies demonstrate the proposed method's feasibility in achieving motion-corrected whole-skull images at 1 mm isotropic resolution in 2.1 minutes scan time.

135
Pitch: 13:45
Poster: 14:45
Plasma 24
Fat Suppression in UTE Imaging of Short T2 Tissues Using a Novel Soft-hard Composite RF Pulse
Ya-Jun Ma1, Saeed Jerban1, Hyungseok jang1, Eric Y Chang1,2, and Jiang Du1

1Radiology, University of California, San Diego, San Diego, CA, United States, 2VA San Diego Healthcare System, San Diego, CA, United States

Fat suppression is very important for both high contrast morphological imaging and accurate quantitative MR imaging. However, the conventional fat suppression methods such as chemical shift-based fat saturation are not well-suited for short T2 imaging due to the large direct saturation of short T2 tissues with broad spectra. The purpose of this study was to design a novel fat suppression pulse for ultrashort echo time (UTE) imaging of short T2 tissues with well-preserved short T2 signals using a soft-hard composite pulse.

136
Pitch: 13:45
Poster: 14:45
Plasma 25
Cortical bone quantifications using ultrashort echo time MR imaging (UTE-MRI) correlate well with histomorphometric assessment of bone microstructure
Saeed Jerban1, Yajun Ma1, Jonathan H Wong2, Amin Nazaran1, Adam Searleman1, Lidi Wan1, Judith Williams2, Eric Y Chang1,2, and Jiang Du1

1Radiology, University of california, San Diego, San Diego, CA, United States, 2Radiology Service, VA San Diego Healthcare System, San Diego, CA, United States

Ultrashort echo time magnetic resonance imaging (UTE-MRI) has been used to assess cortical bone porosity, as validated routinely with high resolution micro computed tomography (μCT). This study investigated the correlations between UTE-MRI-based quantifications and histomorphometric measures, as well as between UTE-MRI-based quantifications and μCT results. MRI properties showed strong correlations with both histomorphometric and μCT-based porosities. Only UTE-MRI could assess small pore (<40 μm) variations with moderate correlations. Major porosity changes were from large pores in studied specimens; therefore, μCT employment is likely adequate to validate UTE-MRI biomarkers. However, UTE-MRI techniques can assess pores below the detectable range by μCT, porosities which might contribute differently to bone mechanics.

137
Pitch: 13:45
Poster: 14:45
Plasma 26
A Quantitative, Multiparametric Method for Bone Edema and Adiposity Characterisation in Inflamed Trabecular Bone
Timothy JP Bray1, Naomi S Sakai1, Alexandra Dudek1, Kannan Rajesparan1, Corinne Fisher2, Coziana Ciurtin2, Debajit Sen2, Alan Bainbridge3, and Margaret A Hall-Craggs1

1Centre for Medical Imaging, University College London, London, United Kingdom, 2Arthritis Research UK Centre for Adolescent Rheumatology, University College London, London, United Kingdom, 3Magnetic Resonance Imaging Physics, University College London Hospitals, London, United Kingdom

MRI is increasingly used to identify and monitor inflammation in patients with inflammatory diseases involving the skeleton, such as spondyloarthritis. However, conventional image interpretation by radiologists provides only indirect information about the inflammatory process and lacks reproducibility. Here, we describe a partially-automated multiparametric MRI tool for quantifying and characterising both active and chronic inflammation in spondyloarthritis, relying on histographic analysis of apparent diffusion coefficient (ADC) and proton density fat fraction (PDFF) maps. We show that histographic analysis improves performance compared to simple averaging, and, further, that ADC and PDFF provide distinct, complementary information regarding active inflammation and structural damage respectively. 

138
Pitch: 13:45
Poster: 14:45
Plasma 27
Texture analysis based on diffusional kurtosis imaging for the differentiation of benign and malignant bone tumors
Ying Li1, Cuiping Ren1, Jingliang Cheng1, and Zhizheng Zhuo2

1First affiliated hospital of Zhengzhou university, Zhengzhou, China, 2Clinical Science, Philips Healthcare, Beijing, China

This work investigated and evaluated the role of textures extracted from magnetic resonance (MR) diffusion kurtosis imaging (DKI) in characterizing the bone tumors, and furtherly evaluate the ability of these textures to differentiate benign and malignant tumors by using support vector machine classifiers (SVM), which might be helpful for clinical diagnosis and studies. The texture parameters have the ability to character the bone tumor and SVM classifier showed good performance in the differentiation of benign and malignant bone tumors.  

139
Pitch: 13:45
Poster: 14:45
Plasma 28
Pilot study on facioscapulohumeral muscular dystrophy patients with dynamic phase contrast imaging of electrically stimulated quadriceps muscles
Xeni Deligianni1,2, Francesco Santini1,2, Giorgio Tasca3, Mauro Monforte3, Francesca Solazzo4, Raimondo Vitale5, Paolo Felisaz6, Giancarlo Germani4, Niels Bergsland4, Enzo Ricci3, and Anna Pichiecchio4

1Department of Radiology/Division of Radiological Physics, University Hospital Basel, Basel, Switzerland, 2Department of Biomedical Engineering, University of Basel, Basel, Switzerland, 3Unità Operativa Complessa di Neurologia, Dipartimento di Scienze dell’Invecchiamento, Neurologiche, Ortopediche e della Testa-Collo, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy, 4Neuroradiology Department, IRCCS Mondino Foundation, Pavia, Italy, 5University of Pavia, Pavia, Switzerland, 6Radiology Department, Desio Hospital ASST, Monza, Italy

Facioscapulohumeral muscular dystrophy is characterized by a peculiar non-linear muscle-by-muscle involvement and is very hard to predict. The purpose of this study was to use dynamic phase contrast MR imaging of electrically stimulated quadriceps muscle to characterize the elastic potential of the muscle in FSHD patients and contribute to the understanding of this challenging disease. Velocity, strain, and strain rate were analyzed and compared to the results of physical examination.

140
Pitch: 13:45
Poster: 14:45
Plasma 29
Quantitative MRI Measurements can Distinguish Myositis From Healthy Control Muscle.
Matthew Farrow1,2, Ai Lyn Tan1,2, Paul Emery1,2, Maya Buch1,2, Andrew Grainger1,2, Steven Tanner2, and John Biglands2

1Leeds Institute of Rheumatic and Musculoskeletal Medicine, Leeds, United Kingdom, 2NIHR Leeds Biomedical Research Centre, Leeds, United Kingdom

Myositis is an autoimmune inflammatory muscle disease which can decrease quality of life and increase mortality. Clinical presentation includes muscle weakness, changes in muscle microstructure, myosteatosis and myalgia. Current diagnosis is reliant on subjective clinical examinations, blood tests and invasive biopsies. Quantitative MRI techniques such as diffusion and fat fraction measurements are sensitive to changes within the muscle. 10 myositis patients and 16 healthy controls underwent scans of the thigh. Significant differences were found in fat fraction and diffusion measurements between myositis patients and healthy controls, implying these measures have potential as biomarkers in the diagnosis and management of myositis.

141
Pitch: 13:45
Poster: 14:45
Plasma 30
Imaging of calf muscle contraction in pediatric patients with cerebral palsy and healthy children by dynamic phase contrast MRI
Claudia Weidensteiner1,2, Xeni Deligianni1,2, Francesco Santini1,2, Tanja Haas1, Philipp Madoerin1, Oliver Bieri1,2, Katrin Bracht-Schweizer3, Erich Rutz4, Meritxell Garcia5, and Reinald Brunner4

1Department of Radiology, Division of Radiological Physics, University of Basel Hospital, Basel, Switzerland, 2Department of Biomedical Engineering, University of Basel, Basel, Switzerland, 3Laboratory for Movement Analysis, University Children's Hospital Basel, Basel, Switzerland, 4Department of Orthopedic Surgery, University Children's Hospital Basel, Basel, Switzerland, 5Department of Radiology, Division of Neuroadiological Physics, University of Basel Hospital, Basel, Switzerland

Aim of this study is to investigate the feasibility of phase contrast imaging for assessment of muscle function in children with cerebral palsy (CP). Time-resolved cine phase contrast MRI was synchronized with electrical muscle stimulation of the calf muscle at a clinical 3T MRI scanner.  11 healthy and 4 children with hemiparetic CP were scanned. Dynamic velocity, strain, and strain rate maps were reconstructed. Synchronous dynamic PC MRI of electrically stimulated muscle is feasible in children, even in CP patients and might provide further insight into the health status of their muscles.


Power Pitch

Pitch: Cutting Edge CEST

Power Pitch Theater C - Exhibition Hall
Monday
Pitches: 13:45 - 14:45
Posters: 14:45 - 15:45
Moderators: Ricardo Martinho & Renhua Wu
(no CME credit)
142
Pitch: 13:45
Poster: 14:45
Plasma 31
Accelerate Parallel CEST Imaging with Dynamic Convolutional Recurrent Neural Network
Huajun She1, Quan Chen1, Shuo Li1, Kang Yan1, Xudong Chen1, Xi Chen1, Yuan Feng1, Jochen Keupp2, Robert Lenkinski3,4, Elena Vinogradov3,4, and Yiping P. Du1

1Institute for Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China, 2Philips Research, Hamburg, Germany, 3Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, 4Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States

CEST is a new contrast mechanism in MRI. However, a successful application of CEST is hampered by its slow acquisition. This work investigates accelerating parallel CEST imaging using dynamic convolutional recurrent neural networks. This work is the first try to apply recurrent neural networks to accelerate CEST imaging, which jointly learns the spatial and Z-spectral features. The in vivo brain results show that the proposed method demonstrates a much better reconstruction quality of the human brain MTRasym maps than the traditional dynamic compressed sensing method, while the reconstruction time is one hundred times shorter.

143
Pitch: 13:45
Poster: 14:45
Plasma 32
Denoising of Z-spectra for stable CEST MRI using principal component analysis
Johannes Breitling1,2,3, Anagha Deshmane4, Steffen Goerke1, Kai Herz4, Mark E. Ladd1,2,5, Klaus Scheffler4,6, Peter Bachert1,2, and Moritz Zaiss4

1Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany, 3Max Max Planck Institute for Nuclear Physics, Heidelberg, Germany, 4High-field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 5Faculty of Medicine, University of Heidelberg, Heidelberg, Germany, 6Department of Biomedical Magnetic Resonance, Eberhard-Karls University Tübingen, Tübingen, Germany

Chemical exchange saturation transfer (CEST) MRI allows for the indirect detection of low-concentration biomolecules by their saturation transfer to the abundant water pool. However, reliable quantification of CEST effects remains challenging and requires a high image signal-to-noise ratio.  In this study, we show that principle component analysis can provide a denoising capability which is comparable or better than 6-fold averaging. Principle component analysis allows identifying similarities across all noisy Z-spectra, and thus, extracting the relevant information. The resulting denoised Z-spectra provide a more stable basis for quantification of selective CEST effects, without requiring additional measurements.

144
Pitch: 13:45
Poster: 14:45
Plasma 33
Homogenous Excitation in Whole Brain CEST: Combination of Snapshot CEST and Multiple Interleaved Mode Saturation
Andrzej Liebert1, Moritz Zaiss2, Rene Gumbrecht3, Patrick Liebig3, Benjamin Schmitt3, Frederik Laun1, Arnd Doerfler4, Michael Uder1, and Armin M. Nagel1

1Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany, 2Max Planck Institute for Biological Cybernetics, Tuebingen, Germany, 3Siemens Healthcare GmbH, Erlangen, Germany, 4Department of Neuroradiolohy, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany

To perform Chemical Exchange Saturation Transfer MRI of the whole brain a homogeneous saturation and fast readout are required. To achieve a fast and robust 3D acquisition a spiral-centric-reordered GRE readout was used. In addition, a Multiple Interleaved Mode Saturation scheme was applied to mitigate B1+-inhomogeneity effects of the CEST saturation. Combination of these two methods allows acquiring a homogenous CEST contrast in a volume of approximately 220x220x45mm3 within an acquisition time of 7 min 26s.

145
Pitch: 13:45
Poster: 14:45
Plasma 34
A Novel Approach for Improved CEST Imaging with Real-Time Frequency Drift Correction
Ruibin Liu1, Hongxi Zhang2, Weiming Niu2, Can Lai2, Qiuping Ding1, Weibo Chen3, Sayuan Liang4, Jinyuan Zhou5, Dan Wu1,5, and Yi Zhang1,5

1Key Laboratory for Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China, 2Department of Radiology, Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China, 3Philips Healthcare, Shanghai, China, 4Clinical Research Board, Philips Research China, Shanghai, China, 5Department of Radiology, Johns Hopkins University, Baltimore, MD, United States

Chemical Exchange Saturation Transfer (CEST) imaging is highly sensitive to temporal B0 drift. Here, we proposed a novel frequency-stabilized CEST (FS-CEST) imaging sequence by adding a frequency stabilization module to the conventional non-frequency-stabilized CEST (NFS-CEST) sequence for correcting artifacts due to B0 drift in real time. The FS-CEST sequence was implemented in phantoms and 26 human volunteers, and generated substantially more stable magnetization transfer ratio asymmetry (MTRasym) spectra and amide proton transfer weighted (APTw) images than the conventional NFS-CEST sequence. The FS-CEST sequence provides an effective approach for B0 drift correction without additional scan time.

146
Pitch: 13:45
Poster: 14:45
Plasma 35
Z-Spectral Water-Fat Separation for APTw MRI in the Body using efficient Single-Echo Acquisitions
Jochen Keupp1, Elena Vinogradov2, and Holger Eggers1

1Philips Research, Hamburg, Germany, 2University of Texas Southwestern Medical Center, Dallas, TX, United States

An APTw/CEST-MRI technique to obtain water-only Z-spectra in the presence of fat is described. Water-fat separation in CEST is complicated by partial saturation of spectral fat components. Here, the saturation frequency-dependent water-fat phases are calculated using a multi-peak saturation model. A Z-spectrum acquisition with a single echo-shift is combined with a reference acquisition (S0) using 3 echo-shifts for water-fraction and B0-mapping. A B0-corrected, water-only Z-spectrum is obtained by complex rotations and weighted subtraction according to the water-fat phase. Volunteer examinations at 3T are shown (breast and abdominal). The single echo-shift technique offers a time-efficient means for water-fat separation in APTw/CEST-MRI.

147
Pitch: 13:45
Poster: 14:45
Plasma 36
Amide proton transfer (APT) imaging of uterine cervical cancer; prediction of histological findings
Keisuke Ishimatsu1, Akihiro Nishie1, Yukihisa Takayama1, Yoshiki Asayama1, Yasuhiro Ushijima1, Daisuke Kakihara1, Tomohiro Nakayama1, Koichiro Morita1, Seiichiro Takao1, Osamu Togao1, Yoshihiro Ohishi2, Kenzo Sonoda3, Jochen Keupp4, and Hiroshi Honda1

1Department of Clinical Radiology, Kyushu university, Fukuoka, Japan, 2Department of Anatomic Pathology, Kyushu university, Fukuoka, Japan, 3Department of Obstetrics and Gynecology, Kyushu university, Fukuoka, Japan, 4Philips Research, Hamburg, Germany

It is important to diagnose histological type and existence of parametrial invasion in uterine cervical cancer as correctly as possible because these factors are important in choosing treatment strategies or predicting prognosis. The objective of our study is to investigate whether amide proton transfer (APT) imaging is useful for evaluation of uterine cervical cancer. We compared the APT signal of uterine cervical cancer with different histological findings (histological type and existence of parametrial invasion) using three different durations of presaturation pulse.

148
Pitch: 13:45
Poster: 14:45
Plasma 37
Fat corrected APT-CEST in the human breast at 7 Tesla: application to mamma carcinoma and dependency on menstrual cycle
Ferdinand Zimmermann1,2, Andreas Korzowski1, Lisa Carmen Loi3, Johannes Sebastian Breitling1,2,4, Jan-Eric Meissner1, Moritz Zaiss5, Sebastian Bickelhaupt3, Heinz-Peter Schlemmer3, Mark E. Ladd1, Peter Bachert1,2, Daniel Paech3, Sarah Schott6, and Steffen Goerke1

1Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Department of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany, 3Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 4Max Planck Institute for Nuclear Physics, Heidelberg, Germany, 5High‐field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 6Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany

The fat correction method enables robust APT-CEST quantification in the human breast and proved its suitability for examinations in vivo. We present to the extent of our knowledge the first APT-CEST contrast corrected for fat signal contribution, spillover, B1 field inhomogeneities and T1 relaxation in a breast cancer patient. The CEST contrast increased threefold compared to the measurement of a healthy volunteer. Repeated CEST imaging over the course of one menstrual cycle in one healthy woman did not reveal a hormonal correlation of APT contrast. A clinical study in healthy premenopausal volunteers will now investigate the dependency on menstrual cycle.

149
Pitch: 13:45
Poster: 14:45
Plasma 38
NaSA-CEST MRI: comparison with Gd-enhanced contrast for imaging brain inflammation
Xiaolei Song1,2, Yanrong Chen1,3, Chenwang Jin1,2, Tao Liu1,2, Chengyan Chu1,2, Yuguo Li1, Yue Yuan1,2, Xiaowei He3, Piotr Walczak1,2, and Jeff WM Bulte1,2

1Russell H. Morgan Dept. of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States, 2Cellular Imaging Section, Institute for Cell Engineering, Johns Hopkins University, Baltimore, MD, United States, 3Dept. of Information Sciences and Technology, Northwest University, Xi'an, China

Sodium salicylate (NaSA), a nonsteroidal anti-inflammatory drug and the main metabolite of aspirin, accumulates specifically in inflamed tissue. Since NaSA can be detected with CEST-MRI at millimolar concentrations, we investigated the use of NaSA-enhanced CEST MRI for in vivo mapping of brain inflammation, induced by intracerebral injection of lipopolysaccharide in mice. NaSA-CEST shows signal enhancement in the inflamed LPS-injected hemisphere, which was not observed in two control groups. NaSA-CEST exhibits distinct signal kinetics and enhanced regions from that of Gd-enhanced MRI, and shows correlations with histological staining of inflammatory markers, indicating its potential as a new platform for imaging neuroinflammation.

150
Pitch: 13:45
Poster: 14:45
Plasma 39
Proton exchange rate increases in MS lesions
Mehran Shaghaghi1, Weiwei Chen2, Alessandro Scotti3,4, Haiqi Ye5, Yan Zhang5, Wenzhen Zhu2, and Kejia Cai3,6

1Radiology, University of Illinois, Chicago, IL, United States, 2Department of Radiology, Huazhong University of Science & Technology, China, China, 3Radiology, University of Illinois at Chicago, Chicago, IL, United States, 4Bioengieering, University of Illinois at Chicago, Chicago, IL, United States, 5Huazhong University of Science & Technology, Wuhan, China, 6Bioenginnering, University of Illinois at Chicago, Chicago, IL, United States

We have evaluated the performance of magnetic resonance proton exchange (Kex) imaging in vivo in characterization of gray matter, white matter as well as MS lesions. With informed consent, 10 control and 8 MS diagnosed subjects underwent a brain MRI on a 3T clinical-scanner.  Kex maps were generated by pixel-wise fitting of the omega plot constructed from four different saturation power (B1=1, 2, 3 & 4 µT).  Kex values from gray matter (GM), white matter (WM) and lesions were calculated, and two-tailed paired Student’s T-test was used to classify each group. Kex was able to demarcates each region. The combined use of Kex mapping has potential to improve the early and specific diagnosis of MS. 

151
Pitch: 13:45
Poster: 14:45
Plasma 40
Multicolor metabolic quantitative CEST (mmqCEST): high resolution imaging of brain metabolites
Vitaliy Khlebnikov1, Alex Bhogal1, Mark Schuppert2, Moritz Zaiss2, Tobias Lindig3, Benjamin Bender3, Ulrike Ernemann3, Klaus Scheffler2,4, Peter Luijten1, Hans Hoogduin1, Dennis Klomp1, and Jeanine J Prompers1

1University Medical Center Utrecht, Utrecht, Netherlands, 2Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 3Eberhard-Karls University, Tübingen, Germany, 4Eberhard-Karls University Tübingen, Tübingen, Germany

Multicolor metabolic quantitative CEST (mmqCEST): high resolution imaging of brain metabolites

152
Pitch: 13:45
Poster: 14:45
Plasma 41
150× acceleration of myelin water imaging data analysis by a neural network
Hanwen Liu1,2, Qing-san Xiang1,3, Roger Tam3,4, Alex L. MacKay1,3, John K. Kramer2,5, and Cornelia Laule1,2,3,6

1Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada, 2International Collaboration on Repair Discoveries, Vancouver, BC, Canada, 3Radiology, University of British Columbia, Vancouver, BC, Canada, 4Biomedical Engineering, University of British Columbia, Vancouver, BC, Canada, 5Kinesiology, University of British Columbia, Vancouver, BC, Canada, 6Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada

In-vivo information of myelin content is desirable for studying many brain diseases and injuries which damage myelin. Myelin water imaging (MWI) is a validated and quantitative MR method to myelin. However, the data post-processing of MWI is mathematically complex and computationally demanding. The analysis typically takes several hours for a whole brain analysis, which limits its clinical applications. Our objective was to train a neural network as an alternative method for the MWI data analysis. We found this novel approach can accelerate MWI data analysis by over 150 times.

153
Pitch: 13:45
Poster: 14:45
Plasma 42
Contrasting frequency shifts and QSM in a longitudinal analysis of MS lesions to determine the nature of MR frequency and QSM signal changes
Vanessa Wiggermann1,2,3, Enedino Hernandez-Torres2,3, Irene M Vavasour3,4, Cornelia Laule1,5,6, David KB Li4,7, Anthony Traboulsee7, Alexander MacKay1,3,4, and Alexander Rauscher1,2,4

1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2Pediatrics, University of British Columbia, Vancouver, BC, Canada, 3UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada, 4Radiology, University of British Columbia, Vancouver, BC, Canada, 5Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada, 6International Collaboration on Repair Discoveries (ICORD), Vancouver, BC, Canada, 7Medicine (Neurology), University of British Columbia, Vancouver, BC, Canada

Magnetic susceptibility and MR frequency shifts in MS lesions are sensitive measures of tissue damage. However, the sensitivity of FS and QSM to magnetic susceptibility effects as well as changes in tissue microarchitecture complicate data interpretation in biological systems. By contrasting QSM and resonance frequency shift maps these two mechanisms may be differentiated. We observed that the signal shifts at enhancement are reflective of microstructural changes indicating formation of myelin debris, as similar FS and QSM changes were observed. Signal reductions in MS lesions 5yrs-post-enhancement however are only present on QSM, suggesting removal of myelin debris and axonal loss as the underlying mechanisms.

154
Pitch: 13:45
Poster: 14:45
Plasma 43
Impact of unilateral carotid artery stenosis on white matter fiber orientation effects of mq-BOLD derived oxygen extraction fraction
Stephan Kaczmarz1,2, Jens Goettler1,2,3, Andreas Hock4, Claus Zimmer1, Fahmeed Hyder2, and Christine Preibisch1,5

1Department of Neuroradiology, Technical University of Munich, Munich, Germany, 2MRRC, Yale University, New Haven, CT, United States, 3Clinic for Radiology, Technical University of Munich, Munich, Germany, 4Philips Healthcare, Hamburg, Germany, 5Clinic for Neurology, Technical University of Munich, Munich, Germany

Assessment of relative oxygen extraction fraction (rOEF) in white matter (WM) by multiparametric quantitative-BOLD (mq-BOLD) has highest clinical relevance, but was so far limited due to known WM anisotropy effects. Here, we present data from a clinical study in 29 internal carotid artery stenosis (ICAS) patients and 30 age-matched healthy controls (HC). The major aim was to characterise the ICAS impact on T2*, T2, R2’, rCBV and rOEF orientation dependencies in WM. Our results show very similar rOEF orientation dependencies for ICAS-patients compared to HC and low average rOEF orientation errors of 4.5% indicating potentially meaningful rOEF evaluations in WM.

155
Pitch: 13:45
Poster: 14:45
Plasma 44
Quantitative assessment of the degeneration of the superior cerebellar peduncle in Friedreich’s ataxia at 7 T: susceptibility, diffusion anisotropy, and T2 and T1 relaxometry
Sina Straub1, Julian Emmerich1,2, Stephanie Mangesius3, Elisabetta Indelicato4, Mark E. Ladd1,2,5, Sylvia Boesch4, and Elke R. Gizewski3

1Division of Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany, 2Faculty of Physics and Astronomy, Heidelberg University, Heidelberg, Germany, 3Department of Neuroradiology, Medical University Innsbruck, Innsbruck, Austria, 4Department of Neurology, Medical University Innsbruck, Innsbruck, Austria, 5Faculty of Medicine, Heidelberg University, Heidelberg, Germany

Friedreich’s ataxia is a rare disease involving degenerative processes within white matter fiber tracts, spinal nerves and the cerebellum. A correlation of patients’ clinical status and superior cerebellar peduncle atrophy has been shown in MR volumetry studies. The ongoing ultra-high field study presented here assesses the degeneration of the superior cerebellar peduncle in Friedreich’s ataxia with quantitative MR parameters – susceptibility, diffusion anisotropy, and T2 and T1 relaxometry. Statistically significant differences between fractional anisotropy as well as T2 values in patients and healthy controls could be observed, indicating that these quantitative MRI methods potentially provide valuable biomarkers to assess the course of Friedreich’s ataxia.

156
Pitch: 13:45
Poster: 14:45
Plasma 45
Glucose Uptake in Mouse Brain Detected by MRI Frequency Shifts with a Jump-Return Sequence
Zhiliang Wei1,2, Haifeng Zeng1,2, Lin Chen1,2, Kannie Chan1,2,3, Xiang Xu1,2, Issel Anne Lim1,2, Xu Li1,2, Hanzhang Lu1,2, Peter C.M. van Zijl1,2, and Jiadi Xu1,2

1Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, Baltimore, MD, United States, 2F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, United States, 3Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China

Neuronal activity relies on glucose metabolism for energy maintenance and abnormalities in glucose uptake and metabolism constitute a potential biomarker for many disorders, including neurodegenerative diseases. Existing MRI techniques for monitoring glucose uptake and transportation often suffer from insufficient detection sensitivity. Here, we demonstrate a jump-return MRI (JR-MRI) method with high sensitivity for monitoring glucose uptake via tracing the water-frequency shift induced by chemical exchange. Conventional MRS was performed to validate the delivery of glucose to the brain.


Combined Educational & Scientific Session

Mapping the Liver

Organizers: Utaroh Motosugi, Mustafa Shadi Bashir
Room 510A-D
Monday 13:45 - 15:45
Moderators: Bachir Taouli & Scott Reeder
13:45
Technical Development
Diego Hernando1

1University of Wisconsin-Madison, Madison, WI, United States

This presentation will describe MRI-based techniques for quantification of fat and iron deposition in the liver. Specifically, this presentation will cover: 1) the relevant MR contrast mechanisms related to the presence of fat and iron, 2) the types of pulse sequences used to probe these contrast mechanisms, 3) the main challenges for quantification of fat and iron, 4) the technical solutions to these challenges, and 5) the state of the art of development and validation of MRI-based techniques for quantification of fat and iron deposition in the liver.  

14:15
Clinical Applications
Jeong Min Lee1

1Seoul National University

New advances in liver MRI including T1-,T2*- and T1 rho mapping techniques, proton density fat fraction (PDFF) and elastography techniques may enable diagnosis of unseen pathologies by conventional techniques in the liver.  In addition, Gd-EOB-DTPA can enable assessment of liver function by using postcontrast hepatobiliary phase or T1 reduction rate (normally above 60%). In the near future, MR fingerprinting may enable single slice acquisition and easy implementation of multiparametric MRI and follow-up of patients. These noninvasive imaging techniques serve an alternative or complimentary role to invasive liver biopsy. Mapping techniques of the liver, for fat, iron, and fibrosis quantitative imaging is increasingly being used in clinical practice, and may soon become standard of care. 

157
14:45
Evaluating the clinical efficacy of magnetic resonance elastography in patients with Budd-Chiari syndrome
Peng Xu1, Kai Xu1, Weiqiang Dou2, and Yong Shen3

1Affiliated Hospital of Xuzhou Medical University, Xuzhou, China, 2GE Healthcare, MR Research China, Beijing, China, 3GE Healthcare, MR Enhanced Application China, Beijing, China

Budd-Chiari syndrome (BCS) is a rare disorder with an obstruction of the hepatic venous outflow tract.  Previous studies reported that liver stiffness (LS) was associated with liver function in some chronic liver diseases. In this study, magnetic resonance elastography was for the first time applied to investigate the LS levels of BCS patients staged with different Child-Pugh grades. As a result, significant correlation between LS levels and liver function properties was shown in BCS patients. In addition, higher LS levels were found in BCS patients with higher grades and lower LS levels were observed for patients after receiving treatment. 

158
14:57
Quantification and Repeatability of the Collagen Signal Fraction in the Healthy Liver Using Ultrashort Echo Time (UTE) MRI
Adrienne G. Siu1, Ferenc E. Mózes1, Luca Biasiolli1, and Matthew D. Robson1

1Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom

Liver injury can lead to fibrosis, i.e. an accumulation of collagen. Fibrosis is clinically assessed via biopsy. Due to the health risks and unrepresentative sampling associated with biopsy, a non-invasive method of quantifying collagen would be beneficial. Here, an ultrashort echo time (UTE) pulse sequence was employed to quantify the collagen signal fraction in 10 subjects with healthy livers in a test-retest study at 3 T. The collagen signal fraction was repeatable, with a mean of 14 ± 3 %.

159
15:09
Feasibility Study of MRI IDEAL-IQ Sequence in Evaluating Liver Function of Patients with Liver Cirrhosis
Nan Wang1, Ailian Liu1, Qinhe Zhang1, and Lizhi Xie2

1The First Affiliated Hospital of Dalian Medical University, Dalian, China, 2GE Healthcare, BeiJing, China

Liver biopsy is the gold standard for the diagnosis of liver cirrhosis, but because the biopsy is invasive, and liver tissue sampling is insufficient and sampling error (puncture location) exists. IDEAL-IQ sequence can be used to analyze liver fat fraction and iron content (R2*) simultaneously, and it is easy to operate.

160
15:21
Can Intravoxel Incoherent Motion Diffusion-weighted Imaging Be used for Preoperative Assessment of Microvascular Invasion in Hepatocellular Carcinoma ?
Yi Wei1, Hehan Tang1, Xiaocheng Wei2, and Bin Song1

1West China Hospital, Sichuan University, Chengdu, China, 2GE Healthcare China, MR Research, Beijing, China

Microvascular invasion (MVI) is one of the most important factors for the recurrence of hepatocellular carcinoma (HCC), however, accurate preoperative evaluation of MVI is quietly difficult because of the controversy results caused by the conventional imaging features. Compared with diffusion-weighted imaging (DWI), Intravoxel incoherent motion (IVIM) diffusion-weighted MR imaging could better characterize heterogeneity and irregularity of tissue components, and thus may have the potential to better evaluate MVI. In this study, we prospectively determine the usefulness of IVIM parameters and conventional radiologic features for preoperative prediction of MVI in patients with HCC.

161
15:33
In vivo mapping of liver microstructure using quantitative Temporal Diffusion Spectroscopy Imaging
Xiaoyu Jiang1, Junzhong Xu1, and John Gore1

1Vanderbilt University Institute of Imaging Science, nashville, TN, United States

Architectural and morphological changes of hepatocytes (the major parenchymal cells carrying out most of the metabolic functions of the liver) are key diagnostic findings for liver diseases and are associated with important biological events. However, such information can currently only be assessed by liver biopsy. Quantitative temporal diffusion spectroscopy imaging (qTDSI), which uses different modulated gradient waveforms to measure ADC values equivalent to the use of multiple diffusion times (Δ), has been shown to provide accurate, high-resolution maps of cell size in solid tumors. In this study, we demonstrated that qTDSI can map hepatocyte sizes in mice in vivo.

15:45
Adjournment


Oral

Fiber Orientations & Tractography

Room 511BCEF
Monday 13:45 - 15:45
Moderators: Fulvia Palesi
162
13:45
Mapping of fibre-specific relaxation and diffusivities in heterogeneous brain tissue
João P. de Almeida Martins1,2, Chantal M. W. Tax3, Sarah E. Mailhiot1, Filip Szczepankiewicz2,4,5, Maxime Chamberland3, Carl-Fredrik Westin4,5, Derek K. Jones3, and Daniel Topgaard1,2

1Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden, 2Random Walk Imaging AB, Lund, Sweden, 3Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom, 4Harvard Medical School, Boston, MA, United States, 5Radiology, Brigham and Women’s Hospital, Boston, MA, United States

While diffusion MRI tractography has provided important insights on the human brain connectome, fibre-tracking through heterogeneous voxels has proven to be a challenging endeavour. Recently, we devised MRI acquisition- and processing methods to resolve sub-voxel heterogeneity with nonparametric 5D relaxation-diffusion distributions where contributions from distinct tissues are separated while circumventing the use of limiting assumptions. The separation between tissue-signals provides a clean mapping of nerve fibres that can then be used as an input in fibre-tracking algorithms. Additionally, values of relaxation rates and diffusivities are estimated for each distinct fibre bundle, potentially giving tract-specific information on chemical composition and microstructure.

163
13:57
Estimation of multiple fiber orientation distributions (mFODs) from diffusion MRI data using spherical deconvolution
Alberto De Luca1, Fenghua Guo1, and Alexander Leemans1

1Image Sciences Institute, UMC Utrecht, Utrecht, Netherlands

Fiber orientation distributions (FODs) of white matter (WM) are commonly estimated from brain diffusion MRI data with spherical deconvolution (SD) approaches. Typically, only WM is considered to be anisotropic in SD, relying on suboptimal isotropic modeling of grey matter (GM). Here we present a general framework to reconstruct multiple anisotropic FODs (mFODs) from multiple response functions, allowing for the investigation of anisotropy in GM. The estimated mFODs were evaluated on a dataset from the HCP project with five response functions generated with the diffusion kurtosis and NODDI approaches, and their performances compared to state-of-the-art SD approaches.

164
14:09
Diffusion MRI in the unfolded hippocampus
Uzair Hussain1, Jordan DeKraker1,2,3, Corey A. Baron1,2,4,5, and Ali R. Khan1,2,4,5

1Centre for Functional and Metabolic Mapping, Robarts Research Institute, Western University, London, ON, Canada, 2Neuroscience Graduate Program, Western University, London, ON, Canada, 3The Brain and Mind Institute, Western University, London, ON, Canada, 4Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, 5School of Biomedical Engineering, Western University, London, ON, Canada

The hippocampus is of high interest to the research community due to its involvement in many neurological disorders. However, in-vivo imaging, particularly diffusion weighted imaging, is challenging due to the hippocampus’ complicated curved geometry and small size. We address these challenges with an approach that ‘unfolds’ the hippocampus into a thin sheet. This allows migration of the diffusion data into this unfolded hippocampus, which enables visualization of microstructural sensitive diffusion  parameters in a space where hippocampal subfields can be readily distinguished.

165
14:21
Towards validation of diffusion MRI tractography: bridging the resolution gap with 3D Polarized Light Imaging
Abib O. Y Alimi1, Samuel Deslauriers-Gauthier1, and Rachid Deriche1

1Athena Project-Team, Inria Sophia Antipolis Méditerranée, Université Côte d'Azur, Sophia Antipolis, France

Three-dimensional Polarized Light Imaging (3D-PLI) is an optical approach presented as a good candidate for validation of diffusion Magnetic Resonance Imaging (dMRI) results such as orientation estimates (fiber Orientation Distribution Functions) and tractography. We developed an anlytical approach to reconstruct fiber ODFs from 3D-PLI datasets. From these fODFs, here we compute brain fiber tracts via dMRI-based probabilistic tractography algorithm. Reconstructed fODFs at different scales proves the ability to bridge the resolution gap between 3D-PLI and dMRI, demonstrating, therefore, a great promise to validate diffusion MRI tractography thanks to multi-scale fiber tracking based on 3D-PLI.

166
14:33
On the intrahemispheric connectivity of the monkey: a diffusion tractography and tract tracing analysis
Gabriel Girard1,2, Roberto Caminiti3,4, Alexandra Battaglia-Mayer3, Etienne St-Onge5, Karen S. Ambrosen6,7, Simon F. Eskildsen8, Kristine Krug9, Tim B. Dyrby7,10, Maxime Descoteaux5, Giorgio Innocenti11,12, and Jean-Philippe Thiran1,2

1Radiology Department, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland, 2Signal Processing Lab (LTS5), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 3Department of Physiology and Pharmacology, University of Rome SAPIENZA, Rome, Italy, 4Department of Anatomy, Histology, Forensic Medicine, and Orthopedics, University of Rome SAPIENZA, Rome, Italy, 5Sherbrooke Connectivity Imaging Lab, Computer Science Department, Université de Sherbrooke, Sherbrooke, QC, Canada, 6Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark, 7Danish Research Centre for Magnetic Resonance, Center for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark, 8Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark, 9Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom, 10Department of Applied Mathematics an Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark, 11Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden, 12Brain and Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland

In this work, we compare diffusion tractography with neuronal retrograde tract tracing of the frontal, cingulate and parietal areas of the monkey. We analyze the agreements between the tractography and the tracing for connected and not connected regions. We report an accuracy of 0.71 across all pairs of regions, with twice the number of true positive than false positive connections. Some regions show accuracy higher than 0.80, while other regions show accuracy lower than 0.6. A further analysis of the location of false positive and false negative connections will help understand the limitations and improve diffusion tractography algorithms.

167
14:45
SUper-REsolution TRACTography (SURE-TRACT) pipeline using self-similarity between diffusional and anatomical images
Hong Hsi Lee1,2, Ying Chia Lin1,2, Gregory Lemberskiy1,2, Benjamin Ades-aron1,2, Steven Baete1,2, Fernando E Boada1,2, Els Fieremans1,2, and Dmitry S Novikov1,2

1Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States, 2Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, United States

Here, we propose a model-free, self-similarity based SUper-REsolution TRACTography (SURE-TRACT) pipeline to increase the resolution of diffusion weighted images (DWIs) by translating the high spatial frequency details from the co-registered high-resolution anatomical image of the same subject. The generated high-resolution DWIs enable to identify fiber tracks and estimate biophysical parameters with greater anatomical detail. Validating our pipeline using Human Connectome Project data, we showed that the SURE-TRACT pipeline resolves partial volume effects, and is more flexible to different acquisition protocols than other recent machine-learning based algorithms.

168
14:57
A novel fiber-tracking algorithm using parallel transport frames
Dogu Baran Aydogan1 and Yonggang Shi2

1Department Neuroscience and Biomedical Engineering, Aalto University, Helsinki, Finland, 2Laboratory of NeuroImaging (LONI), Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, CA, United States

White matter fiber-tracking algorithms have remarkably improved during the last two decades. However, multiple validation studies warn about the reliability and reproducibility of results, and point out to the need for better algorithms. In propagation based tracking, connections are typically modeled as piece-wise linear segments. In this work, we propose a novel propagation based probabilistic tracker using parallel transport frames which is capable of generating geometrically smooth curves. Moreover, our tracker has a mechanism to reduce noise related propagation errors. Our experiments on FiberCup and Human Connectome Project data show visually and quantitatively superior results compared to three algorithms in MRtrix3.

169
15:09
Mapping short association fibres in the human visual system with ultra high resolution and high sensitivity diffusion MRI
Fakhereh Movahedian Attar1,2, Evgeniya Kirilina1,3, Daniel Hänelt1,2, Luke J Edwards1, Kerrin J Pine1, and Nikolaus Weiskopf1,4

1Neurophysics, Max Planck Institute for Human cognitive and Brain Sciences, Leipzig, Germany, 2International Max Planck Research School on Neuroscience of Communication: Function, Structure, and Plasticity, Leipzig, Germany, 3Neurocomputation and Neuroimaging Unit, Department of Education and Psychology, Free University Berlin, Berlin, Germany, 4Felix Bloch Institute for Solid State Physics, Faculty of Physics and Earth Sciences, Leipzig University, Leipzig, Germany

Short association fibres connect proximal cortical areas over short distances. These fibres are highly underrepresented in the current MRI-derived human brain connectome. We combined sub-millimetre resolution diffusion MRI, acquired with a 300 mT/m gradient system and high sensitivity coil for imaging the occipital cortex, with fMRI-driven retinotopic maps of V1/V2. These maps were used to identify the short V1-V2 connections in the human visual processing stream. V1-V2 connectivity was in agreement with previously reported anatomical and functional connectivities. Our results provide an important step towards the construction of a more complete MRI-derived human brain connectome via robust short fibre mapping.

170
15:21
Metrics that Matter: Improved statistical power to detect differences in tissue microstructure through dimensionality reduction
Maxime Chamberland1, Erika Raven1, Sila Genc1,2,3, Kate Duffy1, Greg Parker1, Chantal M.W. Tax1, Maxime Descoteaux4, and Derek K. Jones1,5

1School of Psychology, Cardiff University Brain Research Imaging Centre, Cardiff, United Kingdom, 2Department of Paediatrics, The University of Melbourne, Parkville, Australia, 3Developmental Imaging, Murdoch Childrens Research Institute, Parkville, Australia, 4Computer Science, University of Sherbrooke, Sherbrooke, QC, Canada, 5School of Psychology, Australian Catholic University, Victoria, Australia

Various diffusion metrics have been proposed for characterising tissue microstructure. However, it is unclear which metric best captures individual microstructural differences. One possible approach is to explore all available metrics. However, this increases the chance of Type I error and makes interpretation difficult. Using data-reduction approaches, we identified two principal components that capture 85% of the variance in diffusion measurements. The first captures properties related to hindrance, while the second reflects tissue complexity. We demonstrate the utility of this approach by showing significant correlations with age of these new metrics, whereas little to no effects were observed with any individual metric.

171
15:33
Improving the inter-subject reproducibility of diffusion MRI connectivity analysis by controlling the bundle reliability of individual streamlines at the group-level connectome.
Brian H. Silverstein1, Eishi Asano2,3, Yasuo Nakai4, Ayaka Sugiura2, Min-Hee Lee2, and Jeong-Won Jeong2,3

1Translational Neuroscience Program, Wayne State University, Detroit, MI, United States, 2Department of Pediatrics, Wayne State University, Detroit, MI, United States, 3Department of Neurology, Wayne State University, Detroit, MI, United States, 4Department of Neurological Surgery, Wakayama Medical University, Wakayama, Japan

Identifying true positives from diffusion weighted imaging (DWI)-based tractography is not trivial, and no universal gold standard has yet been developed. In this study, we introduce a method which utilizes the group-level streamline pathway distribution to determine inter-subject reproducibility of streamline bundles. At the participant level, streamlines that do not correspond to reproducible bundles are removed, resulting in improved reproducibility and increased fidelity when identifying differences between pathways. Additionally, we utilized electrical stimulation-based cortico-cortical evoked potentials to assess how well reliable bundles reflect underlying connectivity. Cleaned structural connectivity data was found to better correlate with electrophysiological connectivity.


Oral

MRS/MRSI: Application

Room 513D-F
Monday 13:45 - 15:45
Moderators: Andrea Gropman & Martin Krssák
172
13:45
Antibiotic rifaximin for treatment of chronic liver disease-induced HE: a longitudinal in vivo 1H-MRS study of brain metabolism
Emmanuelle Flatt1, Cristina Cudalbu2, Olivier Braissant3, Stefanita Mitrea2, Dario Sessa4, Valérie A. McLin4, and Rolf Grütter1

1LIFMET, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 2CIBM, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 3Service of Biomedecine, University Hospital of Lausanne, Lausanne, Switzerland, 4Swiss Center for Liver Disease in Children, Department of Pediatrics, University Hospitals Geneva, Geneva, Switzerland

Rifaximin is a commonly-used antibiotic to treat hepatic encephalopathy(HE), a complex neuropsychiatric syndrome caused by hepatic dysfunction. Rifaximin reduces the production of gut ammonia, the main toxin in HE pathogenesis.  We hypothesized that the effect of rifaximin on neurometabolic profile is dose-related. Therefore, in this study, the effects of rifaximin administered at 6x human-dose were assessed, in vivo and longitudinally on brain metabolites in bile-duct ligated(BDL) rats using 1H-MRS at 9.4T, biochemical and behavioral tests. They were compared with non-treated and human-dose treated rats. We showed that higher-dose rifaximin treatment was associated with positive effects on brain Gln,Glu and osmoregulation.

173
13:57
The neurometabolic correlates of motor performance across the adult lifespan: a study on the effects of age
Akila Weerasekera1, Oron Levin1, Brad King1, Kirstin Heise1, Diana Sima2, Sima Chalavi3, Celine Maes3, Lize Hermans3, Ronald Peeters4, Koen Cuypers3, Sabine Van Huffel3, Dante Mantini3, Uwe Himmelreich3, and Stephan Swinnen3

1University of Leuven, Leuven, Belgium, 2icometrix, Leuven, Belgium, 3University of Leuven, leuven, Belgium, 4University Hospital Leuven, Leuven, Belgium

Aging is associated with alterations in neurochemistry of the brain, which can be assessed by MR spectroscopy. However, it’s unclear which metabolites are critical for function of the motor network. We explored whether changes in the neurometabolites of the aging brain account for motor-declines in bimanual coordination. We focused on neurochemistry of motor-occipital cortices as both regions are nodes of sensorimotor network underlying bimanual control. Myo-inositol was relevant for predicting Perdue test, which examine manual dexterity and general bimanual skills whereas N-acetylaspartate was associated with bimanual coordination task. Findings indicate NAA and mI could serve as biomarkers for integrity of motor network.

174
14:09
An MRS investigation of superior visual search abilities in children with autism spectrum disorder: Evidence for enhanced top-down attentional filtering
David A Edmondson1,2, Pingyu Xia1, Brandon Keehn3, and Ulrike Dydak1,2

1School of Health Sciences, Purdue University, West Lafayette, IN, United States, 2Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States, 3Department of Speech, Language, & Hearing Sciences, Purdue University, West Lafayette, IN, United States

Processing strengths or “islets of ability” associated with autism spectrum disorder (ASD), especially in visual search, have been of continued interest as they provide insight into how those with ASD perceive the world around them. In typically-developing (TD) individuals, region-specific concentrations of GABA are associated with differences in attention and perception. ASD may be associated with an excitatory-inhibitory imbalance, however, it remains unclear how this may contribute to superior search abilities. To test this, 37 ASD and TD children participated in a magnetic resonance spectroscopy study using MEGA-semi-LASER to detect GABA concentrations in cortical regions associated with attention and perception.

175
14:21
Glial and axonal changes in mouse models of disease investigated with diffusion-weighted magnetic resonance spectroscopy at 11.7 T
Guglielmo Genovese1,2, Mathieu Santin1,2, Marco Palombo3, Julien Valette4, Clemence Ligneul5, Marie-Stéphane Aigrot2,6, Mehdi Felfli1, Nasteho Abdoulkader1, Dominique Langui2,6, Aymeric Millecamps2,6, Anne Baron-Van Evercooren2, Bruno Stankoff2, Stéphane Lehericy1,2, Alexandra Petiet1,2, and Francesca Branzoli1,2

1Centre de NeuroImagerie de Recherche (CENIR), Institut du Cerveau et de la Moelle épinère (ICM), Paris, France, 2Sorbonne Université, UMR S 1127, Inserm U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinère (ICM), Paris, France, 3Department of Computer Science and Centre for Medical Image Computing, University College of London (UCL), London, United Kingdom, 4Institute of biomedical imaging, Atomic Energy and Alternative Energies Commission (CEA), Fontenay-aux-Roses, France, 5Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Lisbon, Portugal, 6Core Facility ICM.Quant, Institut du Cerveau et de la Moelle épinère (ICM), Paris, France

The goal of this study was to evaluate the alterations of white matter microstructure in two different mouse models of white matter disease: the cuprizone (CPZ) model of multiple sclerosis and the Plp1 overexpressing (PLP-tg66) model of Pelizeaus-Merzbacher disease. To this end, we employed diffusion-weighted MR spectroscopy (DW-MRS) to measure concentrations and apparent diffusion coefficients of several metabolites in the corpus callosum of wild-type, CPZ and PLP-tg66 mice at 11.7 T. DW-MRS markers of axonal and glial degeneration were compared with histological measures.

176
14:33
Elevated brain glutamate levels in type 1 diabetes
Evita Wiegers1, Hanne Rooijackers2, Jack van Asten1, Cees Tack2, Arend Heerschap1, Bastiaan de Galan2, and Marinette van der Graaf1,3

1Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, Netherlands, 2Internal Medicine, Radboud university medical center, Nijmegen, Netherlands, 3Pediatrics, Radboud university medical center, Nijmegen, Netherlands

Type 1 diabetes affects the structure and functioning of the brain, but the neurochemical mediators that may accompany these negative effects are largely unknown. We investigated brain metabolite levels with 1H MRS in patients with type 1 diabetes and normal awareness of hypoglycemia, patients with impaired awareness of hypoglycemia (IAH) and non-diabetic controls. Brain glutamate levels were elevated in type 1 diabetes and correlated with glycemic control and age of disease onset, but not with burden of hypoglycemia as reflected by IAH. This suggests a potential role for glutamate as early marker of hyperglycemia-induced cerebral decline in type 1 diabetes.

177
14:45
Remote metabolic profile changes in subacute spinal cord injury
Patrik O Wyss1,2,3, Markus F Berger1, and Anke Henning2,3

1Department of Radiology, Swiss Paraplegic Centre, Nottwil, Switzerland, 2Institute for Biomedical Engineering, ETH and University of Zurich, Zurich, Switzerland, 3Max-Planck Institute for Biological Cybernetics, Tuebingen, Germany

Not a single MR marker has been identified to predict patient outcome in spinal cord injury (SCI) rehabilitation. Therefore, we applied magnetic resonance spectroscopy (MRS) to examine metabolite concentration in the pons around 10 weeks after injury and identify group differences in complete and incomplete SCI at the time of the MRS acquisition.

178
14:57
In vivo cystathionine detection in gliomas by edited 1H magnetic resonance spectroscopy
Francesca Branzoli1,2, Dinesh K Deelchand3, Anna Luisa Di Stefano4,5, Marc Sanson2,4,6, Stéphane Lehéricy1,2, and Małgorzata Marjańska3

1Centre de NeuroImagerie de Recherche (CENIR), Institut du Cerveau et de la Moelle épinère (ICM), Paris, France, 2Sorbonne Université, UMR S 1127, Inserm U 1127, CNRS UMR 7225, Paris, France, 3Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, United States, 4AP-HP, Hôpital de la Pitié-Salpêtrière, Service de Neurologie 2, Paris, France, 5Department of Neurology, Foch Hospital, Suresnes, Paris, France, 6Onconeurotek tumor bank, Institut du Cerveau et de la Moelle épinère (ICM), Paris, France

This study reports the first measurement of cystathionine in vivo. Cystathionine was measured using the edited magnetic resonance spectroscopy (MRS). The identification of cystathionine was confirmed by comparing in vivo spectra acquired in gliomas with the cystathionine spectrum measured in a phantom at physiological pH and temperature and with a simulated spectrum generated using accurate chemical shifts and J-coupling constants. The noninvasive detection of cystathionine by MRS may represent a new in vivo marker of glioma subtypes which will benefit diagnosis and treatment of patients with gliomas.

179
15:09
Importance of early spectral variations during 48 months of longitudinal follow-up MRI and MRS in 100 patients treated glioblastoma
Jean-Marc CONSTANS1, A. Heintz2, J.P. Chombar2, F. Dallery2, S. Metambou2, O. Seloi 2, N. Deleval 2, D. Michel2, S. Boussida2, R. Hanafi2, C. Corcy2, W. Dou 3, S. Ruan4, D. Le Gars 2, H. Deramond2, A. Houessinon2, A. Fichten 2, M. Lefranc2, A. Coutte2, P. Toussaint 2, C. Desenclos 2, B. Chauffert 2, and M. Boone 2

1Radiology, CHU et Université Picardie Jules Vernes, Amiens, France, Amiens, France, Metropolitan, 2CHU et Université Picardie Jules Vernes, Amiens, France, Amiens, France, Metropolitan, 3Tsinghua University, Beijing, China, Beijing, China, 4Université de Rouen, France, Rouen, France

MRS with Cho/Cr, Lac/Cr, CH2/Cr and NAA/Cr ratios, could be more sensitive than MRI and could, in some cases, be predictive of worsening in glioblastomas follow-up. These spectroscopic changes occurred well before clinical deterioration. There is a large variability, but repetition and modelisation of spectroscopic measurements during longitudinal follow-up could allow us to diminish it and to improve glioblastomas prognostic evaluation especially at and after relapses. Studying the relationship between MRS measures, segmentation and perfusion parameters could lead to better understanding of therapeutic response and patients selection, especially with regard to chemotherapy and antiangiogenic molecules and  in future stress modulators.

180
15:21
Metabolite relaxation and diffusion abnormalities in the white matter of first-episode schizophrenia: a longitudinal study
Xi Chen1,2, Xiaoying Fan1, Talia Cohen1, Margaret Gardner1, Fei Du1,2, and Dost Ongur1,2

1McLean Hospital, Belmont, MA, United States, 2Harvard Medical School, Boston, MA, United States

Microstructural abnormalities in the white matter are important in the pathophysiology of schizophrenia. Unlike to unspecific nature of water, MRS can probe the brain's intracellular microenvironment through the measurement of transverse relaxation and diffusion of neurometabolites and even providecell-specific information. In this study, we worked with first episode schizophreniapatients so as to obviate the effects of medications and toxic effects of chronic psychosis. A combination of the T2-MRS and DTS techniques were applied in a longitudinal study. NAA T2 and ADC showed more sensitive changes compared to water at the early stage of disease.

181
15:33
Spiral-MRSI and tissue segmentation of normal-appearing white matter and white matter lesion load in relapsing remitting Multiple Sclerosis.
Oun Al-iedani1,2, Karen Ribbons 2,3, Jeannette Lechner-Scott2,3,4, Scott Quadrelli5, Rodney Lea2, Ovidiu Andronesi6, and Saadallah Ramadan1,2

1School of Health Sciences, University of Newcastle, Newcastle, Australia, 2Hunter Medical Research Institute, Newcastle, Australia, 3Department of Neurology, John Hunter Hospital, Newcastle, Australia, 4School of Medicine and Public Health, University of Newcastle, Newcastle, Australia, 5Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia, 6Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States

The study evaluated a novel Fast-MRSI technique with tissue segmentation in determining metabolic alterations in NAWM and WM-lesions in MS compared to healthy controls. 3D-MPRAGE and 3D-Spiral-MRSI covering 70% of total brain on 16 RRMS and 9 HCs (aged 22-55yrs) were used. MRSI was processed using MATLAB and LCModel. Findings  revealed that (NAA/tCr) in WM-lesions was significantly lower than NAWM-MS and HCs. Volumetric segmentation using SIENAX, revealed a significant WBV reduction and CSF increase in RRMS compared to HCs. Fast-MRSI may enhance diagnosis and clinical monitoring of MS patients, and is sensitive in diagnosing MS even in NAWM.


Oral

Neuropsychiatry & Psychoradiology

Room 518A-C
Monday 13:45 - 15:45
Moderators: Meiyun Wang & Steven Williams
182
13:45
Anatomic alterations in amygdala subregions in medication-free patients with obsessive-compulsive disorder
Lianqing Zhang1, Xinyu Hu1, Hailong Li1, Shi Tang1, Lu Lu1, Xuan Bu1, Xiaoxiao Hu1, Yingxue Gao1, Yanlin Wang1, yanchun Yang2, John A. Sweeney1,3, Qiyong Gong1, and Xiaoqi Huang1

1Department of Radiology, Huaxi MR Research Center (HMRRC), Sichuan University, Chengdu, China, 2Department of Psychiatry, Sichuan University, Chengdu, China, 3Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, United States

Most previous human neuroimaging studies measured the volume of amygdala as a whole, however, the amygdala consists of several functionally distinct subnuclei. Recent advances in structural MR image segmentation technique have made it possible to study amygdala subnuclei volumes with a robust, automatic approach using a Bayesian inference-based atlas building algorithm. Using this algorithm, we for the first time provide a distinctive profile of amygdala subnuclei volume abnormality in a relatively large sample of drug-free obsessive-compulsive disorder patients, and provide an insight that these subnuclei contribute to different aspect of neuropathology in the disorder.

183
13:57
Mediators of the real-time fMRI amygdala neurofeedback training effect on PTSD symptom reduction: a whole brain structural equation model mapping analysis
Masaya Misaki1, Raquel Phillips1, Vadim Zotev1, Frank Krueger2, Matthew Feldner3, and Jerzy Bodurka1,4

1Laureate Institute for Brain Research, Tulsa, OK, United States, 2Neuroscience Department, George Mason University, Fairfax, VA, United States, 3Department of Psychological Science, University of Arkansas, Fayetteville, AR, United States, 4Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK, United States

We determined mediators of the real-time fMRI neurofeedback (rtfMRI-nf) amygdala training inducing PTSD symptom reduction in combat veterans. Thirty-six veterans with PTSD (25 experimental group and 11 control group receiving a feedback from a control region) completed three rtfMRI-nf training sessions in separate days. We employed a novel whole brain structural equation model mapping (SEMM) analysis to identify brain regions that mediated the effects of the rtfMRI-nf procedure on PTSD symptoms. Results revealed that PTSD symptom reduction in the experimental group was mediated by lower activation than the control group in default mode network regions during the neurofeedback training.

184
14:09
Imaging hippocampal glutamate alterations in a 22q11.2 deletion syndrome mouse model of schizophrenia
Puneet Bagga1, David Roalf2, Hari Hariharan1, Anderson Stewart2, Douglas Coulter3, Raquel Gur2, and Ravinder Reddy1

1Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States, 3Department of Pediatrics, University of Pennsylvania, Philadelphia, PA, United States

Schizophrenia (SZ) is a common, severe mental illness caused by neurobiological disturbances in glutamate and dopamine. Glutamate is the major excitatory neurotransmitter in the brain and can be detected using MR spectroscopy and glutamate-weighted chemical exchange saturation transfer (GluCEST) MRI. In this study, we performed high-resolution GluCEST MRI in the 22q11.2 deletion syndrome (22q11.2DS) mouse model of SZ to evaluate glutamatergic alterations in the dorsal and ventral hippocampus. The GluCEST contrast was found to be lower in the hippocampus of 22q11.2DS mice compared to that in the age-matched control mice indicating the lower hippocampal glutamate level in the preclinical model of SZ.

185
14:21
Emotion Self-Regulation Training with Simultaneous Real-Time fMRI and EEG Neurofeedback in Major Depression
Vadim Zotev1, Ahmad Mayeli1,2, Masaya Misaki1, and Jerzy Bodurka1,3

1Laureate Institute for Brain Research, Tulsa, OK, United States, 2Electrical and Computer Engineering, University of Oklahoma, Tulsa, OK, United States, 3Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK, United States

We report a study of emotion self-regulation training in patients with major depressive disorder (MDD) using simultaneous real-time fMRI and EEG neurofeedback (rtfMRI-EEG-nf). Emotion-relevant target nf measures included fMRI activities of the left amygdala and left rACC, and frontal EEG asymmetries in the alpha and high-beta bands. MDD patients successfully learned to upregulate all four measures simultaneously using rtfMRI-EEG-nf during a happy emotion induction task. EEG-fMRI data analyses provided new insights into mechanisms of rtfMRI-EEG-nf. These findings may lead to development of more efficient neurotherapies for MDD.

186
14:33
Discrete Regions of Gray Matter Loss Underlie Major Depressive Disorder: A Replication and Expanded Investigation
Sarah C Hellewell1, Thomas Welton1, Jerome J Maller1,2, Matthew Lyon1, Mayuresh S Korgaonkar3, Stephen H Koslow4, Leanne M Williams5, Evian Gordon1,6, A John Rush7,8, and Stuart M Grieve1,9

1Sydney Translational Imaging Laboratory, Heart Research Institute, Charles Perkins Centre, University of Sydney, Sydney, Australia, 2General Electric Healthcare, Melbourne, Australia, 3The Brain Dynamics Centre, Westmead Millennium Institute and Sydney Medical School, Sydney, Australia, 4Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, United States, 5Sierra-Pacific Mental Illness Research, Education, and Clinical Center (MIRECC), Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, United States, 6Brain Resource Ltd, Sydney, Australia, 7Duke-National University of Singapore, Singapore, Singapore, 8Department of Psychiatry, Duke Medical School, Durham, NC, United States, 9Department of Radiology, Royal Prince Alfred Hospital, Sydney, Australia

The aims of this study were to construct a biomarker based on anatomical regions of profoundly reduced gray matter volume in subjects with major depressive disorder. Our biomarker successfully discriminated MDD subjects from controls at an accuracy of 73%, suggesting a possible role for network measurements of GM susceptibility in MDD.

187
14:45
Neural Correlates of Rumination in Normal and Major Depressive Disorder: A Brain Network Analysis
Yael Jacob1, Laurel Morris1, Kuang-Han Huang1, Molly Schneider1, Gaurav Verma1, James Murrough1, and Priti Balchandani1

1Icahn School of Medicine at Mount Sinai, New York, NY, United States

Major depressive disorder (MDD) patients exhibit higher rumination levels; repetitive thinking and focus on negative states. Rumination is known to be associated with brain cortical midline and limbic structures, yet, the underlying brain network topological organization remains unclear. Implementing a graph-theory analysis we tested whether whole brain network connectivity hierarchies during fMRI resting state are associated with rumination. We found a significant correlation between right caudal anterior cingulate (cACC) connectivity strength and subjective rumination tendency. This result emphasize the cACC impact during self-reflective processing, which might serve as biomarker for clinical diagnosis.

188
14:57
PET derived Raphe Nuclei [11C]-CUMI binding potential is associated with MR derived diffusion entropy in the frontal and temporal lobes
Mario Serrano-Sosa1, Karl Spuhler1, Christine DeLorenzo2, Ramin Parsey2, and Chuan Huang2,3

1Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States, 2Psychiatry, Stony Brook Medicine, Stony Brook, NY, United States, 3Radiology, Stony Brook Radiology, Stony Brook, NY, United States

Using a new DTI processing technique, named diffusion entropy, and dynamic PET data we observed a statistically significant inverse correlation between diffusion entropy and [11C]-CUMI binding potential (BPF) in a dataset with bipolar, major depressive disorder patients and controls. This newfound analysis can give rise to further understanding the pathophysiology that undermines psychiatric diseases and, also, a non-invasive, non-ionizing radiation procedure to estimate [11C]-CUMI BPF.

189
15:09
Thalamic Substructures in Alcoholism: Volume Deficits and Functional Correlates
Natalie Zahr1,2, Kilian Marie Pohl1, and Manoj Saranathan3

1Neuroscience, SRI International, Menlo Park, CA, United States, 2Stanford University, Stanford, CA, United States, 3Department of Medical Imaging, The University of Arizona Health Sciences, Tucson, AZ, United States

Volumes of 5 thalamic substructures—mediodorsal (MD), anterior (AV), ventral lateral posterior (VLp), ventral posterior lateral (VPl), pulvinar (Pul))—were quantified using a novel automated segmentation algorithm in 40 individuals with Alcohol Use Disorder (AUD) and 60 controls (Con). Multiple regressions on supratentorial-volume-corrected measures revealed that volumes of AV, VLp, VPl, and Pul were smaller with older age, and volumes of AV, VLp, Pul, and MD were smaller in the AUD than Con group. Functional ramifications of thalamic substructures indicated relations between back pain and smaller Pul and VLp volumes, and poor ataxia scores with smaller VPI volumes.

190
15:21
Mapping atypical functional connectome organization and hierarchy in autism spectrum disorders
Seok-Jun Hong1,2, Reinder Vos De Wael1, Richard A.I. Bethlehem3, Sara Lariviere1, Casey Paquola1, Sofie L. Valk4, Adriana Di Martino5, Daniel S. Margulies6, Michael P. Milham2,7, Jonathan Smallwood8, and Boris C. Bernhardt1

1Multimodal Imaging and Connectome Analysis Lab, Montreal Neurological Institute, Montreal, Quebec, QC, Canada, 2Center for the Developing Brain, Child Mind Institute, New York, NY, United States, 3Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom, 4Institute of Systems Neuroscience, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany, 5Autism Center, Child Mind Institute, New York, NY, United States, 6Institut de Cerveau et de la Moelle épinière, Hôpital Pitié Salpêtrière, Paris, France, 7Center for Biomedical Imaging and Neuromodulation, Nathan S. Kline Institute for Psychiatric Research, New York, NY, United States, 8Department of Psychology, University of York, York, United Kingdom

One paradox of autism is the co-occurrence of deficits in sensory and higher-order socio-cognitive processing. The current work examined whether these phenotypical patterns may relate to abnormal macroscale hierarchy affecting both unimodal and transmodal networks. Combining connectome gradient and stepwise connectivity analysis based on task-free fMRI, we demonstrated atypical connectivity transitions between sensory and higher-order default mode regions in a large cohort of autism individuals. Supervised pattern learning revealed that hierarchical features predicted deficits in social cognition and low-level behavioral symptoms. Our findings provide new evidence for network imbalances in autism, offering a parsimonious reference to consolidate its diverse features. 

191
15:33
Modulation of dorsolateral prefrontal cortex GABA and Glx (glutamate + glutamine) levels following repetitive magnetic stimulation therapy of major depressive disorder
Pallab K Bhattacharyya1,2, Murat Altinay 3, Jian Lin1, and Amit Anand3

1Imaging Institute, Cleveland Clinic, Cleveland, OH, United States, 2Radiology, Cleveland Clinic Lerner College of Medicine, Cleveland, OH, United States, 3Neurological Institute, Cleveland Clinic, Cleveland, OH, United States

Abnormalities of Gamma Amino Butyric Acid (GABA), the major inhibitory neurotransmitter, and Glx (glutamate, major excitatory neurotransmitter + glutamine) have been implicated in the pathology of depression. Modulation of GABA and Glx at left dorsolateral prefrontal cortex, the site of application of repetitive transcranial magnetic stimulation (rTMS) to treat major depressive disorder for patients not adequately responsive to medication treatment, was investigated using MEGA-PRESS spectroscopy. No change in GABA level was observed, while Glx/creatine level increased with rTMS therapy. Patients with higher Glx/Creatine level tended to respond better to rTMS, and the response was inversely correlated with increase in Glx/Creatine.


Oral

Cutting-Edge Advances in Cancer Imaging

Room 520A-F
Monday 13:45 - 15:45
Moderators: Mukund Seshadri
192
13:45
Model-free denoising of multi b-value diffusion-weighted MR images using principal component analysis: simulations and in vivo results
Oliver Jacob Gurney-Champion1, David J Collins2, Andreas Wetscherek1, Mihaela Rata2, Remy Klaassen3, Hanneke W M van Laarhoven3, Kevin J Harrington1, Uwe Oelfke1, and Matthew R Orton2

1The Institute of Cancer Research and the Royal Marsden NHS Foundation Trust, London, United Kingdom, 2Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research and the Royal Marsden NHS Foundation Trust, London, United Kingdom, 3Cancer Center Amsterdam, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands

We present a principal component analysis (PCA) toolkit for mode-free denoising of multi b-value diffusion-weighted images for clinical use. In simulations, PCA-denoising suppressed the random noise equally well (up to 55%) as synthetic MRI. Contrary to synthetic MRI (systematic error up to 29% of total signal intensity), PCA-denoising did not introduce any systematic errors (<2%). In volunteer and patient image data, PCA-denoising resulted in sharper and less noisy images than synthetic MRI, which resulted in sharper and clearer tumour boundaries. In conclusion, our PCA-denoising toolkit is promising for denoising b-value images for clinical use.

193
13:57
DCE MRI-Based Computational Modeling of Interstitial Fluid Pressure and Velocity in Head and Neck Cancer: Initial Analysis
Eve LoCastro1, Yonggang Lu2, Ramesh Paudyal1, Yousef Mazaheri1,3, Vaios Hatzoglou3, Amaresha K. Shridhar1, Alan Ho4, Nancy Lee5, Joseph Deasy1, and Amita Shukla-Dave1,3

1Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Radiology, Medical College of Wisconsin, Milwaukee, WI, United States, 3Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, United States, 4Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, United States, 5Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, United States

We applied computational fluid modeling to head-and-neck cancer patients' DCE-MRI data using permeability maps from extended Tofts' model and tumor geometry from imaging. Interstitial fluid pressure (IFP) maps generated from computational fluid modeling depict heterogeneous distribution of elevated IFP and velocity in tumor tissue. We found  significant correlation between tumor volume and IFP.

194
14:09
Deep residual learning of radial under sampling artefacts for real-time MR image guidance during radiotherapy
Bjorn Stemkens1,2, Cheryl Sital1,2,3, Max Blokker1,2,4, Tom Bruijnen1, Jan JW Lagendijk1, Rob HN Tijssen1, and Cornelis AT van den Berg1

1Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands, 2MR Code B.V., Zaltbommel, Netherlands, 3Biomedical Engineering, University of Technology Eindhoven, Eindhoven, Netherlands, 4Medical Natural Sciences, VU Amsterdam, Amsterdam, Netherlands

MRI-guided radiotherapy using hybrid MR-Linac systems, requires high spatiotemporal resolution MR images to guide the radiation beam in real time. Here, we investigate the concept of deep residual learning of radial undersampling artifacts to decrease acquisition time and minimize extra reconstruction time by using the fast forward evaluation of the network. Within 8-10 milliseconds most streaking artifacts were removed for undersampling rates between R=4 and R=32 in the abdomen and brain, facilitating real-time tracking for MR-guided radiotherapy.

195
14:21
Amid Proton Transfer-Weighted Imaging vs. Diffusion-Weighted Imaging vs. FDG-PET/CT: Capability for Management of Solitary Pulmonary Nodules
Yoshiharu Ohno1,2, Masao Yui3, Takeshi Yoshikawa1,2, Shinichiro Seki1,2, Katsusuke Kyotani4, and Takamichi Murakami4,5

1Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan, 2Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Japan, 3Canon Medical Systems Corporation, Otawara, Japan, 4Center for Radiology and Radiation Oncology, Kobe University Hospital, Kobe, Japan, 5Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan

    We hypothesized that APTw imaging had equal or better potential for diagnosis of SPNs and prediction of postoperative recurrence prediction in postoperative lung cancer patients, when compared with DWI and FDG-PET/CT.  In addition, multiparametric approach among all three methods had better potential than single-parametric approach on each method in this setting.  The purpose of this study was to compare the diagnosis and prediction capabilities of pulmonary nodules among single- and multi-parametric approaches by APTw imaging, DWI, and FDG-PET/CT.  

196
14:33
A Noninvasive Comparison Study between Human Gliomas with IDH1 and IDH2 Mutations by MR Spectroscopy
Xin Shen1, Natalie Voets2, Sarah Larkin2, Nick de Pennington2, Puneet Plaha3, Richard Stacey3, James Mccullagh2, Christopher Schofield2, Stuart Clare2, Peter Jezzard2, Tom Cadoux-Hudson3, Olaf Ansorge2, and Uzay Emir1,2,4

1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States, 2University of Oxford, Oxford, United Kingdom, 3Oxford University Hospitals NHS Trust, Oxford, United Kingdom, 4School of Health Sciences, Purdue University, West Lafayette, IN, United States

The oncogenes that are expressed in gliomas reprogram particular pathways of glucose, amino acid, and fatty acid metabolism. Mutations in the isocitrate dehydrogenase genes (IDH1/2) in diffuse gliomas are associated with abnormally high 2-hydroxyglutarate (2-HG) levels. Non-invasive measurement of 2-HG via in vivo 1H magnetic resonance spectroscopy (MRS) can be used to differentiate mutant cytosolic IDH1 from mitochondrial IDH2 in gliomas. 

197
14:45
Cystathionine as a marker for 1p/19q codeleted gliomas by in vivo magnetic resonance spectroscopy
Francesca Branzoli1,2, Clément Pontoizeau3, Anna Luisa Di Stefano4,5, Dinesh K Deelchand6, Romain Valabregue1,2, Stéphane Lehéricy1,2, Marc Sanson2,4,7, Chris Ottolenghi3, and Małgorzata Marjańska6

1Centre de NeuroImagerie de Recherche (CENIR), Institut du Cerveau et de la Moelle épinère (ICM), Paris, France, 2Sorbonne Université, UMR S 1127, Inserm U 1127, CNRS UMR 7225, Paris, France, 3Centre de Référence des Maladies Métaboliques, Service de Biochimie Métabolique, Hôpital Necker and Université Paris Descartes, Paris, France, 4AP-HP, Hôpital de la Pitié-Salpêtrière, Service de Neurologie 2, Paris, France, 5Department of Neurology, Foch Hospital, Suresnes, Paris, France, 6Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN, United States, 7Onconeurotek tumor bank, Institut du Cerveau et de la Moelle épinère (ICM), Paris, France

Molecular markers such as mutation in isocitrate dehydrogenase (IDH) and codeletion of chromosome arms 1p and 19q (1p/19q codeletion) have highly benefited diagnosis and prognosis in brain gliomas. However, the biological effects of 1p/19q codeletion are still not clear. We report selective accumulation of cystathionine in IDH-mutated, 1p/19q codeleted gliomas observed by edited 1H magnetic resonance spectroscopy. Noninvasive detection of cystathione enables identification of glioma subtypes in vivo and opens up the possibility of investigating nonivasively cancer-specific metabolic pathways.

198
14:57
The effects of neoadjuvant chemotherapy on axillary lymph node volume and compacity in breast cancer patients: an MRI study
Renee Faith Cattell1, Krupal Patel1, Thomas Ren1, James Kang1, Pauline Huang1, Jason Ha1, Ashima Muttreja1, Jules Cohen1, Haifang Li1, Lea Baer1, Cliff Bernstein1, Sean Clouston1, Roxanne Palermo1, and Timothy Duong1

1Stony Brook University, Stony Brook, NY, United States

Axillary lymph node involvement in breast cancer is associated with higher risk of distant metastasis and recurrence. This study evaluated whether MRI can be used to longitudinally monitor effects of neoadjuvant chemotherapy on axillary lymph nodes in situ. Nodal volume and compacity were analyzed with respect to treatment responders and non-responders. Comparisons with unaffected nodes were made. Neoadjuvant chemotherapy significantly reduced nodal volume of the affected nodes in both responders and non-responders. Nodal volumes of the responders normalized whereas those of the partial-responders did not normalize completely. This approach may prove useful for monitoring cancer treatment effects on nodal morphology. 

199
15:09
Lymphovascular invasion correlates with elevated tumor pressure as quantified by MR Elastography: initial results from a breast cancer trial
Daniel Fovargue1, Sweta Sethi2,3, Jack Lee1, Marco Fiorito1, Adela Capilnasiu1, Stefan Hoelzl1, Jurgen Henk Runge1,4, Jose de Arcos1, Keshthra Satchithananda5, Arnie Purushotham3, David Nordsletten1,6, and Ralph Sinkus1,7

1School of Biomedical Engineering & Imaging Sciences, King's College London, London, United Kingdom, 2Guy's and St.Thomas' NHS Foundation Trust, London, United Kingdom, 3Division of Cancer Studies, King's College London, London, United Kingdom, 4Department of Radiology and Nuclear Medicine, Amsterdam UMC, Amsterdam, Netherlands, 5King's College Hospital, London, United Kingdom, 6Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States, 7U1148, INSERM, Paris, France

Gauging metastatic propensity is crucial as it impacts decision making in oncology (e.g. whether a patient should receive surgery immediately or neoadjuvant chemotherapy). Interstitial fluid pressure (IFP) is known to correlate with microvascular invasion, a proxy for metastatic potential. However, no current imaging biomarkers correlate with this. We present a method to noninvasively calculate a total tumor pressure (which IFP contributes to). The method reconstructs pressure via nonlinear biomechanics and MR Elastography and is validated in simulations and phantoms. Elevated pressure values from a cohort of 16 breast cancer patients correlate with lymphovascular invasion possibly providing a much sought-after biomarker.

200
15:21
Noninvasive MRI mapping of malignant infiltration into lymph nodes
Inês Santiago1, João Santinha1, Andrada Ianus1,2, Antonio Galzerano1, Maria Barata1, Nickolas Papanikolaou1, Antonio Beltran1, Celso Matos1, and Noam Shemesh1

1Champalimaud Foundation, Lisbon, Portugal, 2Centre for Medical Image Computing, UCL, London, United Kingdom

Mapping malignant infiltration into lymph nodes can have a critical impact on patient decision making. We predicted that multigradient echo (MGE) experiments could reflect cellularity and cell-size changes due to underlying susceptibility distributions. Lymph nodes extracted from rectal cancer patients exhibited the predicted non-monotonic and non-mono-exponential MGE signal decay, which provided insights into the underlying microstructure. A simple model distinguished benign from malignant nodal tissue and the differences were at least partially explained by differences in cellularity and cell size. These results can impact lymph node staging accuracy, as already corroborated by our pilot results in-vivo, upon rectal cancer staging, at 1.5T.

201
15:33
Androgen Independence Leads to Altered Metabolism in Prostate Cancer Cell and Murine Models
Jinny Sun1, Justin Delos Santos1, Robert Bok1, Romelyn Delos Santos1, Mark Van Criekinge1, Daniel B Vigneron1, Renuka Sriram1, and John Kurhanewicz1

1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States

This study demonstrated significant increases in flux through glycolysis, oxidative metabolism, and glutaminolysis associated with androgen independence using patient-derived cell lines and a treatment-driven murine model. This data supports using a combination of hyperpolarized [1-13C]pyruvate, [2-13C]pyruvate and  [5-13C]glutamine to noninvasively discriminate between androgen-dependent and androgen-independent prostate cancer in future patient studies using hyperpolarized 13C MRI.


Oral

fMRI: Multimodal

Room 710A
Monday 13:45 - 15:45
Moderators: Shella Keilholz & Jeroen Siero
202
13:45
Neural activity temporal pattern dictates the long-range brain-wide propagation pathways: An optogenetic fMRI study
Alex T. L. Leong1,2, Xunda Wang1,2, Celia M. Dong1,2, Russell W. Chan1,2, and Ed X. Wu1,2

1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China, 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China

The current overarching challenge in neuroscience is to establish an integrated understanding of the brain networks, particularly the spatiotemporal patterns of neural activities that give rise to functions and behavior. fMRI provides the most versatile neuroimaging platform for mapping large-scale activities in vivo. However, on its own, many important details of the underlying network activities remain unresolved. Here, we employed fMRI in combination with pulsed optogenetic stimulation paradigms to probe the spatiotemporal dynamics and functions of the well-defined topographically-organized somatosensory thalamo-cortical network. We reveal unique long-range propagation pathways that are dictated by distinct neural activity temporal patterns initiated from the thalamus.

203
13:57
Spanning spatiotemporal scales with simultaneous mesoscopic calcium imaging and functional MRI
Evelyn MR Lake1, Xinxin Ge2, Xilin Shen1, Peter Herman1, Fahmeed Hyder1,3, Jessica A Cardin4,5, Michael J Higley4,5,6,7, Dustin Scheinost1,8,9, Xenophon Papademetris1,3, Michael C Crair2,5,10, and R Todd Constable1,11,12

1Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, United States, 2Department of Neurobiology, Yale University, New Haven, CT, United States, 3Department of Biomedical Engineering, Yale University, New Haven, CT, United States, 4Department of Neuroscience, Yale University, New Haven, CT, United States, 5Kavli Institute for Neuroscience, Yale University, New Haven, CT, United States, 6Program in Cellular Neuroscience, Yale University, New Haven, CT, United States, 7Neurodegeneration and Repair, Yale University, New Haven, CT, United States, 8Department of Statistics and Data Science, Yale University, New Haven, CT, United States, 9The Child Study Center, Yale University, New Haven, CT, United States, 10Department of Ophthalmology and Visual Science, Yale University, New Haven, CT, United States, 11Department of Neurosurgery, Yale University, New Haven, CT, United States, 12Interdepartmental Neuroscience Program, Yale University, New Haven, CT, United States

Neuroscience interrogates brain function across multiple spatiotemporal scales. Yet, most research is confined to one spatiotemporal milieu limiting translation of knowledge across scales. Here we span spatiotemporal scales having built a custom apparatus and analytical framework for simultaneous wide field mesoscopic Ca2+ imaging of the entire cortex and fMRI at 11.7T in mice. We describe the new hardware/software, and present three findings: there is correspondence between spontaneous fluctuations in the magnitude of Ca2+ and fMRI evoked responses, Ca2+ and fMRI connectivity metrics are stable throughout an imaging session, and there is correspondence between Ca2+ and fMRI spontaneous activity patterns.

204
14:09
Multimodal awake mouse imaging: from two-photon microscopy to BOLD-fMRI
Michèle Desjardins1,2, Kılıç Kıvılcım2,3, Martin Thunemann2, Céline Mateo2, Dominic Holland2, Christopher G. L. Ferri2, Jonathan Cremonesi2, Boaqiang Li4, Qun Cheng2, Kimberly L Weldy2, Payam A Saisan2, David Kleinfeld2, Takaki Komiyama2, Thomas T Liu2, Robert Bussell2, Eric C Wong2, Miriam Scadeng2, Andrew K Dunn5, David A Boas3, Sava Sakadžić4, Joseph B Mandeville4, Richard B Buxton2, Anders M Dale2, and Anna Devor2

1Physique, génie physique et optique, Université Laval, Québec, QC, Canada, 2University of California San Diego, La Jolla, CA, United States, 3Boston University, Boston, MA, United States, 4Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA, United States, 5University of Texas at Austin, Austin, TX, United States

Functional Magnetic Resonance Imaging (fMRI) in awake behaving mice is well positioned to bridge the detailed cellular-level view of brain activity, which has become available due to recent advances in microscopic optical imaging and genetics, to the macroscopic scale of human noninvasive observables. Here, we demonstrate Blood Oxygen Level Dependent (BOLD) fMRI in awake mice implanted with chronic transparent cranial ''windows'', compatible with two-photon microscopy, optical imaging, and optogenetic light stimulation. We thus provide a proof of feasibility for multimodal imaging approaches in awake mice, which in the future can be extended to behavioral studies and biomedical applications.

205
14:21
Ultra high field BOLD measurements combined with simultaneous determination of blood oxygenation and blood volume by optical imaging
Rebekka Bernard1, Klaus Scheffler1,2, and Rolf Pohmann1

1Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 2Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany

To disentangle the different parameters contributing to the BOLD effect, a combined setup for intrinsic optical imaging and ultra high field fMRI in rats was designed, using a magnetic field compatible, high sensitivity camera and professional optical components. By illumination of the brain surface with light in four different wavelengths, oxygenation and CBV was observed concurrently with fMRI during forepaw stimulation. Simultaneous measurement of those parameters can help to better understand the BOLD effect and to add additional value to both optical imaging and fMRI experiments.

206
14:33
Simultaneous fMRE and fMRI measures the viscoelastic and BOLD responses of the human brain to functional activation in the visual cortex
Patricia S. Lan1, Kevin J. Glaser2, Richard L. Ehman2, and Gary H. Glover3

1Bioengineering, Stanford University, Stanford, CA, United States, 2Radiology, Mayo Clinic, Rochester, MN, United States, 3Radiology, Stanford University, Stanford, CA, United States

Here, we demonstrate a novel multi-modal method to simultaneously acquire robust fMRE and fMRI activation maps. A block paradigm of 24s ON (flashing checkerboard at 10Hz) and 24s OFF (fixation cross) was used and images were acquired with a single-shot spin-echo EPI MRE sequence. Our results show that tissue stiffness within the visual cortex increases 6-12% with visual stimuli. Furthermore, the fMRE and fMRI activation maps agree and overlap spatially within the visual cortex, providing convincing evidence that fMRE is possible in the cortex.

207
14:45
Functional Magnetic Resonance Electrical Impedance Tomography of Aplysia abdominal ganglion
Fanrui Fu1, Munish Chauhan1, and Rosalind Sadleir1

1Arizona State University, Tempe, AZ, United States

Functional Magnetic resonance electrical impedance tomography (fMREIT) has the potential to directly image neural activity. In our tests, we used the Aplysia abdominal ganglion (AAG) as a neuronal activity source. Potassium chloride (KCl) was used to modulate neuronal activity. Analysis of magnitude images, subtracted MREIT phase images and Laplacian of MREIT Bz images was performed to evaluate the difference in MREIT images with and without neuronal activity. 

208
14:57
Baseline Striatal Dopamine Binding Potential Predicts Functional Connectivity to Ventral Tegmental Area in Control but not in MDD: A Simultaneous [11C] Raclopride PET-fMRI Study
Xue Zhang1,2, Fuyixue Wang3,4, J. Paul Hamilton5, Jingyuan E. Chen4,6, Ian H. Gotlib7, Mehdi Khalighi8, and Gary H. Glover2

1Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University, Beijing, China, 2Radiological Sciences Laboratory, Department of Radiology, Stanford University, Palo Alto, CA, United States, 3Harvard-MIT Health Sciences and Technology, MIT, Boston, MA, United States, 4A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, 5Center for Social and Affective Neuroscience, Linköping University, Linköping, Sweden, 6Department of Radiology, Harvard Medical School, Boston, MA, United States, 7Department of Psychology, Stanford University, Palo Alto, CA, United States, 8Applied Science Lab, GE Healthcare, Menlo Park, CA, United States

Our previous work has indicated a significant connection between dopamine release/binding and fMRI activation during reward processing in healthy controls (CTL), but not in major depressive disorder (MDD). It motivates us to explore whether there is a similar disrupting effect in the coupling of resting-state fMRI and baseline dopamine binding potential in MDD. By conducting a simultaneous [11C] Raclopride PET and fMRI study, we obtained significant correlations between striatal dopamine binding potential and VTA-striatum functional connectivity in CTL, but not in MDD, indicating that the decoupling of dopaminergic system and striatum may play a vital role in the pathophysiology of MDD.

209
15:09
Spatial-temporal dynamics of the visual cortex stiffness driven by a flashing checkerboard stimulus
Jose de Arcos1, Daniel Fovargue1, Radhouene Neji2, Sam Patz3, and Ralph Sinkus4

1School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom, 2Siemens Healthcare Limited, Frimley, United Kingdom, 3Department of Radiology, Brigham and Women’s Hospital, Boston, MA, United States, 4King's College London, London, United Kingdom

In this work we explore the relationship between localized stiffness changes in the visual cortex and the stimulus switching frequency using a novel functional MRE system (fMRE) capable of probing stiffness changes in the human brain driven by a 12Hz flashing checkerboard stimulus. We measured the mechanical response (fMRE) and BOLD response (fMRI) of the brain to slow (36.96s) switching speeds at timescale typical for classical fMRI experiments and compare the results to faster switching speeds (840ms) where the hemodynamic response (HDR) is entirely saturated, and hence cannot follow anymore the input signal. Combining this with our previous results we observe a characteristic behavior of stiffness changes: for switching speeds where the HDR is saturated the stiffness is higher during the OFF state, while we observe the opposite for switching speeds where the HDR can follow the stimulus. Both differed in baseline to control scans (OFF/OFF).

210
15:21
Simultaneous Measurement of functional MRI and MRS by Fast Non-water Suppressed Keyhole MR Spectroscopy Imaging
Xin Shen1, Pingyu Xia2, Masoumeh Dehghani ‎Moghadam3, Jamie Near3,4, Xiaopeng Zhou2, Mark Chiew5, Ulrike Dydak2,6, and Uzay Emir1,2

1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States, 2School of Health Sciences, Purdue University, West Lafayette, IN, United States, 3Department of Psychiatry, McGill University, Montreal, QC, Canada, 4Centre d'Imagerie Cérébrale, Douglas Mental Health University Institute, Montreal, QC, Canada, 5Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, United Kingdom, 6Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States

The non-water suppressed magnetic resonance spectroscopic imaging (MRSI) sequence with concentric k-space trajectory was proposed to measure functional MRI and MRSI signals simultaneously. A right-hand finger-tapping task was performed at 3T MRI scanner to test the simultaneous hemodynamic and neurochemical measurements at human primary motor cortex. The results showed a significant overlap between T2* and metabolite (glutamate) changes.

211
15:33
Imaging the Influence of Central Amygdala Neuronal Circuits on Nociception: a Combined Approach of Optogenetics and fMRI
Isabel Wank1, Pinelopi Pliota2, Silke Kreitz1, Wulf Haubensak2, and Andreas Hess1

1Institute of Pharmacology, University of Erlangen-Nuremberg, Erlangen, Germany, 2Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria

Optogenetics has proven to be a highly useful tool to delineate the function of distinct proteins. Here, this approach was combined with fMRI to activate in-vivo selectively two interacting, but supposedly opposing, neuronal circuits of the central lateral amygdala (CEl). A classical fMRI paradigm was chosen to study the influence of the activation of either PKCδ- or somatostatin-expressing neurons on central pain processing, and to identify involved brain networks or areas. PKCδ was found to act preferentially anti-nociceptive by controlling via thalamus higher-order brain regions. Somatostatin on the other hand was shown to interact very closely with brainstem regions, controlling in a “bottom-up”-fashion thalamus, limbic system and cortex.


Oral

B0 Field Management & Shimming

Room 710B
Monday 13:45 - 15:45
Moderators: William Handler & Irena Zivkovic
212
13:45
Design of a volume MRI coil by metalyzing 3D printing substrates by electroless and/or electroplating processes
Simon Auguste Lambert1, Tony Gerges2, Romain Delamea2, Mathilde Bigot1, Hugo Dorez1, Philippe Lombard2, Vicent Semet2, and Michel Cabrera2

1Univ. Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS, Lyon, France, 2Univ. Claude Bernard Lyon 1 (UCBL) Laboratoire AMPERE UMR 5005 CNRS, INSA, ECL, UCBL Campus LyonTech - La Doua, Lyon, France

Manufacturing compact, miniature devices required for small samples imaging is still challenging. Here we investigate the feasibility of metalyzing 3D printing subtrates to develop a volume coil dedicated to both small in-vitro / ex-vivo samples and in vivo mouse brain imaging. In order to validate the use of metalized 3D printed process to build MRI coil we build one reference Helmholtz coil made with copper tape wrapped around the coil mount and one with the same geometry using this new technology. First demonstration on bench and in imaging that copper metallization technology can be performed to build volume coil.

213
13:57
Nonlinearity and thermal effects in gradient chains: a cascade analysis based on current and field sensing
Jennifer Nussbaum1, Manuela B Rösler1, Benjamin E Dietrich1, and Klaas P Prüssmann1

1Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland

In MRI, many gradient field imperfections are linear and time-invariant to some extend and can be well modelled by gradient impulse response functions. However, time invariance is violated by thermal effects and linearity e.g. by the gradient amplifier. To isolate sources of model violations we split the gradient chain into a cascade, consisting of eddy current compensation, amplifier and coil. Coil and amplifier responses are disentangled by extending the field measurement by current monitoring. Linearity and time-invariance violations are analyzed by performing heating experiments and varying test pulses. We show that current monitoring enables independent treatment of nonlinear distortion and thermal effects and that gradient response nonlinearities can be resolved directly.

214
14:09
Initial imaging experience with a head gradient (MAGNUS) at 3.0T operating at 200 mT/m and 500 T/m/s
Thomas KF Foo1, Ek T Tan1, Mark Vermilyea1, Yihe Hua1, Eric Fiveland1, Joseph Piel1, Keith Park1, Justin Ricci1, Paul Thompson1, Gene Conte1, Matthew Tarasek1, Desmond TB Yeo1, David Lee2, J Kevin DeMarco3, Robert Shih3, Maureen Hood3,4, Heechin Chae5, and Vincent B Ho3,4

1GE Global Research, Niskayuna, NY, United States, 2GE Healthcare, Florence, SC, United States, 3Walter Reed National Military Medical Center, Bethesda, MD, United States, 4Uniformed Services University of the Health Sciences, Bethesda, MD, United States, 5Ft. Belvoir Community Hospital, Ft. Belvoir, VA, United States

Healthy volunteer subjects were safely imaged in a 3.0 T MRI system with an ultra-high performance head-gradient coil. The MAGNUS coil operates at 200 mT/m and 500 T/m/s, simultaneously on all 3-axes, and has a patient (head) bore diameter of 37-cm. Substantial reduction in pulse sequence TE, TR, and echo-planar imaging echo spacing was achieved with observable improvement in image quality. The design enabled the achievement of higher peripheral nerve stimulation thresholds compared to that for whole-body gradient coils.

215
14:21
A target-field shimming approach for improving the encoding performance of a lightweight Halbach magnet for portable brain MRI
Patrick C McDaniel1,2, Clarissa Zimmerman Cooley2, Jason P Stockmann2, and Lawrence L Wald2,3

1Massachusetts Institute of Technology, Cambridge, MA, United States, 2Athinoula A Martinos Center for Biomedical Imaging, Charleston, MA, United States, 3Harvard Medical School, Boston, MA, United States

Portable brain MRI scanners have the potential to increase the reach of diagnostic imaging but require relaxing constraints such as magnet homogeneity and gradient linearity or even elimination of gradient switching via a rotating magnet with built-in encoding fields.  Nonetheless, the encoding matrix must retain good conditioning and excessive signal bandwidth must be controlled. To address this, we developed and validated a permanent magnet shimming method for a lightweight Halbach-style brain imaging magnet and designed and constructed a pair of compact, head-only phase encoding gradients. We demonstrate these improvements in spatial encoding with head-sized phantom and in vivo brain images.

216
14:33
FAMASITO - FASTMAP Shim Tool Towards User-Friendly Single-Step B0 Homogenization
Karl Landheer1 and Christoph Juchem1,2

1Biomedical Engineering, Columbia University, New York, NY, United States, 2Radiology, Columbia University, New York, NY, United States

Fast, automatic shimming by mapping along projections (FASTMAP) is an elegant analytical method developed to quantify 3-dimensional first and second order spherical harmonic B0 shapes along six 1-dimensional column projections. The straightforward application of this theoretical concept to B0 shimming, however, neglects crucial aspects of sequence implementation and shim hardware, commonly necessitating multi-step iterative adjustments. Considering experimental imperfections of the employed B0 mapping and shim coil hardware, we demonstrate optimal single-step adjustment of first and second order terms (with potential <3% refinement of linear terms) in the anterior cingulate cortex, one of the most difficult-to-shim areas in the human brain.

217
14:45
Dynamic Optimization of Gradient Field Performance Using a Z-Gradient Array
Koray Ertan1,2, Soheil Taraghinia1, and Ergin Atalar1,2

1National Magnetic Resonance Research Center (UMRAM), Bilkent University, ANKARA, Turkey, 2Electrical and Electronic Engineering, Bilkent University, ANKARA, Turkey

Performance parameters of gradient coils such as size of the linearity volume, linearity error, inductance, power dissipation, gradient strength per unit current are determined at the design stage. On the contrary, array of gradient coils driven by independent amplifiers can enable optimization of this parameters. Therefore, optimal gradient performance can be realized depending on the sequence requirements and target volumes. Nine channel z-gradient array is used to optimize various performance parameters and to analyze the tradeoffs between them. Linear gradient profile generated by Z-gradient array hardware is used as readout gradient to demonstrate the feasibility of the hardware.

218
14:57
A 16-Channel RF Receive Array with Integrated B0-shim Capability for Anesthetized Monkey Whole Brain Imaging at 7T
Yang Gao1,2, Azma Mareyam2, Xiaotong Zhang1, Yi Sun3, Thomas Witzel2,4, Nicolas Arango5, Irene Kuang5, Jacob White5, Anna Wang Roe1, Lawrence Wald2,4, and Jason Stockmann2,4

1Interdisciplinary Institute of Neuroscience and Technology, Qiushi Academy for Advanced Studies, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China, 2Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 3MR Collaboration Northeast Asia, Siemens Healthcare, Hangzhou, China, 4Harvard Medical School, Boston, MA, United States, 5Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States

To mitigate signal dropout in EPI images due to local B0 inhomogeneities inevitably caused by craniotomies and chamber implantations needed for multimodal studies, we designed a custom 16-channel tight-fit receive array, with each receive element integrated with DC pathway for multi-coil B0 shimming. The feasibility of constructing high-density receive array (5cm diameter loop elements) integrated with B0-Shim has been demonstrated. With DC-enabled higher-order local B0 shimming, obvious improvement in recovering local signal drop out and image distortion around brain surgery region, implying its promising application in high-resolution multi-modal monkey neuroimaging.

219
15:09
Dynamic Multi-Coil Technique (DYNAMITE) MRI on Human Brain
Christoph Juchem1, Michael Mullen2, Chathura Kumaragamage3, Lance DelaBarre2, Gregor Adriany2, Peter B Brown3, Scott McIntyre3, Terence W Nixon3, Michael Garwood2, and Robin A de Graaf3

1Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY, United States, 2Department of Radiology, Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, MN, United States, 3Department of Radiology and Biomedical Imaging, Magnetic Resonance Resesarch Center (MRRC), Yale University, New Haven, CT, United States

To date, spatial encoding for human MRI is based on linear X, Y and Z field gradients generated by dedicated X, Y and Z gradient coils. We recently introduced the Dynamic Multi-Coil Technique (DYNAMITE) for B0 magnetic field modeling and demonstrated DYNAMITE MRI in a miniaturized setup. In this study we report the first realization of multi-slice DYNAMITE MRI of the in vivo human brain in which all gradient fields are purely DYNAMITE-based. The obtained image fidelity is comparable to MRI with conventional gradient coils, paving the way for full-fledged human DYNAMITE MRI systems.

220
15:21
Integrated AC/DC coil and dipole Tx array for 7T MRI of the spinal cord
Nibardo Lopez Rios1, Ryan Topfer2, Alexandru Foias2, Axel Guittonneau2,3, Kyle M. Gilbert4, Ravi S. Menon4,5, Lawrence L. Wald6,7,8, Jason P. Stockmann6,7, and Julien Cohen-Adad2,9

1NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada, 2Electrical Engineering, Ecole Polytechnique de Montreal, Montreal, QC, Canada, 3École Normale Supérieure de Lyon, Lyon, France, 4Centre for Functional and Metabolic Mapping, The University of Western Ontario, London, ON, Canada, 5Department of Medical Biophysics, The University of Western Ontario, London, ON, Canada, 6Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 7Harvard Medical School, Boston, MA, United States, 8Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States, 9Functional Neuroimaging Unit, CRIUGM, University of Montreal, Montreal, QC, Canada

Imaging the spinal cord is a never-ending challenge, especially when venturing to ultra-high fields. We propose a novel coil design for spinal cord 7T MRI, which combines state-of-the-art transmit and receive technologies. The transmit coil is a 3-dipole array, allowing homogeneous B1 field with parallel excitation. The receive part consists of a 15-channel AC/DC coil that can achieve both high sensitivity and local B0 shimming, including real-time shimming to compensate for respiratory-induced field variations. The design can achieve 32% reduction of static field inhomogeneities and 27% reduction in temporal field variance, opening the door to exciting EPI and spectroscopy applications. 

221
15:33
B-0 shimming of the liver using a local array of shim coils in the presence of respiratory motion at 7T
Lieke van den Wildenberg1, Quincy van Houtum1, Wybe J. M. van der Kemp1, Catalina S. Arteaga de Castro1, Sahar Nassirpour2, Paul Chang2, and Dennis W. J. Klomp1

1Center for Image Sciences, UMC Utrecht, Utrecht, Netherlands, 2MR Shim GmbH, Reutlingen, Germany

Inhomogeneity of the magnetic field (B0) in the human body, for instance caused by physiological motion (e.g. breathing), can lead to artifacts. Static second order magnetic field shimming even in the absence of breathing cannot provide a uniform magnetic field in large organs such as the liver, particularly at ultra-high field throughout the breathing cycle. We show that in conjunction with static second order shimming, local arrays of shim coils can substantially improve the magnetic field uniformity in the liver at different breathing states. 


Member-Initiated Symposium

MRI of the Placenta & Fetus: Challenges & Opportunities

Organizers: Oliver Wieben, Katarina Steding Ehrenborg
Room 516AB
Monday 13:45 - 15:45
Moderators: Jana Hutter & Erik Hedström
(no CME credit)
13:45
Quantification in Fetal & Placental MRI: Clinical Motivation
Ellen Grant1

1Boston Children's Hospital

14:09
Quantification in fetal & Placental MRI: Towards Clinical Applications
Penny Gowland1

1SPMIC, University of Nottingham, Nottingham, United Kingdom

14:33
Non-Human Primate Models of Pregnancy in Placental & Fetal MRI: Opportunities & Challenges
Matthias Christian Schabel1

1Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States

14:57
Automating Motion Compensation in 3T Fetal Brain Imaging: Localize, Align & Reconstruct
Lucilio Cordero-Grande1

1King's College London, London, United Kingdom

15:21
Motion Correction in Fetal Cardiovascular MRI
Christopher Macgowan1

1University of Toronto / Hospital for Sick Children


Member-Initiated Symposium

Open Source Initiative for Perfusion Imaging

Organizers: Steven Sourbron, Laura Bell
Room 513A-C
Monday 13:45 - 15:45
(no CME credit)
13:45
Introduction to the Perfusion Open-Source Initiative
Andriy Fedorov1

1Brigham Women's Hospital, Boston, MA, United States

14:00
Building Software for Reproducible Research: Lessons from the BART Project
Martin Uecker1

1University Medical Center Göttingen, Germany

14:20
Welcome to the Jungle: Open-Source Software for DCE & DSC
Charlotte Debus

14:30
Standardized Open-Source Image Analysis: Can We Avoid Confusion but Focus on Perfusion?
Henk-Jan Mutsaerts1

1Amsterdam University Medical Center, Amsterdam, Netherlands

14:45
Best Practices in DRO Development
Daniel Barboriak

14:50
Digital Reference Objects for DCE-MRI: Sources & Directions
Daniel Barboriak

14:55
An Anthropomorphic Digital Breast Phantom for Simulation & Analysis of MRI Techniques: Implementation for dynamic contrast-enhanced MRI
Leah Henze Bancroft

15:00
A Population-Based Digital Reference Object (DRO) for Optimizing Dynamic Susceptibility Contrast (DSC) MRI Methods for clinical trials
Natenael B Semmineh1

1imaging research, Barrow Neurological Institute, Phoenix, AZ, United States

15:10
DICOM Parametric Maps: A Common Language for Perfusion Software
Ina Kompan

15:30
Break & Meet The Teachers


Study Group Business Meeting

MR Elastography Study Group Business Meeting

Room 511D
Monday 14:45 - 15:45
(no CME credit)

Digital Poster: Cardiovascular
Exhibition Hall
Monday 16:00 - 17:00
(no CME credit)
Study Group Business Meeting

MR of Cancer Study Group Business Meeting

Room 511A
Monday 16:00 - 17:00
(no CME credit)

Study Group Business Meeting

Psychiatric MR Spectroscopy & Imaging Study Group Business Meeting

Room 511D
Monday 16:00 - 17:00
(no CME credit)

Weekday Course

Diverse Perspectives on Imaging-Based Diagnosis of HCC

Organizers: Mustafa Shadi Bashir, Utaroh Motosugi
Room 516C-E
Monday 16:00 - 18:00
Moderators: Johannes Heverhagen & Mustafa Bashir
16:00
Hepatologist's Perspective
Andrew Muir1

1Duke University Medical Center, Durham, NC, United States

Hepatocellular carcinoma (HCC) is a leading cause of cancer mortality worldwide.  The key to preventing mortality is to diagnose HCC at an early stage when curative therapies can be offered.  Candidacy for hepatic resection or liver transplantation is an early decision.  Embolization and ablation procedures are important therapeutic modalities.  Patients at high risk for HCC are recommended to participate in surveillance programs.  Effective imaging is critical to patients with chronic liver disease given their risk of HCC.  Imaging allows early identification and diagnosis with ongoing monitoring capabilities, and patients are given the best option for pursuit of cure from HCC.

16:30
LI-RADS
Kathryn Fowler1

1University of California, San Diego, La Jolla, CA, United States

Review worldwide approaches to HCC diagnosis, highlighting similarities and differences in algorithms. Provide an overview of updates to LI-RADS/AASLD, updates to literature, and highlight future directions based on current gaps in knowledge. 

16:55
Self Assessment Module (SAM)

17:00
European Guidelines
Luigi Grazioli1

1University of Brescia, Italy

 Hepatocellular carcinoma surveillance aims to reduce disease-related mortality. High risk patients who were enrolled into a surveillance programme were diagnosed at an earlier stage, received potential curative therapies more frequently, and had better overall survival than did unenrolled patients. 

17:30
Asian Guidelines
Keitaro Sofue1

1Kobe University Graduate School of Medicine, Kobe, Japan

Diagnostic imaging systems have critical role in the surveillance and diagnose hepatocellular carcinoma (HCC) in early stages, resulting in improvement of the prognosis of patients with HCC.

Several scientific organizations have proposed imaging-based diagnostic systems of HCC, and they vary between geographic areas caused by different target populations, resources, and treatment practices.

I will review the current imaging-based diagnostic systems especially in Asian, and present its' characteristics with some case presentations.


18:00
Adjournment


Weekday Course

Functional & Dynamic MR Imaging of Peripheral Joints & Spine

Organizers: Riccardo Lattanzi, Jung-Ah Choi, Miika Nieminen, Jan Fritz, Edwin Oei
Room 511BCEF
Monday 16:00 - 18:00
Moderators: Jan Fritz & Valentina Mazzoli
16:00
Imaging Biomechanics of Whole Joints
David Wilson1

1Orthopaedics and Centre for Hip Health and Mobility, University of British Columbia, Canada

The purpose of this presentation is to explain why studying whole joint biomechanics is important, outline the benefits and limitations of studying whole joint biomechanics using MRI, and highlight some new MR approaches that have potential for substantial improvements in studying joint biomechanics.

16:30
Prospective Motion Correction During Loading
Thomas Lange1

1Dept. of Radiology, Medical Physics, Medical Center - University of Freiburg, Freiburg, Germany

Knee MRI with in situ loading is strongly hampered by subject motion. However, the resulting artifacts can be efficiently suppressed by prospective motion correction. The functional principle of prospective motion correction based on optical tracking is explained and its use for knee MRI with in situ loading is demonstrated. Challenges, limitations and pitfalls of the technique are addressed. Results of anatomical and relaxometric cartilage MRI with prospective motion correction are presented. Non-rigid body motion and tracking marker fixation are the main limitations for most orthopedic applications. The ease of implementation and the correction efficacy of prospective motion correction are sequence-dependent.

17:00
Dynamic MRI of Joints: Technical Factors and Clinical Applications
Valentina Mazzoli1

1Radiology, Stanford University, CA, United States

while static MRI is widely used clinically for the assessment of several joints, it often fails to provide information on their biomechanical and functional status. On the other hand, dynamic MRI allows to gather information on the normal and impaired musculoskeletal function during motion but is technically more challenging. This presentation will cover some of the technical factors needed to perform and analyze a dynamic MRI experiment of the joints, and will highlight some clinical and research applications where dynamic MRI can add useful information to conventional static imaging.

17:30
Clinical Application: Loaded Imaging of the Spine & Peripheral Joints
Garry Gold1

1Radiology, Stanford, Stanford, CA, United States

18:00
Adjournment


Weekday Course

MR Physics & Techniques for Clinicians

Organizers: Bernd Jung, Marcus Alley, Dong-Hyun Kim
Room 710A
Monday 16:00 - 18:00
Moderators: Yoonho Nam & Marcus Alley
16:00
Spin Gymnastics
Frank Korosec1

1University of Wisconsin - Madison, United States

This educational lecture will provide a general overview of the basic physics of MRI. A broad range of topics will be covered, including magnetization and signal generation, relaxation of magnetization, the spin echo phenomenon, spatial encoding of signal, and a very brief introduction to the concept of k-space. Several of the topics will be introduced in this lecture and will be further elucidated by other presenters in this course.

17:30
Image Quality
Rafael O'Halloran1

1United States

In this educational talk we discuss how MRI acquisition parameters affect aspects of image quality using the concept of k-space.

18:00
Adjournment


Power Pitch

Pitch: Diffusion MRI: Acquisition, Reconstruction & Artefact Correction

Power Pitch Theater A - Exhibition Hall
Monday
Pitches: 16:00 - 17:00
Posters: 17:00 - 18:00
Moderators: Charles Hing-Chiu Chang & Zhe Zhang
(no CME credit)
222
Pitch: 16:00
Poster: 17:00
Plasma 1
A GRANDIOSE sequence to time-lock BOLD and diffusion-weighted fMRI contrasts in humans using ultra-strong gradients and spirals
Suryanarayana Umesh Rudrapatna1, Lars Mueller1, Melissa Emily Wright1, Derek K Jones1, and Richard G Wise1

1CUBRIC, School of Psychology, Cardiff University, Cardiff, United Kingdom

Diffusion-weighted fMRI (dfMRI) has been suggested to provide more direct and specific correlates to neuronal activation than BOLD fMRI. However, its underpinnings are debated. A sequence that captures BOLD and dfMRI contrasts simultaneously can play a vital role in elucidating the dfMRI contrast mechanisms. Hence, we developed a sequence that leverages the ultra-strong gradients for diffusion-weighting and spiral-in and spiral-out trajectories to acquire BOLD and dfMRI contrasts near-simultaneously. We demonstrate its functionality using visual stimulation in humans. This novel sequence enables a direct comparison between BOLD and dfMRI contrasts and offers new opportunities to improve our understanding of these contrasts.

223
Pitch: 16:00
Poster: 17:00
Plasma 2
Is spherical diffusion encoding rotation invariant? An investigation of diffusion time-dependence in the healthy brain
Filip Szczepankiewicz1,2, Samo Lasic3, Markus Nilsson4, Henrik Lundell5, Carl-Fredrik Westin1,2, and Daniel Topgaard6

1Radiology, Brigham and Women's Hospital, Boston, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Random Walk Imaging AB, Lund, Sweden, 4Clinical Sciences Lund, Lund University, Lund, Sweden, 55. Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark, 6Physical Chemistry, Lund University, Lund, Sweden

Recent advances in diffusion weighted MRI have reignited interest in spherical (or isotropic) diffusion encoding. For such encoding to reach high efficiency (minimal echo time), the gradient waveforms have irregular shapes, by design. As such, they lack a well-defined diffusion time and can even be spectrally anisotropic. Most analysis methods based on such encoding assume that diffusion is multi-Gaussian, i.e., that the diffusion is not time-dependent. Since this is a central assumption, we investigate if spherical diffusion encoding is indeed rotation invariant, or if the diffusion time anisotropy has a discernible effect on the diffusion weighted signal in healthy brain.

224
Pitch: 16:00
Poster: 17:00
Plasma 3
Application of an Extended Stretched-Exponential Model for Morphometric Analysis of Accelerated Diffusion-weighted 129Xe MRI of the Rat Lung
Alexei Ouriadov1, Matthew S Fox2, Andras A Lindenmaier3,4, Elaine Stirrat3, Grace Parraga1,5,6, and Giles Santyr3,4

1Robarts Research Institute, London, ON, Canada, 2Lawson Imaging, Lawson Health Research Institute, London, ON, Canada, 3Translational Medicine Program, Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, Toronto, ON, Canada, 4Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada, 5Department of Medical Biophysics, Western University, London, ON, Canada, 6Division of Respirology, Department of Medicine, Western University, London, ON, Canada

Hyperpolarized 129Xe pulmonary MRI is poised for clinical translation due in part to the clinical-relevance of 129Xe MRI biomarkers of lung disease.  A rapid multi-b diffusion-weighted 129Xe MRI requires for clinical morphometry due to the challenges in acquiring a fully-sampled dataset during the relatively short 10-16sec breath-holds. Therefore, in this proof-of-concept evaluation, our objective was to measure morphometry estimates in a small group of control-rats as well as rats with early stage radiation-induced-lung-injury, and compare the stretched-exponential-model based morphometry estimates for three different cases: 1) fully-sampled k-space 2) 85% retrospectively under-sampled k-space, (acceleration factor (AF)=7), and 3) 90% retrospectively under-sampled (AF=10) k-space.

225
Pitch: 16:00
Poster: 17:00
Plasma 4
SPatiotemporal ENcoding (SPEN) at ultra-high fields: Applications to high resolution (<100 µm isotropic) in vivo mouse brain DTI
Maxime Yon1, Qingjia Bao1, Rafael Henriques2, Noam Shemesh2, and Lucio Frydman1

1Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel, 2Champalimaud Centre for the Unknown, Lisbon, Portugal

SPEN can be a valuable alternative to Spin Echo EPI, especially at very high fields where sensitivity is maximized but magnetic field susceptibility artifacts become important. This work presents a new Paravision® 6 software package capable of acquiring and processing SPEN data, incorporating single/multishot acquisitions, motion correction, image zooming and multiple contrast possibilities such as CEST, diffusion or multi-echo acquisition. The power of this method is exemplified with in vivo 2D and 3D diffusion tensor imaging (DTI) studies on whole and zoomed mouse brain regions, acquired at 15.2T utilizing a cryoprobe and reaching isotropic resolution of 75 µm.

226
Pitch: 16:00
Poster: 17:00
Plasma 5
Storing phase information in the longitudinal direction: Experimental verification of double diffusion encoding with stimulated echoes applied to closed pores
Kerstin Demberg1,2, Frederik Bernd Laun3, Peter Bachert1, and Tristan Anselm Kuder1

1Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Faculty of Physics and Astronomy, Heidelberg University, Heidelberg, Germany, 3Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany

When applying double diffusion encoding (DDE) to arbitrarily shaped closed pores, non-vanishing imaginary parts in the diffusion signal arise, which allow determining the average shape of the pores in the considered volume element. Key limitations in such experiments are the available gradient strength and reaching the diffusion long-time limit restricted by T2 decay. When incorporating stimulated echoes into DDE-sequences, the slower T1 relaxation can be exploited to reach the long-time limit in larger pores demanding lower gradient strengths. We present experimental verification that phase information can be stored in longitudinal magnetization direction thus preserving complex signals under application of stimulated echoes.

227
Pitch: 16:00
Poster: 17:00
Plasma 6
Diffusion acquisition methods for unfixed ex vivo neonatal brain scan at 7T: sequence optimisation and preliminary experiments
Wenchuan Wu1, Jerome Sallet1,2, Rogier B Mars1, Benjamin C Tendler1, Matteo Bastiani1,3, Sebastian W Rieger1, Daniel Papp1, Jacques-Donald Tournier4,5, Joseph V Hajnal4,5, and Karla L Miller1

1Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, United Kingdom, 2Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom, 3Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom, 4Centre for the Developing Brain, King's College London, London, United Kingdom, 5Biomedical Engineering Department, King's College London, London, United Kingdom

In this work we present preliminary investigations into the use of diffusion-weighted steady state free procession (DW-SSFP) sequences and conventional diffusion-weighted spin-echo (DW-SE) sequences for unfixed neonate brains. We conduct an exploratory experiment to demonstrate the feasibility of existing dMRI methods on an unfixed porcine brain. We then propose a framework to match DW-SE and DW-SSFP contrast in a way that predicts optimal performance of each, in order to compare between methods.

228
Pitch: 16:00
Poster: 17:00
Plasma 7
Towards robust free-breathing cardiac DTI
Stephen G Jermy1,2, Aaron T Hess3, Ntobeko A B Ntusi4,5, Ernesta M Meintjes1,2, and Elizabeth M Tunnicliffe3

1MRC/UCT Medical Imaging Research Unit, University of Cape Town, Cape Town, South Africa, 2Cape Universities Body Imaging Centre (CUBIC-UCT), University of Cape Town, Cape Town, South Africa, 3Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, United Kingdom, 4Department of Medicine, University of Cape Town, Cape Town, South Africa, 5Hatter Institute for Cardiovascular Research in Africa, University of Cape Town, Cape Town, South Africa

A prospective respiratory motion correction control system, capable of performing of slice tracking, was implemented in a spin echo diffusion weighted sequence to perform free-breathing acquisitions. The performance of the motion correction control system was compared against common respiratory motion compensation techniques, namely breath-holds, respiratory gating, and standard slice tracking. The values of all the free-breathing techniques varied from the breath-hold data, however, the motion correction control system produced very consistent results. The slice tracking methods were able to significantly reduce the acquisition time (by 50%), compared to the respiratory gating technique. 

229
Pitch: 16:00
Poster: 17:00
Plasma 8
Model based joint B0 and image estimation framework for dynamic field mapping and signal pile-up correction in prostate diffusion MRI
Muhammad Usman1, Antonis Matakos2, Lebina Kakkar1, Simon Arridge1, and David Atkinson1

1University College London, London, United Kingdom, 2Canon Medical Research USA, Cleveland, OH, United States

Prostate diffusion MRI is recognized as a potential biomarker for tumour detection but currently it is unusable in some patients due to significant distortions. We proposed a novel model based joint image and B0 reconstruction framework that can correct these distortions by using data acquired from opposite phase encoding gradient directions. Using sampling time shift between the two acquisitions, the proposed method is robust against any dynamic changes in the off resonance effects in the prostate-rectal air region.  

230
Pitch: 16:00
Poster: 17:00
Plasma 9
Self-calibrated and Collaborative Propeller-EPI Reconstruction (SCOPER) for High-Quality Diffusion-Tensor Imaging
Xiaoxi Liu1, Di Cui1, Erpeng Dai2, Edward S. Hui1,3, Queenie Chan4, and Hing-Chiu Chang1

1Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong, China, 2Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, 3The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China, 4Philips Healthcare, Hong Kong, China

Propeller-EPI is a self-navigated multi-shot technique for high-resolution diffusion-tensor imaging. However, corrections for 2D Nyquist ghost and distortion for each blade data are necessary to obtain high-quality image. In this study, we aim to develop a self-calibrated and collaborative Propeller-EPI reconstruction (SCOPER) framework that can 1) allows the estimation of phase errors and off-resonance map from the blade data, and 2) collaboratively reconstruct fully-corrected Propeller-EPI image from all blade data and the thereof. Our results demonstrated that SCOPER shows improved SNR performance, compared with conventional Propeller-EPI reconstruction pipelines.

231
Pitch: 16:00
Poster: 17:00
Plasma 10
Simultaneous Reconstruction of Multiple b-Values DWI using a Joint Convolutional Neural Network
Chengyan Wang1, Yucheng Liang2, Yuan Wu1, Danni Yang2, and Yiping P. Du1

1Institute for Medical Imaging Technology (IMIT), School of Biomedical Engineering, Shanghai Jiao Tong university, Shanghai, China, 2Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States

This study presented a joint convolutional neural network (CNN) architecture for the reconstruction of multiple b-values diffusion-weighted (DW) images simultaneously. The proposed joint-net is able to extract high-level anatomical correlations among multi-contrast images and correct misalignment between images by adding a spatial transformation layer. Experimental results show that the proposed algorithm outperforms single image reconstruction network and compressed sensing algorithm with improved image quality. The training process of the joint-net is much more efficient compared to individual training for each b-value image. Besides, combination of data consistency and the joint-net enables precise characterization of brain tumor in a patient study.

232
Pitch: 16:00
Poster: 17:00
Plasma 11
Improved gSlider Reconstruction for Isotropic High-Resolution DTI Using A Model-Based Method and Virtual Coil Concept
Simin Liu1, Erpeng Dai1,2, Zijing Dong1,3,4, and Hua Guo1

1Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, 2Department of Radiology, Stanford University, Stanford, CA, United States, 3A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 4Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA, United States

Recently, generalized SLIce Dithered Enhanced Resolution (gSlider) has been proposed as a new acquisition strategy for isotropic high-resolution DTI. In this study, to further boost the SNR performance and reconstruction accuracy, the model-based DTI reconstruction method was merged into the gSlider reconstruction procedure. Moreover, virtual coil (VC) concept was also integrated into the proposed method to further improve the SNR of gSlider reconstruction. Compared with conventional GRAPPA, the superiority of the model-based method has been demonstrated by in vivo results, especially when in combination with the virtual coil concept.

233
Pitch: 16:00
Poster: 17:00
Plasma 12
SMS-MUSSELS: A Navigator-free Reconstruction for Slice-accelerated Multi-shot Diffusion Imaging
Merry Mani1, Mathews Jacob1, Graeme McKinnon2, Baolian Yang2, Brian Rutt3, Adam Kerr3, and Vincent Magnotta1

1University of Iowa, Iowa City, IA, United States, 2GE Healthcare, Milwaukee, WI, United States, 3Stanford University, Stanford, CA, United States

Multi-shot diffusion-weighted (msDW) imaging schemes can improve the spatial resolution of DWIs. However, the multi-shot readout spans multiple TRs which reduce the time efficiency of msDWI. Hence the practical utility of multi-shot methods for high angular resolution imaging for fiber tracking purposes currently remains limited. To improve the time efficiency of msDWI, SMS acceleration can be employed. However, the DWIs from SMS-accelerated msDW acquisition will exhibit severe artifacts due to slice aliasing and inter-shot phase inconsistencies arising from the msDW encoding.  We present a novel navigator-free reconstruction method to simultaneously slice unfold and jointly recover multi-shot diffusion data from an SMS-accelerated msDW acquisition. The method is shown to effectively reconstruct 4-shot DW data accelerated at a multi-band factor of 3.

234
Pitch: 16:00
Poster: 17:00
Plasma 13
A nonlinear model for DTI reconstruction with locally low-rank regularization
Yuxin Hu1, Qiyuan Tian2, Grant Yang1, Jennifer A McNab3, Bruce Daniel3,4, and Brian Hargreaves1,3,4

1Department of Electrical Engineering, Stanford University, Stanford, CA, United States, 2Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States, 3Department of Radiology, Stanford University, Stanford, CA, United States, 4Department of Bioengineering, Stanford University, Stanford, CA, United States

We developed a nonlinear model with simultaneous phase and magnitude updates for iterative multi-shot DWI reconstruction. In addition, locally low-rank regularization along the diffusion encoding direction was included in the proposed model to utilize angular correlation for DTI reconstruction. In-vivo high-resolution and high b-value images have been acquired to validate the proposed method and the proposed method significantly reduces image noise.

235
Pitch: 16:00
Poster: 17:00
Plasma 14
ZEBRA – from rich-multi-dimensional data to anatomical profiles
Jana Hutter1,2, Jonathan O'Muircheartaigh1,2, Paddy Slator3, Daan Christiaens1,2, Sophie Arulkumaran2, Lucilio Cordero Grande1,2, Rui Pedro A G Teixeira1, Anthony N Price1,2, J-Donald Tournier1,2, and Joseph V Hajnal1,2

1Biomedical Engineering Department, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 2Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 3University College London, London, United Kingdom

An efficient joint multi-parametric diffusion-relaxometry MRI acquisition, ZEBRA, is presented. Improvements to optimize the joint sampling in several dimensions include logarithmic TI sampling, superblock strategies and globally and locally optimized gradient schemes. These are introduced together with a proposed whole-brain protocol (resolution 2.5mm isotropic). The data is analysed by an assumption free clustering step – designed to extract tissue information and anatomical profiles directly from the signal. Depiction of several clusters – including the deep grey matter and cerebellar substructures - illustrate the richness of the obtained data.

236
Pitch: 16:00
Poster: 17:00
Plasma 15
In-vivo diffusion-fMRI using Incomplete Initial Nutation Diffusion Imaging (INDI)
Daniel Nunes1 and Noam Shemesh2

1Champalimaud Research, Champalimaud Centre for the Unkown, Lisbon, Portugal, 2Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal

Diffusion functional-MRI (dfMRI) is thought to capture microstructural changes associated with neural activity. The water apparent diffusion coefficient decrease observed upon neuronal activity is hypothesized to be cell-swelling dependent. Yet, one of the confounding factors for dfMRI is that zero and nonzero b-values need to be acquired to deliver accurate changes in diffusivity and those images are typically separated by at least one repetition time. Incomplete initial Nutation Diffusion Imaging (INDI) was proposed as a method to acquire two images with different diffusion-weighting with separation of <50ms. Here, we performed INDI-fMRI experiments to report mean diffusivity changes using forepaw-stimulated rats.  


Power Pitch

Pitch: Frontiers of Neuro Techniques

Power Pitch Theater B - Exhibition Hall
Monday
Pitches: 16:00 - 17:00
Posters: 17:00 - 18:00
Moderators: Muge Karaman & Joshua Trzasko
(no CME credit)
237
Pitch: 16:00
Poster: 17:00
Plasma 16
Robustness of PSIR segmentation and R1 mapping at 7T: a travelling head study
Olivier E. Mougin1, William T Clarke2, Ian Driver3, Catarina Rua4, Andrew T Morgan5, Susan Francis1, Keith Muir5, Adrian Carpenter4, Chris Rodgers4, Richard Wise3, David Porter5, Stuart Clare2, and Richard E. Bowtell1

1Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 2Nuffield Department of Clinical Neurosciences, University of Oxford, Wellcome Centre for Integrative Neuroimaging (FMRIB), Oxford, United Kingdom, 3School of Psychology, Cardiff University, Cardiff University Brain Research Imaging Centre, Cardiff, United Kingdom, 4Department of Clinical Neurosciences, University of Cambridge, Wolfson Brain Imaging Centre, Cambridge, United Kingdom, 5University of Glasgow, Imaging Centre of Excellence, Glasgow, United Kingdom

Ultra-high magnetic field (7T) MRI scanners can provide high spatial resolution images and excellent contrast for classifying brain tissue, but robustness of tissue segmentation and R1 quantification across sites is key for the implementation of multi-site studies. Here, we present a subset of the main UK7T travelling-head study, focusing on harmonized T1-weighted images (0.7mm3 isotropic resolution) acquired on six subjects across three 7T sites, with five repeats at one site. The aim of this study is to assess the harmonisation and robustness of the MP2RAGE sequence and PSIR reconstruction across sites, by focusing on segmentation reproducibility and T1 estimation. 

238
Pitch: 16:00
Poster: 17:00
Plasma 17
Separation of Cardiac- and Respiratory-driven CSF Motions under Free Breathing based on Realtime Phase Contrast Imaging and S-Transform
Kagayaki Kuroda1,2,3, Tetsuya Tokushima3, Satoshi Yatsushiro1,4, Nao Kajiwara5, Tomohiko Horie5, Hideki Atsumi6, and Mitsumori Matsumae6

1Department of Human and Information Science, School of Into Science and Technology, Tokai University, Hiratsuka, Japan, 2Center for Frontier Medical Engieering, Chiba University, Chiba, Japan, 3Course of Electrical and Electronic Engineering, Graduate School of Engineering, Tokai University, Hiratsuka, Japan, 4BioSim Research Center, BioView Inc., Tokyo, Japan, 5Department of Radioligy, Tokai University Hospital, Isehara, Japan, 6Department of Neurosurgery, Tokai University School of Medicine, Isehara, Japan

To separately visualize respiratory- and cardiac-driven motions of intracranial cerebrospinal fluid (CSF) under free breathing, CSF velocity distribution in 6 healthy volunteers and 3 hydrocephalus patients were acquired with asynchronous real time phase contrast (PC). Spectrograms of CSF velocity waveform as well as ECG and respiratory signals were obtained by Stockwell Transform (ST), in which the length of a Gaussian window length was adaptively changed according to the time-varying frequency of the signals. Comparison with the conventional short-term Fourier transform (STFT) with fixed length window revealed that separation of respiratory and cardiac components of CSF motion was possible with ST.

239
Pitch: 16:00
Poster: 17:00
Plasma 18
CVR-MRICloud: an automated online tool for the processing of cerebrovascular reactivity (CVR) MRI data
Zachary Baker1, Yang Li1, Peiying Liu1, Yue Li2, Michael I. Miller3, Susumu Mori1,4, and Hanzhang Lu1

1Department of Radiology, Johns Hopkins School of Medicine, Baltimore, MD, United States, 2AnatomyWorks LLC, Baltimore, MD, United States, 3Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States, 4Kennedy Krieger Institute, Baltimore, MD, United States

Cerebrovascular reactivity (CVR) has recently become a focus for many labs. However, CVR calculation has always required at least some degree of manual intervention. Therefore, our lab has developed CVR-MRICloud, a free, online, fully automated CVR processing pipeline. Our pipeline returns CVR maps, relative bolus arrival time maps, and region-of-interest CVR values. The maps are given in their original space as well as standardized MNI space. The pipeline has been shown to procure results corresponding to accepted CVR processing techniques that rely on manual intervention. This pipeline has potential to streamline other researchers’ acquisition of CVR values in subjects.

240
Pitch: 16:00
Poster: 17:00
Plasma 19
Comparing neural networks for synthesizing FLAIR images from T1WI and T2WI
Takashi Abe1, Yuki Matsumoto1, Yuki Kanazawa1, Yoichi Otomi1, Maki Otomo1, Moriaki Yamanaka1, Mihoko Kondo1, Saya Matsuzaki1, Ariunbold Gankhuyag1, Enkhamgalan Dolgorsuren 1, Oyundari Gonchigsuren1, and Masafumi Harada1

1Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan

  1. We checked the performances of different convolutional encoder decoder (CED), one of the neural networks when synthesizing FLAIR using T1WI and T2WI. With the shallow CED, the resolution was good but the contrast was poor, and when the CED became deeper, contrast became better, but the resolution became worse. Next we also added “skip-connection” to CED, but the image quality was not improved with the Inception(GoogLeNet)-like parallel skip-connection, and the image quality improved with the ResNet-like serial skip-connection; that was a mixture of shallow and deep CED, and resembled the structure of U-net.

241
Pitch: 16:00
Poster: 17:00
Plasma 20
Performance comparison of compressed sensing algorithms for accelerating T1ρ mapping of Human Brain
Rajiv G Menon1, Marcelo VW Zibetti1, and Ravinder R Regatte1

1Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, United States

3D-T mapping sequences are useful MRI methods in various neuropathologies but its data acquisition requires long scan times. We compared the performance of 5 compressive sensing (CS) algorithms with acceleration factors (AF) up to 10. We evaluated image quality and T estimation errors as a function of AF. Six healthy volunteers were recruited and they underwent T imaging of the whole brain with full Cartesian acquisition. Assessment of image reconstruction and T estimation errors in this study show that the CS method using spatial and temporal finite differences as a regularization function performs the best for accelerating T quantification in the brain.

242
Pitch: 16:00
Poster: 17:00
Plasma 21
Enhancement and Evaluation of the White Matter Connectome of the IIT Human Brain Atlas
Xiaoxiao Qi1, Shengwei Zhang1, and Konstantinos Arfanakis1

1Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, United States

In the IIT Human Brain Atlas project we have developed anatomical as well as state-of-the-art diffusion tensor and high angular resolution diffusion imaging (HARDI) templates, probabilistic gray matter labels, and probabilistic connectivity-based white matter labels for the young adult brain. The purpose of this work was two-fold: a) to enhance the white matter connectome of the IIT Human Brain Atlas through an improved tractography strategy, appropriate filtering of streamlines, and use of more precisely defined gray matter labels, and b) to evaluate how representative the new connectome is of young adult participants of the Human Connectome Project.

243
Pitch: 16:00
Poster: 17:00
Plasma 22
Single-shot Diffusion-weighted Spiral Imaging in the Brain on a Clinical Scanner
Peter Börnert1,2, Holger Eggers1, Kay Nehrke1, Peter Koken1, Jan Groen3, Suthambhara Nagaraj3, Johan van den Brink3, and Silke Hey3

1Tomographic Imaging Systems, Philips Research, Hamburg, Germany, 2Radiology, LUMC, Leiden, Netherlands, 3MRI, Philips Healthcare, Best, Netherlands

Single-shot diffusion-weighted imaging is predominantly performed with echo planar imaging today. Spiral imaging allows shorter echo times and thus promises higher signal-to-noise ratio, but is sensitive to various system imperfections. While previous work resorted to using a field camera for this reason, this work demonstrates the feasibility of single-shot diffusion-weighted spiral imaging in the brain on a clinical scanner without extra hardware for field monitoring. Good image quality was generally achieved in volunteers for different diffusion gradient directions up to high b-values using the demand trajectory for gridding, parallel imaging for acceleration, and static main field inhomogeneity mapping for deblurring.

244
Pitch: 16:00
Poster: 17:00
Plasma 23
The developing Human Connectome Project (dHCP): fetal acquisition protocol
Anthony N Price1,2, Lucilio Cordero-Grande1,2, Emer Hughes1, Suzanne Hiscocks1, Elaine Green1, Laura McCabe1, Jana Hutter1, Giulio Ferrazzi1, Maria Deprez2, Thomas Roberts2, Daan Christiaens2, Eugene Duff3, Vyacheslav Karolis3, Shaihan J Malik2, Mary A Rutherford1, David A Edwards1, and Joseph V Hajnal1,2

1Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 2Biomedical Engineering Department, King's College London, London, United Kingdom, 3FMRIB, Oxford University, Oxford, United Kingdom

The developing Human Connectome Project seeks to map connectivity in the human brain based on structural, functional and diffusion MRI data acquired from over 1000 subjects (neonatal and fetal).  A dedicated acquisition protocol has been developed to efficiently image fetal brain in utero. We describe here the methods and parameters being used alongside initial pre-processing steps. The acquisition protocol has been tuned to complement the neonatal data already collected while adapting to the difficult challenges of imaging the fetal brain in utero. It has been deployed to image over 145 fetuses to date with a success rate of ~90%.

245
Pitch: 16:00
Poster: 17:00
Plasma 24
Inversion Recovery Zero Echo Time (IR-ZTE) Imaging for Direct Myelin Detection in Human Brain
Hyungseok Jang1, Michael Carl2, Yajun Ma1, Yanjun Chen1, Saeed Jerban1, Eric Y Chang1,3, and Jiang Du1

1Department of Radiology, University of California San Diego, San Diego, CA, United States, 2GE Healthcare, San Diego, CA, United States, 3Radiology Service, VA San Diego Healthcare System, San Diego, CA, United States

In MRI, direct myelin imaging is challenging due to the short T2* decay (less than 0.5ms) and very low proton density. In the literature, it has been reported that ultrashort echo time (UTE) imaging can directly capture the fast decaying myelin signal. To further enhance the dynamic range, adiabatic inversion recovery (IR) preparation can be utilized so that the white matter signal can be suppressed. Moreover, dual echo UTE imaging scheme can suppress the remaining gray matter signal. In this study, we explore the feasibility of IR prepared zero echo time (IR-ZTE) imaging for direct myelin imaging in the human brain. 

246
Pitch: 16:00
Poster: 17:00
Plasma 25
Planar rosette spectroscopic imaging at 7T
Jullie W Pan1, Chan H Moon1, Victor Y Yushmanov1, Claud Schirda1, Frank Lieberman2, and Hoby P. Hetherington1

1University of Pittsburgh, Pittsburgh, PA, United States, 2UPMC, Pittsburgh, PA, United States

To make spectroscopic imaging clinically feasible, rapid and robust acquisitions with high SNR are necessary. We develop and apply rosette spectroscopic imaging at 7T using a 8x2 transceiver array and high degree B0 shimming to acquire rapid (<3min) whole plane brain studies at 0.7cc to 0.3cc resolution. To achieve high spectral bandwidth with moderate gradient demands, two temporal interleaves are used. We demonstrate the performance of this acquisition in controls and tumor patients, with use of regression statistics for determination of abnormality.

247
Pitch: 16:00
Poster: 17:00
Plasma 26
Whole brain sub-mm resolution T2* weighted anatomy imaging in less than 2 minutes
Arjan D. Hendriks1, Federico D’Agata1,2,3, Tim Schakel2, Liesbeth Geerts4, Dennis W.J. Klomp1, and Natalia Petridou1

1Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 2Department of Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands, 3Department of Neuroscience, University of Turin, Turin, Italy, 4Philips Healthcare, Best, Netherlands

T2* weighted imaging can be used to study both normal and pathological tissue. These images are commonly obtained using traditional gradient echo sequences which can lead to long scan times that are problematic particularly in a clinical setting. 3D EPI offers a faster alternative with scan times on the order of few minutes. Here, the scan time of T2* weighted 3D EPI scans is further reduced with a shot selective 2D CAIPI acquisition pattern. Whole brain T2* weighted anatomical scans with a resolution of 0.5 mm isotropic were acquired in 1:27 minutes. This holds promising perspectives for future applications in routine examinations.

248
Pitch: 16:00
Poster: 17:00
Plasma 27
Reduced Regional Cerebral Venous Oxygen Saturation is a Risk Factor for Cognitive Impairment in Hemodialysis Patients: A Susceptibility-weighted Image Mapping Study
Chao Chai1, Huiying Wang1, Jinping Li2, Jinxia Zhu3, Xianchang Zhang3, E. Mark Haacke4, Shuang Xia1, and Wen Shen1

1Department of Radiology, Tianjin First Central Hospital, Tianjin, China, 2Deparment of Hemodialysis, Tianjin First Central Hospital, Tianjin, China, 3MR Collaboration, Siemens Healthcare Ltd., Beijing, China, 4Department of Radiology, Wayne State University, Detroit, MI, United States

The purpose of this study was to noninvasively evaluate the changes of regional cerebral venous oxygen saturation (rSvO2) in hemodialysis patients using quantitative susceptibility-weighted image mapping (SWIM) and then to investigate the relationship between rSvO2, clinical risk factors, and neuropsychological testing results. The results suggest that cerebral rSvO2 is reduced in hemodialysis patients and that this reduction may correlate with neurocognitive dysfunction. Hematocrit, iron, glucose, and pre- and post-dialysis DBP were independent risk factors for reduced cerebral rSvO2

249
Pitch: 16:00
Poster: 17:00
Plasma 28
The UK7T Network’s Harmonized Neuroimaging Protocols
William T Clarke1, Olivier Mougin2, Ian D Driver3, Catarina Rua4, Andrew T Morgan5, Stuart Clare1, Susan Francis2, Richard Wise3, Adrian Carpenter4, Christopher T Rodgers4, Keith Muir5, and Richard Bowtell2

1Wellcome Centre for Integrative Neuroimaging, FMRIB, NDCN, University of Oxford, Oxford, United Kingdom, 2Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 3Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, United Kingdom, 4Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom, 5Imaging Centre of Excellence, University of Glasgow, Glasgow, United Kingdom

The UK7T Network is a consortium of 7-tesla-MRI capable sites in the United Kingdom, operating with three different scanner models, manufactured by two MR vendors. The Network has established a harmonized set of anatomical and functional MRI protocols for standardized neuroimaging across currently available human 7T scanners.

 

Here we make these harmonized protocols available to the community, along with example data, and describe the need for manual calibration to achieve harmonization across sites.


250
Pitch: 16:00
Poster: 17:00
Plasma 29
High-resolution MR imaging of human brain with multi-echo integrated SSFP
Huilou Liang1,2, Kaibao Sun1, Zhentao Zuo1,2,3, Jing An4, Yan Zhuo1,3, Danny J.J. Wang5, and Rong Xue1,2,6

1State Key Laboratory of Brain and Cognitive Science, Beijing MRI Center for Brain Research, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 2University of Chinese Academy of Sciences, Beijing, China, 3CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Beijing, China, 4Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, China, 5Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, CA, United States, 6Beijing Institute for Brain Disorders, Beijing, China

Balanced SSFP (bSSFP) has been used in structural and functional MRI, but always suffered from banding artifacts. While phase cycling was widely used to reduce banding artifact, it would take more scan time. Recently, integrated SSFP (iSSFP) was introduced to acquire banding-free images in shorter scan time than phased-cycled bSSFP. In this work, multi-echo iSSFP was further developed to improve SNR and acquire ultrahigh-resolution images with moderate scan time at 7T. Phantom and in vivo experiments demonstrated that the combined image produced by weighted averaging of multi-echo iSSFP showed obvious SNR and contrast improvement and inherited the characteristics of bSSFP.

251
Pitch: 16:00
Poster: 17:00
Plasma 30
Quantitative Susceptibility Mapping: In Vivo Biomarkers for Cerebral Cavernous Malformations Related Epilepsy
Li Ma1,2,3, Chunxue Wu4, Shuo Zhang1,2, Zongze Li3, Lizhi Xie5, Xiaolin Chen1,2,3, Xun Ye1,2, Hao Wang1,2, Yuanli Zhao1,2,3, Shuo Wang1,2, and Jizong Zhao1,2

1Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China, 2China National Clinical Research Center for Neurological Diseases, Beijing, China, 3Department of Neurosurgery, Peking University International Hospital, Beijing, China, 4Department of Neuroradiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China, 5GE Healthcare, China, Beijing, China

Hemosiderin deposits surrounding the cerebral cavernous malformations (CCMs) had been proposed to be associated with the pathogenesis of CCM-related epilepsy (CRE). An increased perilesional and extralesional iron deposition were found in CCMs with epilepsy through susceptibility maps of quantitative susceptibility mapping (QSM). To investigate novel biomarkers for the in vivo and longitudinal evaluation of CCM lesions with epilepsy, this study was to explore the iron quantity in CCMs patients with CRE using quantitative susceptibility mapping.


Power Pitch

Pitch: Molecular & Metabolic Imaging

Power Pitch Theater C - Exhibition Hall
Monday
Pitches: 16:00 - 17:00
Posters: 17:00 - 18:00
Moderators: Charles Cunningham & Justin Lau
(no CME credit)
252
Pitch: 16:00
Poster: 17:00
Plasma 31
Probing Cerebral Lactate Compartmentalization with Hyperpolarized Diffusion Weighted 13C MRI
Jeremy W Gordon1, Shuyu Tang1, Xucheng Zhu1, Daniel B Vigneron1, and Peder EZ Larson1

1UCSF, San Francisco, CA, United States

Hyperpolarized 13C MRI has been used to non-invasively measure metabolism in real-time. However, perfusion and transporter expression can impact the compartmentalization of metabolites. In this work, we investigated the feasibility of diffusion weighted imaging of lactate generated from HP [1-13C]pyruvate in the human brain to assess lactate efflux and compartmentalization in a healthy volunteer. Whole brain lactate ADC values were 0.37ⅹ10-3 mm2/s, 0.29ⅹ10-3 mm2/s, and 0.41ⅹ10-3 mm2/s when diffusion gradients were applied in the X, Y, and Z direction, respectively, demonstrating the feasibility of diffusion weighted HP 13C MRI in a clinical setting.

253
Pitch: 16:00
Poster: 17:00
Plasma 32
Imaging a hallmark of cancer: hyperpolarized [U-2H, U-13C]-glucose and hyperpolarized [1-13C]-dehydroascorbic acid can monitor TERT expression in gliomas
Pavithra Viswanath1, Georgios Batsios1, Russell O Pieper2, and Sabrina M Ronen1

1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 2Neurological Surgery, University of California San Francisco, San Francisco, CA, United States

Expression of telomerase reverse transcriptase (TERT) is a fundamental hallmark of cancer. Identification of imaging biomarkers of TERT expression will facilitate non-invasive assessment of tumor burden and response to therapy. Our studies in glioma indicate that TERT expression leads to increased redox capacity characterized by elevated 1H-MRS-detectable glutathione and NADPH. Concomitantly, TERT increases 13C-MRS-detectable flux of glucose through the pentose phosphate pathway, which provides NADPH. Importantly, hyperpolarized [U-2H, U-13C]-glucose and hyperpolarized [1-13C]-dehydroascorbic acid can image these alterations in glucose and redox metabolism. Our study identifies potential non-invasive translational metabolic imaging probes of TERT expression in glioma and possibly other cancers.

254
Pitch: 16:00
Poster: 17:00
Plasma 33
Initial experience of applying bolus tracking and real-time B0/B1 calibration for human hyperpolarized 13C imaging
Shuyu Tang1,2, Jeremy Gordon1, Robert Bok1, James Slater1, Jane Wang1, Daniel Vigneron1, and Peder Larson1

1University of California at San Francisco, San Francisco, CA, United States, 2University of California at Berkeley, berkeley, CA, United States

A new hyperpolarized 13C MRI approach with bolus tracking and real-time B0/B1 calibration was developed and tested in 4 human HP 13C MRI studies of brain, prostate, kidney and pancreas metabolism. The use of this framework demonstrated improved accuracy and robustness for human hyperpolarized 13C imaging.

255
Pitch: 16:00
Poster: 17:00
Plasma 34
Hyperpolarized C-13 bSSFP Imaging of the Human Brain
Eugene Milshteyn1,2, Cornelius von Morze3, Jeremy W. Gordon3, Galen D. Reed4, Adam Autry3, Hsin-Yu Chen3, Daniele Mammoli3, Robert A. Bok3, James B. Slater3, Mark Van Criekinge3, Lucas Carvajal3, Duan Xu3, Peder E. Z. Larson3, Sarah J. Nelson3, John Kurhanewicz3, and Daniel B. Vigneron3

1Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 4GE Healthcare, Dallas, TX, United States

Current early phase clinical trials of hyperpolarized C-13 imaging of the brain, prostate, and liver have demonstrated the exceptional ability to rapidly visualize metabolism of pyruvate at high spatiotemporal resolutions. Prior human studies have used MRSI, EPSI, EPI, and spiral MRI and MRSI. In this study, we investigated for the first time the bSSFP sequence with its high SNR efficiency for human hyperpolarized C-13 imaging of pyruvate and lactate. This research showed the ability to acquire dynamic 1-1.5cm isotropic bSSFP images of the human brain in a clinical setting.

256
Pitch: 16:00
Poster: 17:00
Plasma 35
Imaging the circumferential hyperpolarized 13C-bicarbonate distribution in the normal heart
Angus Z Lau1, Albert P Chen2, and Charles H Cunningham3,4

1University of Toronto, Toronto, ON, Canada, 2GE Healthcare, Toronto, ON, Canada, 3Medical Biophysics, University of Toronto, Toronto, ON, Canada, 4Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada

A typical observation in hyperpolarized 13C cardiac imaging is that the bicarbonate images are not circumferential, near the apex, even in healthy subjects, which precludes interrogation of metabolism in the posterior myocardium. A common explanation for the signal drop-off is anterior receive coil sensitivity. In this abstract, we demonstrate that this is not necessarily the case. A significant source of reduced signal results from B0 inhomogeneity in the posterior wall. Shortened readout durations which achieve higher kmax are shown to enable high resolution imaging of the circumferential bicarbonate distribution in pigs.

257
Pitch: 16:00
Poster: 17:00
Plasma 36
Hyperpolarized [1-13C]pyruvate MRS in a large animal model of partial renal obstruction supports clinical use in patients
Esben Søvsø Szocska Hansen1, Uffe Kjærgaard1, Rasmus Stilling Tougaard1,2, Rolf F. Schulte3, Hans Stødkilde-Jørgensen1, and Christoffer Laustsen1

1MR Research Centre, Aarhus University, Aarhus N, Denmark, 2Department of Cardiology, Aarhus University Hospital, Skejby, Denmark, 3GE Healthcare, Munich, Germany

Hyperpolarized [1-13C]pyruvate was used in this study to explorer the capability of detecting ischemic injury in the kidneys and to present the heterogeneity from the different kidney compartments. This was done using Michaelis–Menten kinetics by obtaining data in the an saturation recovery setup. Ischemic injuries was observed and in close correlation to standard perfusion MRI. The results from this study shows promise for the human introduction of this method.

258
Pitch: 16:00
Poster: 17:00
Plasma 37
Imaging metabolic heterogeneity in breast cancer using hyperpolarized 13C-MRSI
Ramona Woitek1, Mary A McLean2, James T Grist1, Raquel Manzano Garcia2, Turid Torheim2, Elena Provenzano2,3, Oscar M Rueda2, Andrew B Gill1, Andrew J Patterson4, Frank Riemer1, Joshua Kaggie1, Stephan Ursprung1, Fulvio Zaccagna1, Surrin S Deen1, Marie-Christine Laurent1, Matthew Locke1, Amy Frary1, Sarah Hilborne1, Chris Boursnell2, Titus Lanz5, Amy Schiller4, Ilse Patterson4, Bruno Carmo4, Rhys Slough4, Richard Baird6, Evis Sala1,7, Bristi Basu2,6, Jean Abraham6,8, Suet-Feung Chin2, Martin J Graves1, Fiona J Gilbert1, Carlos Caldas2,3,6, Kevin M Brindle2, and Ferdia A Gallagher1,7

1Department of Radiology, University of Cambridge, Cambridge, United Kingdom, 2CRUK Cambridge Institute, Cambridge, United Kingdom, 3Cambridge Breast Unit, Addenbrooke's Hospital, Cambridge University Hospital NHS Foundation Trust, NIHR Cambridge Biomedical Research Centre, Cambridge, United Kingdom, 4Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom, 5Rapid Biomedical GmbH, Rimpar, Germany, 6Department of Oncology, University of Cambridge, Cambridge, United Kingdom, 7Department of Radiology, Addenbrooke’s Hospital, Cambridge University Hospital NHS Foundation Trust and NIHR, Cambridge, United Kingdom, 8Cambridge Breast Unit, Addenbrooke’s Hospital, Cambridge University Hospital NHS Foundation Trust and NIHR, Cambridge, United Kingdom

13C magnetic resonance spectroscopic imaging (13C-MRSI) is a promising technique for elucidating metabolic heterogeneity in breast cancer. We used 13C-MRSI to evaluate the extent of glycolysis in different histologic and molecular breast cancer subtypes and correlated these findings with the expression of a key transmembrane transporter (MCT1) and glycolytic enzyme (LDHA). In addition to a strong correlation between glycolysis and tumor volume, there was higher expression of MCT1 and LDHA as well as CAIX, a hypoxia marker, in the more glycolytic tumors. This is the first study in humans to demonstrate the relationship between intertumoral heterogeneity on gene expression analysis and 13C-MRSI.

259
Pitch: 16:00
Poster: 17:00
Plasma 38
Kinetic Modeling of Hyperpolarized [1-13C]Lactate Metabolism in a Mouse Model of Ischemic Stroke
Thanh Phong Lê1,2, Lara Buscemi3, Elise Vinckenbosch1, Mario Lepore4, Rolf Gruetter 2,5,6, Lorenz Hirt 3, Jean-Noël Hyacinthe 1,7, and Mor Mishkovsky 2

1Geneva School of Health Sciences, University of Applied Sciences and Arts Western Switzerland (HES-SO), Geneva, Switzerland, 2Laboratory of Functional and Metabolic Imaging, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland, 3Department of Clinical Neurosciences, Centre hospitalier universitaire Vaudois (CHUV), Lausanne, Switzerland, 4Centre d'Imagerie Biomédicale (CIBM), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland, 5Department of Radiology, University of Geneva (UNIGE), Geneva, Switzerland, 6Department of Radiology, University of Lausanne (UNIL), Lausanne, Switzerland, 7Image Guided Intervention Laboratory, University of Geneva (UNIGE), Geneva, Switzerland

Stroke is the second cause of death and third leading cause of disability worldwide. Lactate injection was found to provide neuroprotection in preclinical models of ischemic stroke.

Alteration of the metabolism induced by ischemia can be measured in real time using magnetic resonance with hyperpolarized 13C labeled probes.

This study aims at investigating the feasibility of quantifying changes in the kinetics of hyperpolarized [1-13C]lactate metabolism following ischemia in a mouse model of stroke in order to assess the potential of hyperpolarized lactate as a theranostic agent for stroke.


260
Pitch: 16:00
Poster: 17:00
Plasma 39
Assessment of intracellular lactate relaxation, production and efflux rates in cells using hyperpolarized 13C MR
Fayyaz Ahamed1, Mark Van Criekinge2, Zhen J. Wang2, John Kurhanewicz2, Peder Larson2, and Renuka Sriram2

1University of California, Berkeley, Berkeley, CA, United States, 2Department of Radiology, University of California, San Francisco, San Francisco, CA, United States

Enzymatic conversions can now be measured with hyperpolarized 13C MR on a sub-minute time scale. Using this technology we have shown that renal cell carcinoma cells of varying aggressiveness in 3D culture in bioreactors (5mm NMR tube) can monitor both lactate production and its efflux in real time. Using this platform, we have robustly characterized certain parameters that are difficult to measure in vivo, such as intracellular longitudinal relaxation time and kinetic transport rate. Further validation of these measures were obtained by fitting the same model to data from cells treated with transporter inhibitor.

261
Pitch: 16:00
Poster: 17:00
Plasma 40
Fluorine-19 MR at 21.1 Tesla for Enhanced Detection of Brain Inflammation
Sonia Waiczies1, Jens Rosenberg2, Paula Ramos Delgado1, Ludger Starke1, Joao dos Santos Periquito 1, Christian Prinz1, Jason M. Millward1, Andre Kuehne3, Helmar Waiczies3, Andreas Pohlmann1, and Thoralf Niendorf1

1Max Delbrueck Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany, 2The National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, United States, 3MRI TOOLs GmbH, Berlin, Germany

Fluorine-19 (19F) MR methods are invaluable for several applications including detection of brain inflammation but suffer from inherently low signal-to noise ratio (SNR). A magnetic field increase from 9.4 to 21.1 Tesla was studied as strategy for increasing signal sensitivity. As a result of an SNR increase, inflammation regions undetected at 9.4T were revealed at 21.1T. Although the SNR gain at 21.1T does not reach that achieved with a cryogenic quadrature RF surface probe (19F-CRP) at 9.4T, increased sensitivity was observed throughout the whole field of view at 21.1T, from ventral to dorsal head regions.  

262
Pitch: 16:00
Poster: 17:00
Plasma 41
Fluorine MRI-Visible Mixed-Alginate Gradient Fluorocapsules for Image-Guided Diabetes Treatment
Dian R Arifin1, Genaro Paredes-Juarez1, Paul de Vos2, and Jeff W. M. Bulte1,3,4,5

1Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2Pathology and Medical Biology, University of Groningen, Groningen, Netherlands, 3Oncology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States, 4Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, United States, 5Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD, United States

A promising treatment of auto-immune juvenile diabetes is transplantation of beta islet cells. Islets can be encapsulated inside semi-permeable microcapsules to protect them against the patients’ immune system. Low islet survival and the lack of means to monitor the implants are major issues. We employed mixed-alginate gradient (MAG) microcapsules that better support human islet viability compared to currently used microcapsules. By labeling the capsules with clinically used agent CS-1000, we created MAG fluorocapsules which appeared as hot spots in mice on 19F MRI. MAG fluorocapsules offer a drug-free means to treat diabetic patients long-term while enabling imaging of transplanted islets.

263
Pitch: 16:00
Poster: 17:00
Plasma 42
Efficient Dictionary-based Attenuation Correction for combined PET-MR systems
Matteo Cencini1,2, Guido Buonincontri2, and Michela Tosetti2,3

1Department of Physics, University of Pisa, Pisa, Italy, 2IMAGO7 Foundation, Pisa, Italy, 3IRCCS Stella Maris, Pisa, Italy

In many diagnostic applications, a correct photon attenuation correction is crucial for quantifying the uptake of a PET tracer. While in PET/CT scanners attenuation map is readily estimated from CT Hounsfield units, in combined PET/MRI scanners it must be obtained by processing of high resolution images. This map must then be co-registered to low resolution PET map, wasting acquisition time. Here, we propose an efficient approach based on a fast transient-state acquisition and a three-component signal model: this allow to obtain tissue fraction maps, which can be used to estimate attenuation map, directly at PET resolution.

264
Pitch: 16:00
Poster: 17:00
Plasma 43
An MR based PET attenuation correction using a deep learning approach and evaluation in prostate cancer patients
Andrii Pozaruk1,2, Kamlesh Pawar1,3, Shenpeng Li1,4, Alexandra Carey1,5, Yen-Cheng Henry Pan6, Viswanath P Sudarshan1,7, Marian Cholewa2, Jeremy Grummet6, Zhaolin Chen1,4, and Gary Egan1,3

1Monash Biomedical Imaging, Monash University, Clayton, Australia, 2Department of Biophysics, Faculty of Mathematics and Natural Sciences, University of Rzeszow, Rzeszow, Poland, 3Monash Institute of Cognitive and Clinical Neurosciences and School of Psychological Sciences, Monash University, Clayton, Australia, 4Department of Electrical and Computer Systems Engineering, Monash University, Clayton, Australia, 5Monash Imaging, Monash Health, Clayton, Australia, 6Department of Surgery, Monash University, Melbourne, Australia, 7Department of Computer Science and Engineering, Indian Institute of Technology, Bombay, India

Accurate Magnetic Resonance (MR) imaging based attenuation correction is crucial for quantitative Positron Emission Tomography (PET) in simultaneous MR/PET imaging. However, due to a lack of robust MR bone imaging methods, MR based attenuation correction remains a critical issue in MR/PET image reconstruction. In this work, we developed and evaluated a deep learning (DL) based MR based attenuation correction method for improved MR/PET quantification accuracy in prostatic cancer imaging.

265
Pitch: 16:00
Poster: 17:00
Plasma 44
Impact of attenuation correction on image-derived input function and cerebral blood flow quantification with simultaneous [15O]-water PET/MRI
Trine Hjoernevik1, Mohammad Mehdi Khalighi2, Sandeep Kaushik3, Yosuke Ishii2,4, Greg Zaharchuk2, and Audrey Peiwen Fan2

1Oslo University Hospital, Oslo, Norway, 2Radiology, Stanford Unversity, Stanford, CA, United States, 3GE Global Research, Bangalore, India, 4Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan

This study evaluated the impact of attenuation correction (AC) on image-derived input functions (IDIF) and kinetic modeling of cerebral blood flow (CBF) parameters for simultaneous [15O]-water PET/MRI in the brain. Atlas-based AC led to 4.3% underestimation of the IDIF peak and 8-18% overestimation of absolute CBF in different brain perfusion states. On the other hand, zero echo time (ZTE)-based AC provided reproducible quantification of absolute CBF, comparable to the deep learning AC reference that was trained on real CT images. Attenuation correction is an important consideration for IDIF calculation and parametric mapping with PET/MRI; and ZTE-based and deep learning-based AC provide suitable quantitative accuracy for [15O]-water studies.

266
Pitch: 16:00
Poster: 17:00
Plasma 45
Spatial profiling of endogenous cellular iron MRI contrast by machine vision classifies macrophage infiltration in breast cancer models of metabolic- and immune-therapy
Avigdor Leftin1,2 and Jason Koutcher1

1Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Radiology, Stony Brook Medicine, Stony Brook, NY, United States

Tumor macrophage response to therapy is conventionally detected with iron nanoparticle-enhanced MRI.  However, endogenous cellular iron detection methods exist that can bypass caveats intrinsic to contrast agent use. We demonstrate that contrast-agent free multi-gradient echo R2* relaxometry iron MRI and machine vision analysis approaches can map tumor macrophage iron deposits and detect cellular response to metabolic and immunotherapy in preclinical models of breast cancer. Feasibility of endogenous macrophage imaging is shown, and the value of the cellular MRI biomarker is demonstrated as a function of treatment and tumor model. 


Oral

Novel MR & MR-Compatible Technology

Room 512A-H
Monday 16:00 - 18:00
Moderators: Clarissa Cooley & Suryanarayana Umesh Rudrapatna
267
16:00
Auxiliary PTx system for active control of induced RF currents in conductive guidewires
Felipe Godinez1, Joseph V Hajnal1, and Shaihan J Malik1

1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom

The risk of RF-induced currents makes use of electrically conductive guidewires for cardiac catheterization procedures potentially unsafe for MRI. By using a parallel transmit coil array (PTx) system it is possible to generate RF field modes that can be utilized for safe imaging, and also guidewire visualization. As the induced RF currents can change with the guidewire position and operator handling, the control modes become a moving target. In this work we present an actively controlled PTx system that enables safe operation during a procedure in which electrical conditions are changing, and demonstrate this experimentally.

268
16:12
RF transparent ultrafast gradient insert
Dennis Klomp1,2, Edwin Versteeg1, Riccardo Metere3, Andrew Webb4, Erik Van den Boogert3, David G Norris3, Matrino Borgo5, and Jeroen Siero1,6

1Radiology, UMC Utrecht, Utrecht, Netherlands, 2MRCoils, Zaltbommel, Netherlands, 3Donders institute for Brain Cognition and Behaviour, Radboud University, Nijmegen, Netherlands, 4Gorter center, Leiden UMC, Leiden, Netherlands, 5Futura Composites, Heerhugowaard, Netherlands, 6Spinoza Center for Neuroimaging, Amsterdam, Netherlands

Ultrafast gradient insert coils can boost EPI performance when designed as an independent 4th gradient chain. However, at high operating frequencies, substantial eddy currents will be generated in the shields of RF coils. Here we show that RF shields can be removed without compromising MRI performance yet enabling two orders of magnitude increased gradient efficiency at high frequency.

269
16:24
Portable, single-sided magnetic resonance sensor for hydration status assessment via multicomponent T2 relaxometry
Ashvin Bashyam1,2, Chris J Frangieh1,2, and Michael J Cima2,3

1Electrical Engineering & Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, 2David H. Koch Institute For Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States, 3Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States

Undiagnosed dehydration compromises health outcomes across many populations including the elderly, infants, soldiers and athletes. Here we introduce a miniature (~1000 cm3), portable (~4 kg), single-sided magnetic resonance (MR) sensor capable of identifying and quantifying fluid loss induced by dehydration. Multicomponent T2 relaxometry of skeletal muscle tissue enables the measurement of distinct fluid compartments. We first quantify fluid loss induced by dehydration with multicomponent T2 relaxometry using a standard MRI. We then extend these findings and demonstrate a portable, low-field MR sensor exhibits comparable performance via a similar measurement while offering significantly reduced sensor mass, measurement time, and system complexity.

270
16:36
MRI Powered and Triggered Current Stimulator for Concurrent Stimulation and MRI
Ranajay Mandal1, Nishant Babaria2, Jiayue Cao1, Kun-Han Lu3, and Zhongming Liu1,2,3

1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States, 2MR-LINK LLC, West Lafayette, IN, United States, 3Electrical and Computer Engineering, Purdue University, West Lafayette, IN, United States

The integration of stimulation, recording and high-field MRI has significant potential to evaluate different organs (brain, heart, gut etc.). However, externally powered devices consisting of cables and connectors for powering and synchronization may perturb the magnetic field within the MRI system and create additional safety concerns at high-fields. Here we present an MRI powered and triggered system, namely X-ON, to deliver electrical stimulation during MRI operation. The MR-compatible system can harvest wireless energy from varying gradient fields and provide programmable current stimulation in synchronization with MRI or fMRI acquisition.

271
16:48
High Resolution TRASE by Rapid Echo Encoding with Twisted Solenoid RF Phase Gradient Coils
Hongwei Sun1, Aaron Purchase1, Abbas AlZubaidi2, Pallavi Bohidar2, Gordon Sarty2, Boguslaw Tomanek1, and Jonathan C. Sharp1

1Department of Onoclogy, University of Alberta, Edmonton, AB, Canada, 2Department of Biomedical Engineering, University of Saskatchewan, Saskatoon, SK, Canada

TRASE is an MRI k-space encoding method that uses radio-frequency transmit phase gradient fields to achieve millimeter-level spatial resolution. To avoid resolution loss, the total echo train duration should be less than 1.2 times T2. However, previously demonstrated TRASE experiments have been limited by a large echo spacing (~1100 us). Here we present the use of the twisted solenoid to achieve short echo spacing of ~370 us, while remaining within SAR limits. This rapid echo encoding will enable in vivo imaging of short T2 tissues (e.g. ~50ms T2 for muscle at 0.2T) with resolution of 1.2 mm per pixel.

272
17:00
The design of a homogenous large-bore Halbach array for low field MRI
Thomas O'Reilly1, Wouter Teeuwisse1, Lukas Winter2, and Andrew Webb1

1C.J. Gorter Center for High Field MRI, Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany

The homogeneity of cylindrical Halbach arrays for low-field MRI is compromised by the finite length and discretisation into individual magnets. In this work we design and construct a large-bore Halbach array intended for imaging hydrocephalus in young children. The magnet is constructed using 23 double-layer Halbach rings with layer radii optimised for homogeneity. Simulated magnetic field strength and homogeneity over a 20cm spherical volume are 50.64mT and 433ppm, respectively. The homogeneity of the realised Halbach array is slightly degraded compared to simulations, but is sufficiently high to allow the use  of conventional spatial encoding methods on such a system.

273
17:12
Wireless coil as a portable and practical alternative to a dedicated transceive coil for extremities MRI at 1.5T
Alena Shchelokova1, Georgiy Solomakha1, Ekaterina Brui1, Anna Mikhailovskaya1, Irina Melchakova1, and Anna Andreychenko1

1Department of Nanophotonics and Metamaterials, ITMO University, Saint Petersburg, Russian Federation

We show for the first time that a metamaterial inspired, volumetric wireless coil demonstrates similar performance as the same size, cable-connected volume transceiver coil for extremities MRI at 1.5T.  Numerical analysis and in vivo human wrist imaging with the wireless coil showed proper quality images with no artefacts and the same transceive efficiencies, while the global radiofrequency safety was 190% higher, compared to the commercial extremity coil.

274
17:24
MRI with Sub-Millisecond Temporal Resolution: An Example Employing Spatially Resolved Eddy Current Characterization
Zheng Zhong1,2, Muge Karaman1,2, and Xiaohong Joe Zhou1,2,3

1Center for MR Research, University of Illinois at Chicago, Chicago, IL, United States, 2Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, 3Department of Radiology and Neurosurgery, University of Illinois at Chicago, Chicago, IL, United States

Increasing the temporal resolution has been a major motivation for MRI technical development. Despite considerable progress, the presently achievable temporal resolution of MRI is limited to tens of milliseconds. We report a novel MRI technique, which we call Sub-Millisecond Imaging of cycLic Event (SMILE), that is capable of capturing periodic processes with sub-millisecond resolution. This technique is demonstrated by employing an example of characterization of eddy currents with short time constants.

275
17:36
Equivalent-Charge-Based Optimization of Spokes-and-Hub Magnets for Hand-Held and Classroom MR Imaging
Irene Kuang1, Nicolas Arango1, Jason Stockmann2,3, Elfar Adalsteinsson1,4, and Jacob White1

1Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, 2Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, United States

Differentiating the potential from end-cap equivalent charges is so efficient at computing fields from bar magnets, that in less than minute, a laptop running MATLAB can computationally-optimize field uniformity in hundred-bar wagon-wheel (or spokes-and-hub) magnets.  And optimized spokes-and-hub magnets have several advantages for hand-held and classroom low-field single-slice MR imaging (50-200 mT). Their frame is open, and they are easily assembled and scaled. We demonstrate several such magnets, from finger to wrist to infant size, and match magnetic field measurements to quadrature-based equivalent-charge simulation.  We also demonstrate generating spin echoes using a spokes-and-hub magnet in a 200 mT tabletop imager.

276
17:48
A Fast and Easy-to-Use Tool for designing High-Permittivity Pads for 3T Body and 7T Neuroimaging Applications
Jeroen van Gemert1, Wyger Brink2, Andrew Webb2, and Rob Remis1

1Circuits and Systems Group, Delft University of Technology, Delft, Netherlands, 2C.J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, Netherlands

High-permittivity pads have proved effective for addressing B1+ inhomogeneities for neuroimaging at 7T and body imaging at 3T. In contrast with the ease of constructing these pads, obtaining an appropriate design involves sophisticated and time-consuming electromagnetic field simulations, meaning that in many applications this technique is not fully exploited. We have therefore developed an easy-to-use software tool which can be run on a standard desktop PC to design dielectric pads for 3T body and 7T neuroimaging applications.


Oral

Breast

Room 513D-F
Monday 16:00 - 18:00
Moderators: Rebecca Rakow-Penner & Savannah Partridge
277
16:00
Quantification of Benign and Malignant Breast Tumor Cellularity
Zezhong Ye1, Na Zhao2, Joshua Lin1, Sam E. Gary3, Jeffrey D. Viox4, Chunyu Song1, Ruimeng Yang5, Peng Sun1, Jie Zhan6, Qingsong Yang2, Jianping Lu2, and Sheng-Kwei Song1

1Radiology, Washington University School of Medicine, Saint Louis, MO, United States, 2Radiology, Changhai Hospital, Shanghai, China, 3Medical Scientist Training Program, The University of Alabama at Birmingham, Birmingham, AL, United States, 4Medicine, University of Missouri – Kansas City, Kansas City, MO, United States, 5Radiology, Guangzhou First People’s Hospital, Guangzhou, China, 6Radiology, The First Affiliated Hospital of Nanchang University, Nanchang, China

Recent consensus suggested that breast MRI lacks the needed sensitivity or specificity to detect breast cancer. Breast cancer over-diagnosis may result in over-treatments. We recently modified diffusion basis spectrum imaging (DBSI) to accurately localize breast cancer lesion and quantify cancer cellularity. Results revealed that modified-DBSI afforded greater diagnostic sensitivity and specificity than ADC in distinguishing between tumor and benign tissues.

278
16:12
Combination of MRI quantitative measures improves prediction of residual disease following neoadjuvant chemotherapy (NAC) for breast cancer in the I-SPY 2 TRIAL
Wen Li1, David C. Newitt1, Lisa J. Wilmes1, Ella F. Jones1, Jessica Gibbs1, Elizabeth Li1, Bo La Yun1, John Kornak2, Bonnie N. Joe1, Christina Yau3, On behalf of the I-SPY 2 Consortium4, Laura J. Esserman3, and Nola M. Hylton1

1Radiology & Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 2Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, United States, 3Surgery, University of California San Francisco, San Francisco, CA, United States, 4Quantum Leap Healthcare Collaborative, San Francisco, CA, United States

This abstract presents the work of combining different MR measures to predict primary tumor residual after patients with breast cancer went through neoadjuvant chemotherapy. Three types of MR measures are investigated in this study: longest diameter, functional tumor volume, and apparent diffusion coefficient. Results showed that when all three types of MR measures are combined in the logistic regression model, it yielded the highest AUC compared to the model with only one of the MR measures. Results also suggested that measures taken at various treatment time points, not just pre-surgery, should be included in the prediction of the residual disease.

279
16:24
Improved lesion conspicuity and confidence level through suppressed background parenchymal enhancement in ultrafast breast dynamic contrast enhanced MRI
Maya Honda1, Masako Kataoka1, Mami Iima1, Akane Ohashi1, Ayami Ohno Kishimoto1, Rie Ota1, Marcel Dominik Nickel2, Masakazu Toi3, and Kaori Togashi1

1Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan, 2Siemens Healthcare GmbH. , Erlangen, Germany, 3Breast surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan

Ultrafast dynamic contrast enhanced (UF-DCE) MRI is known for its reduced background parenchymal enhancement (BPE), but the evidence is limited. We evaluated BPE, lesion conspicuity and confidence level of UF-DCE MRI compared with those of conventional DCE (C-DCE) MRI. BPE was reduced, and lesion conspicuity and confidence level were improved on UF-DCE MRI compared to C-DCE MRI, indicating another advantage of UF-DCE MRI when applied to younger women and for high-risk screening.

280
16:36
Co-registration of Breast Diffusion MR Images Across Multiple Time Points in a Longitudinal Study to Evaluate the Response to Neoadjuvant Chemotherapy
Guangyu Dan1,2, Muge Karaman1,3, Shunan Che4, Zheng Zhong1,3, Han Ouyang4, and Xiaohong Joe Zhou1,3,5

1Center for MR Research, University of Illinois at Chicago, Chicago, IL, United States, 2Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL, United States, 3Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, 4Department of Diagnostic Radiology, National Cancer Center and National Clinical Research Center for Cancer, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, 5Departments of Radiology and Neurosurgery, University of Illinois at Chicago, Chicago, IL, United States

Breast cancer is one of the most common cancers among women. Recently, several diffusion models have been proposed to characterize breast cancer. To extend these models for the assessment or prediction of treatment response of breast cancer, image co-registration throughout the time course of treatment is a significant challenge, particularly considering the vulnerability to deformation of the breast tissue. In this study, we demonstrate a 3D non-rigid co-registration method, and apply it to diffusion weighted (DW) images acquired in a longitudinal study during neoadjuvant chemotherapy.

281
16:48
Time-Varying Diffusion Patterns in Breast Cancer Linked to Prognostic Factors
Mami Iima1, Masako Kataoka1, Maya Honda1, Ayami Kishimoto Ohno1, Rie Ota1, Akane Ohashi1, Yuta Urushibata2, Thorsten Feiweier3, Masakazu Toi4, and Kaori Togashi1

1Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan, 2Siemens Healthcare K.K., Tokyo, Japan, 3Siemens Healthcare GmbH, Erlangen, Germany, 4Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan

We investigated the utility of diffusion time-dependence of ADC measurements for the differentiation of prognostic biomarkers in human breast tumors using OGSE and PGSE sequences. Malignant tumors had significantly lower ADC values with longer diffusion times. ADC change significantly correlated with Ki-67 expression. Significant association was found between ADC value (at the effective diffusion time of 5.1ms) and PgR expression. These associations indicate the potential of the diffusion-time-dependent ADC values as a tool to differentiate these prognostic biomarkers and highlight tumor heterogeneity without the need of contrast agents.

282
17:00
Breast lesion classification accuracy using intravoxel incoherent motion diffusion modelling is improved by incorporating all parameters and informative Bayesian priors
Neil Peter Jerome1,2, Igor Vidić3, Tone Frost Bathen1, Pål Erik Goa3, and Peter Thomas While4

1Institute for Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway, 2Department of Radiology and Nuclear Medicine, St Olavs Hospital, Trondheim, Norway, 3Department of Physics, Norwegian University of Science and Technology (NTNU), Trondheim, Norway, 4Department of Radiology and Nuclear Medicine, St Olavs University Hospital, Trondheim, Norway

Strategies for intravoxel incoherent motion (IVIM) diffusion imaging acquisition and analysis are often framed in terms of curve-matching, whereas for breast lesions, classification accuracy against histopathologic assessment is a true metric of functional imaging performance. In this study, we show that IVIM diffusion modelling is best able to discriminate breast lesions (23 benign, 29 malignant) when using all parameters, and when derived from Bayesian methods employing either Gaussian shrinkage or local homogeneity priors, with ROC AUC values increasing from 0.83 (D, conventional least-squares) to 0.92 (D+f+D*, shrinkage prior).

283
17:12
Pre-surgical evaluation of residual cancer by breast MRI after neoadjuvant systemic treatment: DWI-based algorism
Rie Ota1, Masako Kataoka1, Maya Honda1, Shotaro Kanao2, Mami Iima1, Kanae Miyake Kawai1, Akane Ohashi1, Ayami Ohno Kishimoto1, Takaki Sakurai3, Tatsuki R Kataoka3, Masakazu Toi4, and Kaori Togashi1

1Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University graduate school of medicine, Kyoto, Japan, 2Kobe City Medical Center General Hospital, Kobe, Japan, 3Department of Pathology, Kyoto University Hospital, Kyoto, Japan, 4Department of Breast Surgery, Kyoto University Hospital, Kyoto, Japan

We aimed to re-evaluate DWI of pre-surgical MRI as a clue to diagnose pCR or non-pCR. DCE-MRI including kinetic information were also evaluated for comparison.  DWI-based evaluation of residual disease in pre-surgical MRI demonstrate excellent diagnostic performance. On the other hand, residual disease is difficult to evaluate based on kinetic information. DWI-based evaluation of residual disease is a useful approach in pre-surgical evaluation of breast cancer following neoadjuvant systemic treatment.

284
17:24
Independent Validation of U-Net Based Breast and Fibroglandular Tissue Segmentation Method on MRI Datasets Acquired Using Different Scanners
Yang Zhang1, Jeon-Hor Chen1,2, Kai-Ting Chang1, Vivian Youngjean Park3, Min Jung Kim3, Siwa Chan4, Peter Chang1, Daniel Chow1, Alex Luk1, Tiffany Kwong1, and Min-Ying Lydia Su1

1Department of Radiological Sciences, University of California, Irvine, CA, United States, 2Department of Radiology, E-Da Hospital and I-Shou University, Kaohsiung, Taiwan, 3Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea, Democratic People's Republic of, 4Department of Medical Imaging, Taichung Tzu-Chi Hospital, Taichung, Taiwan

Segmentation of breast and fibroglandular tissue (FGT) using the U-net architecture was implemented using training MRI from 286 patients, and the developed model was tested in independent validation datasets from 28 healthy women acquired using 4 different MR scanners. The dice similarity coefficient was 0.86 for breast, 0.83 for FGT; and the accuracy was 0.94 for breast and 0.93 for FGT. The results on MRI acquired using different MR scanners were similar. U-net provides a fully automatic, efficient, segmentation method in large MRI datasets for evaluating its role on breast cancer risk assessment and hormonal therapy response prediction.

285
17:36
Can Machine-Learning-based Radiomics of Whole Tumor on MR Multiparametric Maps Predict the Ki-67 index of Breast Cancer?
Tianwen Xie1, Qiufeng Zhao2, Caixia Fu3, Robert Grimm4, Yajia Gu1, and Weijun Peng1

1Radiology, Fudan University Shanghai Cancer Center, Shanghai, China, 2Radiology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China, 3MR Application Development, Siemens Shenzhen Magnetic Resonance, Shenzhen, China, Shenzhen, China, 4MR Application Predevelopment, Siemens Healthcare, Erlangen, Germany

There has recently been increased interest in quantitative MR parameters for assessing tumor proliferation. A total of 134 consecutive patients with pathologically-proven invasive ductal carcinoma were retrospectively evaluated. We extracted the whole-tumor histogram and textural features from an ADC map and DCE-MRI semi-quantitative maps. The LASSO for feature selection and the KNN algorithm for classification were performed. Classifications performed between Ki-67-positive and Ki-67-negative groups resulted in an accuracy of 75.4% using three texture features, whereas classification with only the entropy of ADC yielded an accuracy of 74.6%.

286
17:48
Convolutional neural network uses pre-chemotherapy breast MRI data to predict which tumors will exhibit a pathologic complete response post-chemotherapy
Sarah Eskreis-Winkler1,2, Harini Veeraraghavan2, Natsuko Onishi2, Shreena Shah1, Meredith Sadinski2, Danny Martinez2, Yi Wang1, Elizabeth Morris2, and Elizabeth Sutton2

1Weill Cornell Medicine, New York, NY, United States, 2Memorial Sloan Kettering Cancer Center, New York, NY, United States

In this study, we evaluate the performance of a convolutional neural network (CNN) to predict pathologic complete response based on pre-treatment breast MRI images. We achieved moderate accuracy in this initial feasibility study. Future work with larger patient datasets will improve CNN performance.


Oral

Neurovascular

Room 510A-D
Monday 16:00 - 18:00
Moderators: Moran Artzi
287
16:00
Arterial Spin Labeling Underestimates CBF in Regions with Fast Arrival Times: a Simultaneous [15O] PET/MRI Study with Acetazolamide Challenge
Yosuke Ishii1,2, Thoralf Thamn1,3, Jia Guo1,4, Mohammad Mehdi Khalighi5, Mirwais Wardak1, Dawn Holley1, Harsh Gandhi1, Jun Hyung Park1, Bin Shen1, Gary K Steinberg6, Frederick T Chin1, Greg Zaharchuk1, and Audrey Peiwen Fan1

1Radiology, Stanford University, Stanford, CA, United States, 2Neurosurgery, Tokyo Medial and Dental University, Tokyo, Japan, 3Center for Stroke Research Berlin (CSB), Charité - Universitätsmedizin Berlin, Berlin, Germany, 4Bioengineering, University of California Riverside, Riverside, CA, United States, 5Global Applied Science Lab, GE Healthcare, Menlo Park, CA, United States, 6Neurosurgery, Stanford University, Stanford, CA, United States

In this study, we investigated the effects of arterial transit time (ATT) reduction and the quantitative accuracy of standard and multi-delay arterial spin labeling (ASL) MRI on healthy controls and Moyamoya patients using acetazolamide (ACZ) by the voxel-wise parametric testing.

Administration of ACZ shortened ATT and extended the region where cerebral blood flow (CBF) was underestimated by standard ASL and by multi-delay ASL compared to simultaneous [15O]-water PET reference. Consideration of short ATT is critical for accurate ASL measurements of CBF in the deep gray matter and for quantification of cerebrovascular reactivity after a vasodilation challenge that decreases ATT.


288
16:12
ASL signal model for simultaneously measuring CBF and CBV based on ASL imaging for characterizing hemodynamic perfusion state in normal subjects and patients with moyamoya disease.
Hirohiko Kimura1, Yoshifumi Higashino2, Shota Ishida3,4, Naoyuki Takei5, Yasuhiro Fujiwara6, Masayuki Kanamoto3, Nobuyuki Kosaka7, and Hiroyuki Kabasawa8

1Radiology, University of Fukui, Fukui, Japan, 2Neurosurgery, University of Fukui, Fukui, Japan, 3Radiological center, University of Fukui Hospital, Fukui, Japan, 4Division of Health Sciences, Graduate school of Medical Sciences, Kanazawa University, Kanazawa, Japan, 5MR application and Workflow, GE Healthcare JAPAN, HIno, Japan, 6Department of Medical Imaging, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan, 7Department of Radiology, University of Fukui, Fukui, Japan, 8GE Healthcare JAPAN, Hino, Japan

Not only cerebral blood flow (CBF) but also cerebral blood volume (CBV) plays an important role for the maintenance of cerebral blood perfusion. We hypothesized that the ASL signal difference caused by vessel suppression (VS) scheme should be dependent on arterial CBV fraction of total ASL signal. In this study, we introduced modified two-compartments model based on ASL signal with and without VS, so that we can calculate arterial volume fraction of total ASL signal. The objective of this study is to demonstrate the feasibility of arterial CBV map as well as CBF based on ASL imaging.

289
16:24
The Quantification of Feuromxytol Uptake on the Post Enhance in Intracranial Atherosclerotic Plaque by using a 3D high resolution Black Blood(BB) Multiple Echo(ME) T2* Imaging Technique
Seong-Eun Kim1, J Scott McNally1, Matthew Alexander1, Dennis L Parker1, Bradley D Bolster Jr2, Gerald S Treiman3,4, and Adam de Havenon5

1UCAIR, Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, United States, 2Siemens Healthcare, Salt Lake City, UT, United States, 3Department of Surgery, University of Utah, Salt Lake City, UT, United States, 4Department of Veterans Affairs, VASLCHCS, Salt Lake City, UT, United States, 5Department of Neurology, University of Utah, Salt Lake City, UT, United States

Post-gadoliniun enhancement(PGE) in ICAD may be related to endothelial dysfunction or breakdown or secondary to plaque inflammation. Delayed ferumoxytol imaging allows intravascular clearance with retention in the macrophages present in vulnerable atherosclerotic plaque. A 3D BB ME T2* Imaging technique allows the quantitative ferumoxytol imaging on delayed scans by measuring T2* in intracranial atherosclerotic plaque. We performed 3D BB T2* sequences on ten patients with ICAD and measured T2* changes between baseline and 72 hour after ferumoxytol injection. The iron nanoparticle uptake in symptomatic ICAD presented in this work may provide important mechanistic implications for the pathophysiology of PGE.

290
16:36
High Risk Characteristics of Cervicocranial Artery Dissection Associated with Ischemic Stroke: A Head and Neck Combined Vessel Wall MR Study
ye wu1, fang wu1, and qi yang1

1Xuanwu Hospital Capital Medical University, Beijing, China

The aim of this study was to investigate high risk characteristics of dissected artery using VWMRI. A total of 114 Patients with CeAD were prospectively recruited and 139 dissected vessels were analyzed. Dissected arteries in the stroke group showed a significantly higher prevalence of irregular surface, intraluminal thrombus and severe stenosis (>70%) compared with that of the non-stroke group. Logistic regression analysis showed that the presence of irregular surface and intraluminal thrombus were independently associated with ischemic stroke in CeAD. Our results provide insights into the vascular pathophysiology of symptomatic CeAD and may reveal important predictor of stroke in CeAD.

291
16:48
Cerebral hypometabolism measured with intravascular T2-prepared tissue relaxation with inversion recovery (T2-TRIR) and pCASL in adults with sickle cell disease
Lena Vaclavu1,2, Esben Thade Petersen3, Henri JMM Mutsaerts1, Jan Petr4, Charles BLM Majoie1, John C Wood5, Ed T VanBavel6, Bart J Biemond7, and Aart J Nederveen1

1Department of Radiology & Nuclear Medicine, Amsterdam UMC, Amsterdam, Netherlands, 2C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands, 3Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark, 4Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany, 5Department of Cardiology and Radiology, Children’s Hospital of Los Angeles, Los Angeles, CA, United States, 6Department of Biomedical Engineering & Physics, Amsterdam UMC, Amsterdam, Netherlands, 7Department of Hematology, Amsterdam UMC, Amsterdam, Netherlands

Cerebral metabolic rate of oxygen (CMRO2) quantifies the amount of oxygen consumed by the brain, and relies on continuous delivery of nutrients and oxygen via cerebral blood flow (CBF). In sickle cell disease (SCD), CBF is elevated to compensate for chronic anaemia. This study investigates CMRO2 in adults with SCD using T2-prepared tissue relaxation with inversion recovery (T2-TRIR). CBF increased after acetazolamide-induced vasodilation in both groups but CMRO2 reduced even further in SCD patients while it remained stable in controls. Our results suggest that cerebral shunting is exacerbated by high flow conditions.

292
17:00
Mean Transit Time and Capillary Transit Time Heterogeneity at the Basal Ganglia of Patients with Huntington’s Disease
Yi-Fen Yen1,2, Kenneth Kwong1,2, Suk-Tak Chan1,2, Steven M. Stufflebeam1,2, and H. Diana Rosas1,3

1Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States, 3Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States

We identified abnormally long mean transit time (MTT) and large capillary transit time heterogeneity (CTH) in the basal ganglia of ten individuals with Huntington’s disease (HD) as compared to ten healthy control subjects. Since iron is elevated in the putamen and globus pallidus in HD [1], which can lead to an underestimation of relative cerebral blood flow (CBF) and cerebral blood volume (CBV), excessively prolonged MTT and CTH, which are ratios of CBV and CBF, could be utilized as relatively intact parameters for the estimation of perfusion deficits or breakdown in blood-brain barrier.  

293
17:12
White matter microstructural alterations in chronic, episodic, and aura migraine
Benjamin Ades-Aron1, Sait Ashina2, Bettina Conti1, Yvonne W Lui1, Mia Minen3, Dmitry S Novikov1, Timothy Shepherd1, and Els Fieremans1

1Radiology, Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States, 2Neurology, Beth Israel Deaconess Medical Center, Brookline, MA, United States, 3Neurology, New York University School of Medicine, New York, NY, United States

Migraine is associated with increased risk for stroke and white matter abnormalities, though the exact nervous tissue pathology remains poorly understood. This study used diffusion kurtosis imaging, a clinically feasible extension of diffusion tensor imaging, to compare white matter microstructural changes in migraineurs to healthy controls, and between their different subtypes: chronic, episodic, with and without aura. Using a voxel-wise statistical approach, we found that axial and radial kurtosis were significantly altered depending on migraine subtype. While radial kurtosis is significantly reduced in all migraine patients compared to controls, axial kurtosis is increased in episodic migraines with and without aura, suggesting different underlying pathology.

294
17:24
Evolution of cerebral hemodynamics and metabolism across the early lifespan in patients with sickle cell disease
Spencer L. Waddle1, Lori C. Jordan2, Meher R. Juttukonda1, Chelsea A. Lee2, Niral J. Patel2, and Manus J. Donahue1

1Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, 2Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, United States

Sickle cell disease (SCD) is an inherited hemolytic anemia with altered hemodynamics and increased stroke risk. However, lifetime trends in SCD cerebral hemodynamics and metabolism are poorly understood. We used non-invasive functional measures of cerebral blood flow (CBF) from arterial spin labeling, and oxygen extraction fraction (OEF) from T2-Relaxation-Under-Spin-Tagging MRI, to quantify hemo-metabolic patterns in controls (n=64) and SCD patients (n=125) across the early lifespan (6-40 years). CBF decreases with age in healthy controls (-3.2 mL/100g/min per decade) but increases in patients (5.2 mL/100g/min per decade). OEF was elevated in SCD, showing a similar slope with age as controls.

295
17:36
Differences in temporal cerebrovascular reactivity responses between patients with atherosclerotic and non-atherosclerotic intracranial disease: implications for optimal hypercapnic reactivity experiments
Meher Juttukonda1, Larry Davis1, Spencer Waddle1, Sarah Lants1, Matthew Fusco2, and Manus Donahue1

1Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, 2Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN, United States

Intracranial stenosis may be due to atherosclerotic or idiopathic non-atherosclerotic mechanisms, and each condition may incur different consequences on cerebral hemodynamics. The purpose of this study was to use a time regression analysis approach applied to hypercapnic BOLD fMRI data to evaluate how cerebrovascular reactivity (CVR) timing and maximum CVR may differ between patient groups and with vasculopathy extent. Time-to-maximum CVR may be lengthened in territories supplied by stenotic vessels in both patient groups; however, maximum CVR may be reduced on average only in patients with non-atherosclerotic disease, potentially indicating that arteriolar smooth muscle and/or endothelial function may differ substantially between conditions.

296
17:48
In-vivo validation of T2- and susceptibility-based SvO2 measurements with jugular vein catheterization under hypoxia and hypercapnia
Xin Miao1, Krishna Nayak1,2, and John Wood1,3

1Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States, 2Ming Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA, United States, 3Division of Cardiology, Children’s Hospital Los Angeles, Los angeles, CA, United States

This study aimed to validate T2- and susceptibility-based cerebral venous oxygen saturation (SvO2) measurements with the clinical standard, jugular vein catheterization. T2-relaxation-under-tagging (TRUST) and susceptibility-based oximetry (SBO) were performed on two healthy subjects with jugular catheterization and eleven subjects without catheterization under baseline, hypoxia and hypercapnia. TRUST tightly agreed with the jugular reference under hypercapnia but significantly underestimated SvO2 under baseline and hypoxia. Bias between SBO and the reference was independent on the physiological state. A proportional bias was observed comparing TRUST and SBO. The results suggested caution for inter-subject comparison of absolute SvO2 measurements using either TRUST or SBO.


Oral

What's New in the Spinal Cord?

Room 518A-C
Monday 16:00 - 18:00
Moderators: Jiwon Oh
297
16:00
Investigating tissue microstructure using NODDI and histology: A chronic injury study on ex vivo macaque spinal cords
Andrew Bauman1,2, Andrew Yung1,2, Jie Liu3, Junhao Liu4, Qingan Zhu4, Piotr Kozlowski1,2,3, and Wolfram Tetzlaff3

1Radiology, University of British Columbia, Vancouver, BC, Canada, 2UBC MRI Research Centre, Vancouver, BC, Canada, 3International Collaboration on Repair Discoveries, Vancouver, BC, Canada, 4Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China

In this study we sought to understand whether Neurite Orientation Dispersion and Density Imaging (NODDI) could accurately delineate the extent of microstructure damage in an ex-vivo macaque spinal cord. We used histology as a gold standard for delineating the margin between damaged and undamaged tissue. Qualitative analysis exposed disagreements between NODDI maps and histology in areas of damage. This suggests that NODDI may not be appropriate for this model of chronic spinal cord injury.

298
16:12
Finger-Tapping Task fMRI in the Human Cervical Spinal Cord at 7T
Alan C Seifert1,2,3,4, Yazhuo Kong4,5, Karla L Miller4, Irene Tracey4, and S Johanna Vannesjo4

1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 3Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 4Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 5Institute of Psychology, Chinese Academy of Sciences, Beijing, China

Functional MRI of the spinal cord is challenging due to its small size and deep anatomical location. Increasing field strength enhances BOLD signal and improves SNR, but B0 distortions produced by the lungs and vertebral column are amplified, presenting additional challenges in protocol optimization.  Barry et al. have successfully performed resting-state fMRI at 7T; here, we present observations of robust, well-localized motor task activation in the human cervical spinal cord at 7T. We assessed single-shot and multi-shot EPI at two different resolutions.  Multi-shot EPI achieved finer resolution and less spatial distortion in this preliminary 7T spinal cord task fMRI study.

299
16:24
Advanced Magnetic Resonance techniques in Post-Mortem Human Spinal Cord Injury: Correlations with Histopathology
Sarah R. Morris1,2,3, Valentin Prevost1,2, Piotr Kozlowski1,2,3,4, Andrew Yung1,2,4, Andrew Bauman1,2,4, Zahra Samadi B.1,5, Caron Samadi Fournier1,5, Allan Aludino1,6, Lisa Parker7, Kevin Dong1, Femke Streijger1, G. R. Wayne Moore1,5,8, Brian Kwon1,6, and Cornelia Laule1,2,3,5

1International Collaboration on Repair Discoveries, Vancouver, BC, Canada, 2Radiology, University of British Columbia, Vancouver, BC, Canada, 3Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 4UBC MRI Research Centre, Vancouver, BC, Canada, 5Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada, 6Vancouver Spine Surgery Institute, Vancouver, BC, Canada, 7Vancouver General Hospital, Vancouver, BC, Canada, 8Medicine, University of British Columbia, Vancouver, BC, Canada

Spinal cord injury prognosis assessments rely on subjective clinical evaluations and often poorly predict outcome; quantitative imaging biomarkers for spinal cord injury evaluation would aid clinical decision making. Our study applied two advanced MRI techniques to the imaging of post-mortem human spinal cord injury samples. We compared in-homogeneous magnetisation transfer and NODDI metric maps with six histological stains to relate the MR image contrast to biological correlates. We found a correlation trend between ihMT signal with strong T1D-filtering and Luxol Fast Blue optical density (myelin phospholipid stain) in white and grey matter.

300
16:36
Cervical Spine inhomogeneous Magnetization Transfer (ihMT) Imaging Using ECG-Triggered 3D Rapid Acquisition Gradient-Echo (ihMT-RAGE)
Thomas Troalen1, Virginie Callot2,3, Gopal Varma4, Arash Forodighasemabadi2,3, Maxime Guye2,3, David C Alsop4, Guillaume Duhamel2,3, and Olivier M Girard2,3

1Siemens Healthcare SAS, Saint-Denis, France, 2Aix-Marseille Univ, CNRS, CRMBM, Marseille, France, 3APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France, 4Radiology, Division of MR research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States

Inhomogeneous magnetization transfer (ihMT) is a promising MRI modality that provides high sensitivity and specificity to myelinated tissue. Demyelinating pathologies in the central nervous system could then be addressed by this technique. The goal of this work is to demonstrate that the combination of ihMT preparation with Rapid Acquisition Gradient Echo (ihMT-RAGE), as recently proposed for the brain, can be adapted to an ECG-triggered 3D exploration of the cervical spinal cord within a clinically-compatible scan time. The in-vivo ihMT results from healthy cervical spinal cord demonstrate the great potential of the ihMT-RAGE technique for future investigations of degenerative spinal cord pathologies.

301
16:48
Intra-Voxel Incoherent Motion at 7T to quantify human spinal cord microperfusion: pitfalls and promises
Simon Levy1,2,3,4, Stanislas Rapacchi1,2, Aurélien Massire1,2,4, Thorsten Feiweier5, Maxime Guye1,2, Thomas Troalen6, and Virginie Callot1,2,4

1Faculty of Medicine, Aix-Marseille Univ, CNRS, CRMBM, Marseille, France, 2APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France, 3Faculty of Medicine, Aix-Marseille Univ, IFSTTAR, LBA, Marseille, France, 4iLab-Spine International Associated Laboratory, France-Canada, Marseille-Montreal, France, 5Siemens Healthcare GmbH, Erlangen, Germany, 6Siemens Healthcare SAS, Saint-Denis, France

Spinal cord microperfusion assessment in human is challenging but would greatly help characterize tissue integrity and surgery decision-making. Intra-Voxel Incoherent Motion (IVIM) microperfusion measurement is promising but remains highly Signal-to-Noise ratio (SNR) demanding. Monte-Carlo simulations show that IVIM two-step segmented fitting approach is less accurate than directly fitting the bi-exponential representation to all b-values. Simulations also help quantify required SNR and estimation errors to measure IVIM parameters in the context of low perfusion. Exploiting 7T SNR gain, large number of repetitions and group average, IVIM was able to unveil the gray matter higher microperfusion-related pattern, compared to white matter, in agreement with brain studies.

302
17:00
Cervical spinal cord diffusion MRI and intraspinal space restriction at the occipito-cervical junction in mucopolysacharidoses patients
Igor Nestrasil1,2, Rene Labounek1,3, Carol Nguyen1, Ivan Krasovec1, Jan Valosek3,4, Alena Svatkova1,5, Julien Cohen-Adad6, Christophe Lenglet2, and Chester Whitley1

1Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States, 2Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 3Department of Neurology, Palacky University, Olomouc, Czech Republic, 4Department of Biomedical Engineering, University Hospital Olomouc, Olomouc, Czech Republic, 5Department of Medicine III, Clinical Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria, 6Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada

The overall goal of this project is to establish novel MRI parameters for reliable detection of cervical spinal cord (CSC) microstructural abnormalities in patients with Mucopolysaccharidosis (MPS) that develop prior to the clinical manifestation of spinal cord damage. Quantitative analysis of diffusion MRI (dMRI) may characterize microstructural alterations of CSC with high sensitivity. In this study measures of CSC microstructure were determined by dMRI using a protocol based on the RESOLVE (REadout Segmentation Of Long Variable Echo trains) sequence. Derived diffusion metrics were then related to the anatomical measures of the cervical spine in patients with MPS.

303
17:12
A Multi-site/multi-scanner DTI study of the adult spinal cord
Devon M Middleton1, Joshua Fisher1, Adam E Flanders1, Feroze B Mohamed1, John H Woo2, Mark Elliot2, Scott H Faro3, and Laura Krisa1

1Thomas Jefferson University, Philadelphia, PA, United States, 2University of Pennsylvania, Philadelphia, PA, United States, 3Johns Hoplkins University, Baltimore, MD, United States

This study presents DTI data collected for the complete cervical and thoracic spinal cord in healthy adult subjects as part of a multi-site/multi-scanner study.  Thirty adult subjects were imaged with four different scanners including 1.5T and 3T field strengths and variability in DTI metrics was examined.

304
17:24
Column-specific microstructural changes in patients with non-myelopathic degenerative compression of the cervical spinal cord revealed by diffusion MRI
Jan Valošek1,2, René Labounek1,3, Tomáš Horák4,5, Alena Svátková4,6, Petr Kudlička4, Pavel Hok1, Jan Kočica4,5, Christophe Lenglet7, Petr Hluštík1, Josef Bednařík4,5, and Petr Bednařík4,8

1Department of Neurology, University Hospital Olomouc, Olomouc, Czech Republic, 2Department of Biomedical Engineering, University Hospital Olomouc, Olomouc, Czech Republic, 3Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States, 4Central European Institute of Technology, Masaryk University, Brno, Czech Republic, 5Department of Neurology, University Hospital Brno, Brno, Czech Republic, 6Department of Medicine III, Clinical Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria, 7Center for Magnetic Resonance Research, Minneapolis, MN, United States, 8High Field MR Centre, Medical University of Vienna, Vienna, Austria

While delineation of microstructural changes in white matter (WM) columns of cervical spinal cord (CSC) in patients with non-myelopathic degenerative CSC compression (NMDCSCC) remains a challenge for most current MRI techniques, High Angular Resolution Diffusion Imaging (HARDI) protocols promise to overcome this issue. Thus, our group utilized novel HARDI-ZOOMit protocol to extract metrics from diffusion tensor and ball-and-stick models in three major CSC columns. HARDI-ZOOMit protocol was able to detect column-specific significant differences between healthy controls and patients with NMDCSCC with more complex abnormalities in ventral CSC columns in C3-C6 levels.

305
17:36
Establishing a Relationship Between Pain and Spinal Cord Demyelination using Magnetization Transfer Imaging and Thermal Sensory Testing
Nadia Barakat1, Steven Staffa1, Leslie Benson2, Mark P Gorman2, David Zurakowski1, and David Borsook1

1Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Boston, MA, United States, 2Department of Neurology, Boston Children's Hospital, Boston, MA, United States

Myelitis is a demyelinating disorder of the spinal cord . It can occur as an isolated syndrome or in the context of an autoimmune condition such as MS. Pain is a significant problem in myelitis and has a major impact on treatment response and rehabilitation efforts. Magnetization Transfer Imaging has the ability to provide a marker for myelin content. Defining a relationship between pain and demyelination could lead to improved disease outcome. Our results showed significant differences in spinal cord MTR (C1 to T12) and pain (heat/cold stimuli) between patients and controls, and strong correlation between MTR and heat detection thresholds. 

306
17:48
Construction of a quantifiable rat spinal cord atlas and tract delineation using agglomerative clustering
Harris Nami1, Ariane Saliani1,2, Aldo Zaimi1, Tanguy Duval1,3, Christian Perone1, Nikola Stikov1,4, and Julien Cohen-Adad1,5

1NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada, 2Institute of Biomedical Engineering, University of Montreal, Montreal, QC, Canada, 3UMR 1214 Toulouse Neuroimaging Center, Institut national de la santé et de la recherche médicale, Toulouse, France, 4Montreal Heart Institute, Montreal, QC, Canada, 5Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada

With qMRI becoming the norm in obtaining quantitative values for most MRI studies, there is still a need for its validation as new techniques are constantly being implemented. With this in mind, we propose a matter microstructure atlas of the rat spinal cord based on high-resolution histology. This atlas contains morphometric data such as axon density, axon diameter and g-ratio. Furthermore, a clustering algorithm was implemented to generate white matter tracts delineation based on axon morphometry, possibly leading to an improvement on outdated atlases. The proposed atlas is open access and can be used for quantitative comparisons with qMRI studies.


Oral

Quantitative Parameter Mapping

Room 520A-F
Monday 16:00 - 18:00
Moderators: Philipp Ehses & Rahel Heule
307
16:00
MANTIS: Model-Augmented Neural neTwork with Incoherent k-space Sampling for accelerated MR parameter mapping
Fang Liu1, Li Feng2, and Richard Kijowski1

1Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, United States

The purpose of this work was to develop and evaluate a novel deep learning-based reconstruction framework called Model-Augmented Neural neTwork with Incoherent k-space Sampling (MANTIS) for accelerated MR parameter mapping. Our approach combines end-to-end CNN mapping with k-space consistency using the concept of cyclic loss to further enforce data and model fidelity. Incoherent k-space sampling is used to improve reconstruction performance. A physical model is incorporated into the proposed framework, so that the parameter maps can be efficiently estimated directly from undersampled images. The performance of MANTIS was demonstrated for T2 mapping of the knee joint. Our study demonstrated that the proposed MANTIS framework represents a promising approach for efficient MR parameter mapping. MANTIS can potentially be extended to other types of parameter mapping with appropriate models.

308
16:12
Three-Dimensional Whole Brain Simultaneous T1, T2, and Apparent Diffusion Coefficient Mapping Using MR Multitasking
Sen Ma1,2, Anthony G Christodoulou2, Christopher T Nguyen2,3, Fei Han4, Nan Wang1,2, Yibin Xie2, and Debiao Li1,2

1Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, United States, 2Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States, 3Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States, 4Siemens Healthcare, Los Angeles, CA, United States

Three-dimensional, multi-parametric quantitative mapping of relaxation and diffusion parameters is desirable for many clinical imaging application, including the diagnosis and follow-up assessment of tumors. Traditionally, this is performed by separate scans which are time-consuming. We propose a novel Multitasking framework to achieve 3D whole-brain simultaneous T1/T2/ADC mapping in ~9min. The underlying multidimensional image is modeled as a low-rank tensor, with a time-resolved phase correction technique to compensate for the phase inconsistency induced by pulsatile motion during diffusion preparation. T1/T2/ADC measurements in healthy volunteers agree with reference methods, yielding intraclass correlation coefficients > 0.80 for both gray and white matter.

309
16:24
Magnetization transfer (MT) of human brain at 7T in the context of a 3D multi-parameter mapping protocol
Hampus Olsson1, Mads Andersen2,3, Jimmy Lätt4,5, Ronnie Wirestam1, and Gunther Helms1,3

1Clinical Sciences Lund, Medical Radiation Physics, Lund University, Lund, Sweden, 2Philips Danmark A/S, Philips Healthcare, Copenhagen, Denmark, 3National 7T Facility, Lund University, Lund, Sweden, 4Centre for Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden, 5Clinical Sciences Lund, Department of Radiology, Lund University, Lund, Sweden

3D multi-gradient echo MRI can be used to estimate T1, T2*, PD and the magnetization transfer (MT), which is increasingly used for multi-parametric mapping (MPM) of human brain. The increased polarization at 7T compared to lower B0 allows for increased spatial resolution or reduced scan times. However, SAR restrictions imposed on the MT pulse and B1 inhomogeneity pose challenges. In this work, we propose a protocol for MPM of human brain at 7T with special attention paid to eliminating bias when mapping MTsat while obtaining submillimeter isotropic spatial resolution in under 12 minutes with acceptable SNR.

310
16:36
Echo Planar Time-Resolved Imaging (EPTI) with subspace constraint and optimized k-t trajectory
Zijing Dong1,2, Fuyixue Wang1,3, Timothy G. Reese1, Berkin Bilgic1, and Kawin Setsompop1,3

1A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Electrical Engineering and Computer Science, MIT, Cambridge, MA, United States, 3Harvard-MIT Health Sciences and Technology, MIT, Cambridge, MA, United States

Echo planar time-resolved imaging (EPTI) is a multi-contrast quantitative imaging technique, which achieved fast acquisition of distortion- and blurring-free images at multiple echo times (TE). To improve the SNR and accuracy of EPTI at high-accelerations, in this study, we developed a subspace-constrained reconstruction for EPTI and proposed new k-t sampling trajectories to take advantage of this reconstruction. The subspace reconstruction is also augmented with phase-cycling to extract high-resolution phase data, without need of high-resolution B0 calibration scan. Using the proposed approach, whole-brain 1.1mm-isotropic multi-echo images, and T2* and B0 maps are reconstructed from 3D-EPTI data acquired within 50 seconds. 

311
16:48
Loss Adaptive Dipole Inversion (LADI): A novel data driven approach for quantitative susceptibility mapping
Srikant Kamesh Iyer1, Brianna Moon2, Rishab Kumar3, and Walter R.T Witschey1

1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Bioengineering, University of Pennsylvania, Philadelphia, PA, United States, 3Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA, United States

This abstract presents a novel data driven approach for high quality QSM reconstructions without the use of complex and computationally intensive reconstruction models. The purpose of this approach is to develop a reconstruction technique which does not depend on the use of spatial priors from the magnitude image to remove artifacts and reduce blurring of edges. In our proposed formulation, the data fidelity term is updated based on the deviation of the estimated susceptibility map from the measured local field. With the proposed fidelity-loss adaptive reconstruction formulation, removal of artifacts was achieved without causing smoothing of sharp features.

312
17:00
T2-gSlider: rapid high resolution T2 mapping with generalized SLIce Dithered Enhanced Resolution and model-based reconstruction
Xiaozhi Cao1, Congyu Liao2,3, Siddharth Srinivasan Iyer3,4, Hongjian He1, Kawin Setsompop2,3, Jianhui Zhong1,5, and Berkin Bilgic2,3

1Center for Brain Imaging Science and Technology, Department of Biomedical Engineering, Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, China, 2Department of Radiology, Harvard Medical School, Charlestown, MA, United States, 3Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 4Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, 5Department of Imaging Sciences, University of Rochester, Rochester, NY, United States

To obtain rapid high isotropic resolution whole-brain T2 maps, a T2 generalized Slice-dithered enhanced resolution (T2-gSlider) acquisition/reconstruction framework is proposed. An accelerated RF-encoded multi-slab, multi-shot SE-EPI acquisition with variable TEs was developed to obtain high SNR acquisitions with reduced TR. A structured low-rank constraint was applied to reconstruct highly undersampled multi-shot data and achieve robust reconstruction for each slab. A Bloch simulated subspace shuffling model was utilized for T2 quantification and incorporated into gSlider reconstruction to further accelerate the acquisition. The proposed framework is demonstrated to enable whole-brain 1mm isotropic T2 mapping in ~40 seconds.

313
17:12
Towards robust – and accurate – QSM in cortical and sub-cortical regions of the human brain at 9.4T: the influence of masking
Gisela E Hagberg1,2, Elisa Tuzzi1, Joana Loureiro1, Thomas Ethofer1,3, Rolf Pohmann4, Jonas Bause4, Pascal Martin5, Marina Pavlova3, Marc Himmelbach6, Anja Zeller3, Christoph Laske3, Andreas J Fallgatter3, and Klaus Scheffler1,4

1Biomedical Magnetic Resonance, University Hospital Tübingen, Tübingen, Germany, 2High Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 3Psychiatry and Psychotherapy, University Hospital Tübingen, Tübingen, Germany, 4Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 5Neurology and Epileptology, Hertie Institute for Clinical Brain Research, Tübingen, Germany, 6Neuropsychology, Hertie Institute for Clinical Brain Research, Tübingen, Germany

Quantitative susceptibility mapping (QSM) targets a fundamental MR-parameter but is problematic due to the presence of a strong background and local field variations. These may cause multiple phase wraps which are particularly prominent at high fields and long echo-times. We propose automated tissue masking excluding brain areas with excessive phase wraps and show how this approach can improve the quality of QSM. Performance was evaluated with regard to iron quantification in subcortical and cortical areas, and was compared with R2* maps in the same 21 subjects aged 19-56y and literature values.

314
17:24
Model-based reconstruction for simultaneous multi-slice T1 mapping using single-shot inversion-recovery radial FLASH
Xiaoqing Wang1, Sebastian Rosenzweig1, Nick Scholand1, H. Christian M. Holme1, and Martin Uecker1

1Department of Interventional and Diagnostic Radiology of the University Medical Center Göttingen, Göttingen, Germany

Recent advances in real-time MRI and model-based reconstructions have enabled single-slice T1 mapping within a single inversion recovery. To allow fast multi-slice T1 mapping, this work employs radial simultaneous multi-slice (SMS) schemes and develops an SMS model-based reconstruction approach for high-resolution multi-slice T1 mapping based on single-shot inversion recovery FLASH. In comparison to conventional multi-slice approaches, the proposed SMS model-based reconstruction achieves high resolution (0.75 x 0.75 x 5 mm3) T1 maps for three slices of the brain within 4 s with a higher precision and a better preservation of image details.

315
17:36
Whole-brain 3D multi-parametric quantitative extraction at 7T using parallel transmission Universal Pulses
Lisa Leroi1, Vincent Gras1, Ludovic de Rochefort2, Mathieu D. Santin3,4, Romain Valabrègue3,4, Franck Mauconduit5, Denis Le Bihan1, Nicolas Boulant1, and Alexandre Vignaud1

1CEA - Neurospin, Gif-sur-Yvette, France, 2CRMBM/UMR 7339 CNRS, Aix Marseille Université, Marseille, France, 3CENIR, ICM, Paris, France, 4Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France, 5Siemens Healthineers, Saint-Denis, France

Performing simultaneous quantitative MRI at ultra-high field is challenging, as B0 and B1 heterogeneities, and Specific Absorption Rate increase with field strength. In this work, Quantitative Imaging using Configuration States is successfully applied in vivo at 7T using calibration-free parallel transmission Universal Pulses to retrieve 3D whole-brain M0, flip angle, T1 and T2 maps in a clinically-relevant time. The method relies on the acquisition of multiple contrasts with spoiled SSFP sequence by varying flip angle and radiofrequency spoiling in a limited and optimized number of sets. Quantification of the physical parameters was then performed by fitting acquired data to the Bloch-Torrey equation.

316
17:48
Single Breath-Hold T2 Quantification utilizing a Spiral Multi-Contrast TSE Sequence
Naoharu Kobayashi1 and Michael Garwood1

1Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States

A single breath-hold multi-contrast TSE sequence with spiral k-space sampling is introduced for T2 quantification. Sparsity constraint image reconstruction was applied to reconstruct undersampled datasets acquired under single breath-holding. The feasibility of the proposed sequence and image reconstruction were tested in brain and thoracic imaging for normal volunteers. The proposed method achieved T2 quantification of the thoracic region without clear cardiac motion artifacts.


Oral

QSM & ETM

Room 710B
Monday 16:00 - 18:00
Moderators: Xu Li & Sina Straub
317
16:00
On the linearity of deep neural network trained QSM
Woojin Jung1, Jaeyeon Yoon1, Joon Yul Choi1, Eung-Yeop Kim2, and Jongho Lee1

1Department of Electrical and Computer Engineering, Seoul National University, Seoul, Korea, Republic of, 2Department of Radiology, Gachon University, Incheon, Korea, Republic of

In this work, the linearity property of a recently proposed neural network-based QSM is explored. The QSMnet, which was trained using healthy volunteers, was quantitatively evaluated for patients with hemorrhage whose susceptibility values were outside of the trained range. The results showed that the QSMnet underestimated the susceptibility in hemorrhage, breaking linearity between true susceptibility and QSMnet-generated susceptibility. To overcome this limitation, we developed a linear scaling method that generalized the network for a wider range of susceptibility. The new network successfully reconstructed the patient data with good linearity results.

318
16:12
Separating intra- and extra-axonal susceptibility effects using a Diffusion-Filtered Asymmetric Spin Echo (D-FASE) sequence
Elena Kleban1, Chantal M W Tax1, Umesh S Rudrapatna1, Derek K Jones1,2, and Richard Bowtell3

1Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff, UK, Cardiff, United Kingdom, 2School of Psychology, Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia, 3Sir Peter Mansfield Imaging Centre, School of Physiscs and Astronomy, University of Nottingham, Nottingham, UK, Nottingham, United Kingdom

The investigation of brain white matter is a key area of application of MRI, with much effort focused on using MR techniques to  quantify tissue microstructure. Here, we bring together two complementary approaches that are commonly used to probe tissue microstructure (signal dephasing due to: (i) diffusion and (ii) microscopic susceptibility effects) using a novel Diffusion-Filtered Asymmetric Spin Echo (D-FASE) technique. Using D-FASE we can separately assess the evolution of the intra- and extra-axonal signals under the action of susceptibility effects, revealing differences in the behaviour in fibres that are parallel and perpendicular to B0.

319
16:24
VaNDI: Variational Nonlinear Dipole Inversion enables QSM without free parameters
Daniel Polak1, Itthi Chatnuntawech2, Jaeyeon Yoon3, Siddharth Srinivasan Iyer1, Kawin Setsompop1, and Berkin Bilgic1

1Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2National Nanotechnology Center, Pathum Thani, Thailand, 3Department of Electrical and Computer Engineering, Seoul National University, Seoul, Korea, Democratic People's Republic of

We propose Nonlinear Dipole Inversion (NDI) for high-quality Quantitative Susceptibility Mapping (QSM) without additional regularization, while matching the RMSE of state-of-the-art regularized reconstruction techniques. In addition to avoiding over-smoothing these techniques often face, we also obviate the need for parameter selection. NDI is flexible enough to allow for reconstruction from an arbitrary number of head orientations, and outperforms COSMOS using as few as 2-direction data. This is made possible by a nonlinear forward-model that uses the magnitude as an effective prior, for which we derived a simple gradient descent update. We synergistically combine this physics-model with Variational Networks (VN) to leverage the power of deep learning in the VaNDI algorithm. VaNDI adopts this simple gradient descent rule and learns the network parameters during training, hence requires no additional parameter tuning.  

320
16:36
U2-Net for DEEPOLE QUASAR–A Physics-Informed Deep Convolutional Neural Network that Disentangles MRI Phase Contrast Mechanisms
Thomas Jochmann1, Jens Haueisen1, Robert Zivadinov2,3, and Ferdinand Schweser2,3

1Department of Computer Science and Automation, Technische Universität Ilmenau, Ilmenau, Germany, 2Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY, United States, 3Clinical and Translational Science Institute, University at Buffalo, Buffalo, NY, United States

Magnetic susceptibility is a physical property of tissues that changes with iron level and (de-)myelination. Mapping the susceptibility can help us improve our understanding of the brain and its diseases, such as multiple sclerosis and Alzheimer disease. Quantitative Susceptibility Mapping (QSM) derives the susceptibility using MRI phase data. QUASAR adds a more sophisticated physical model to QSM. Our novel U2-Net for DEEPOLE QUASAR uses deep learning to separate the magnetic field into two components from different contrast mechanisms, yields an improved susceptibility map, and shows where in the brain the tissue does not adhere to the basic QSM model, e.g. due to microstructural anisotropy.

321
16:48
Deep Learning for solving ill-posed problems in Quantitative Susceptibility Mapping – What can possibly go wrong?
Pia Christine Høy1, Kristine Storm Sørensen1, Lasse Riis Østergaard1, Kieran O'Brien2,3, Markus Barth2, and Steffen Bollmann2

1Department of Health Science and Technology, Aalborg University, Aalborg, Denmark, 2Centre for Advanced Imaging, The University of Queensland, Brisbane, Australia, 3Healthcare Pty Ltd, Siemens, Brisbane, Australia

Quantitative susceptibility mapping (QSM) aims to solve an ill-posed field-to-source inversion to extract magnetic susceptibility of tissue. QSM algorithms based on deep convolutional neural networks have shown to produce artefact-free susceptibility maps. However, clinical scans often have a large variability, and it is unclear how a deep learning-based QSM algorithm is affected by discrepancies between the training data and clinical scans. Here we investigated the effects of different B0 orientations and noise levels of the tissue phase on the final quantitative susceptibility maps.

322
17:00
One-Dimensional k-Space Metrics on Cone Surfaces for Quantitative Susceptibility Mapping
Maximilian N. Diefenbach1, Christof Böhm1, Jakob Meineke2, Chunlei Liu3, and Dimitrios C. Karampinos1

1Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany, 2Philips Research, Hamburg, Germany, 3Department of Electrical Engineering and Computer Sciences, & Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States

An important question in QSM is how to compare different QSM reconstructions. We propose new metrics to compare susceptibility maps on cone surfaces in the Fourier domain following the intrinsic geometry of the dipole kernel. This physically motivated approach augments the idea of previously proposed error spectrum plots in MRI image reconstruction to specifically suit the QSM dipole inversion. The novel metrics complement previous metrics used in the 2016 QSM reconstruction challenge.

323
17:12
Free lunch may not exist, but free contrast does: Calculation of Susceptibility weighted Imaging contrast from data obtained for MR Elastography
Yogesh kannan Mariappan1, Jaladhar Neelavalli1, and Nehul Kishorbhai Makani1,2

1Philips Healthcare, Bengaluru, India, 2Indian Institute of Technology, Madras, India

In typical phase contrast based MR imaging studies like MR Elastography, the phase of interest is extracted from the data and is used in downstream processing to calculate the relevant clinical parameters of interest. While the background phase is typically discarded, we explored the feasibility of obtaining other relevant contrast like SWI contrast from this background phase. This indeed provides useful independent information and we provide evidence on a phantom and in-vivo human experiments. For example, SWI contrast obtained from MRE data of the brain improves the visualization of diamagnetic choroid plexus and paramagnetic internal cerebral veins.

324
17:24
Artifact free direct conductivity reconstruction method using the Dual Loop and artificial neural network with one current injection in MREIT.
Saurav Zaman Khan Sajib1, Munish Chauhan1, and Rosalind J Sadleir1

1School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, United States

Most the image reconstruction algorithms in magnetic resonance electrical impedance tomography (MREIT) and diffusion tensor magnetic resonance electrical impedance tomography (DT-MREIT) require at least two independent current patterns to uniquely reconstruct conductivity distributions. However, in transcranial electrical current stimulation (tES) or deep brain stimulation (DBS) only one current injection data is available. We applied Kirchhoff’s voltage law (KVL) in a mimetic discretized network, additional current data obtained from a computational model, and a radial basis function artificial neural network (RBF-ANN) approach, to demonstrate that it is possible to reconstruct the conductivity images using a single experimental current administration.

325
17:36
Concurrent mapping of electric currents and neurophysiological changes during Transcranial Direct Current Stimulation (tDCS)
Mayank Jog1,2, Kay Jann1, Lirong Yan1, and Danny JJ Wang1

1USC Stevens Neuroimaging and Informatics Institute, Los Angeles, CA, United States, 2UCLA Neurology, Los Angeles, CA, United States

Transcranial Direct Current Stimulation(tDCS) is a non-invasive neuromodulation technique that uses milliampere currents (applied at the scalp) to modulate cortical excitability. Although tDCS has been shown to improve clinical symptoms in depression, stroke rehabilitation and pain, the exact mechanism of tDCS is not yet fully understood. To help advance the study of tDCS mechanisms, we developed a novel technique that, for the first time, enables concurrent mapping of (i) the applied electric current and (ii) the neurophysiological changes induced in-vivo. In this work, we demonstrate the feasibility as well as reliability of this novel technique through phantom and in-vivo experiments. 

326
17:48
Deep Learning based MR Electrical Properties Tomography
Stefano Mandija1,2, Ettore F. Meliadò1,2, Niek R.F. Huttinga1,2, Peter R. Luijten1,2, and Cornelis A.T. van den Berg1,2

1University Medical Center Utrecht, Utrecht, Netherlands, 2Utrecht University, Utrecht, Netherlands

The inability of Magnetic Resonance Electrical Properties Tomography to accurately reconstruct tissue electrical properties severely limits its clinical use, e.g. as a biomarker in oncology. We demonstrate that the electrical properties reconstruction problem can be casted as a supervised deep learning task. Deep learning based electrical properties reconstructions for simulations and MR measurements (3 Tesla) on phantoms and human brains demonstrate great improvement in the quality of reconstructed electrical properties maps. This could be major step forward to turn electrical properties tomography into a reliable biomarker where pathological conditions can be revealed and characterized by abnormalities in tissue electrical properties.


Member-Initiated Symposium

Non-Contrast Cardiac MR Assessment of Ischemic Heart Disease

Organizers: Gabriele Bonanno, Sonia Nielles-Vallespin, Michael Salerno
Room 516AB
Monday 16:00 - 18:00
(no CME credit)
16:00
Myocardial Arterial Spin Labeling (ASL) Perfusion Imaging
Krishna Shrinivas Nayak1

1Electrical Engineering, University of Southern California, Los Angeles, CA, United States

16:24
T1 Relaxometry: Stress T1-Mapping for the Detection of Cardiac Ischemia
Vanessa Ferreira

16:48
T2 Relaxometry: Cardiac BOLD MRI & Stress MRI With CO2 Ventilation
Rohan Dharmakumar

17:12
Coronary Endothelial Function (CEF) Assessment with MRI
Allison Hays

17:36
Future Horizons in Non-Contrast Functional CMR
Sebastian Kozerke1

1ETHZ, Zurich, Switzerland


Member-Initiated Symposium

Frontiers & Challenges in Rodent Brain Imaging

Organizers: Elaine Bearer
Room 513A-C
Monday 16:00 - 18:00
(no CME credit)
16:00
Imaging How Early Life Stress Alters Brain Activity in the Adult & Its Response to Fear & Evolution
Daniel Barto

16:15
Imaging Cerebral Interstitial Flow by MRI in Rodent Brains: Effect of Evolving Cerebral Amyloid Angi
Helene Benveniste1

1Yale University, New Haven, United States

16:30
Imaging Cerebral Interstitial Flow by MRI in Rodent Brains: Effect of Evolving Cerebral Amyloid Angi
Hedok Lee

16:45
Multimodal Integrative Imaging of Amyloid Lesions: Gadolinium Staining of Amyloid Plaques & 3D Histo
Marc Dhenain

17:00
Neurovascular Phenotyping: The Next Frontier
Arvind Pathak1

1Radiology, Johns Hopkins University School of Medicine, MD, United States

17:15
Awake Rat Brain Imaging with a Focus on Forebrain Connectomics: Optogenetics & MRI
Nanyin Zhang

17:30
Biological Basis of Structural Covariance in the Mouse
Yohan Yee


Digital Poster: Spectroscopy & Non-Proton MR
Exhibition Hall
Monday 17:00 - 18:00
(no CME credit)
Study Group Business Meeting

Detection & Correction of Motion in MRI & MRS Study Group Business Meeting

Room 511A
Monday 17:00 - 18:00
(no CME credit)


Tuesday, 14 May 2019

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Sunrise Session

Connectivity for Clinical Study

Organizers: Masaaki Hori, Ivana Drobnjak, Dmitry Novikov
Room 510A-D
Tuesday 7:00 - 8:00
Moderators: Toshiaki Taoka & Masaaki Hori

Sunrise Session

Imaging Without Gadolinium: CEST

Organizers: Pia Maly Sundgren, Elna-Marie Larsson, Robert Witte
Room 511BCEF
Tuesday 7:00 - 8:00
Moderators: Xiang Xu & Robert Witte
7:00
CEST Technique
Linda Knutsson

7:30
Clinical Application of CEST
Daniel Paech

8:00
Adjournment


Sunrise Session

Multinuclear Imaging & Spectroscopy: Hyperpolarized 13C Use in Clinical Research & Trials

Organizers: Yi-Fen Yen, Malgorzata Marjanska, Catherine Hines
Room 512A-H
Tuesday 7:00 - 8:00
Moderators: Albert Chen & Kim Connelly
7:00
Clinical Polarizer, Sterilization & Clinical Coils
Daniel Vigneron

7:20
Applications in Clinical Cancer Research
Ferdia Gallagher

7:40
Applications in Clinical Cardiovascular Research
Damian Tyler

8:00
Adjournment


Sunrise Session

Preclinical MRI: Methods & Applications: Contrasts & Probes

Organizers: Ed Wu, Elena Vinogradov, Lucio Frydman, Damian Tyler, Elena Kaye
Room 513A-C
Tuesday 7:00 - 8:00
Moderators: Noam Shemesh & Elena Vinogradov
7:00
Exogenous & Endogenous Contrasts
Kannie WY Chan

7:30
Molecular & Cellular Probes
Peter Caravan

8:00
Adjournment


Sunrise Session

Quantitative MRI: Diffusion & Flow

Organizers: José Marques, Sebastian Kozerke, Ileana Hancu
Room 513D-F
Tuesday 7:00 - 8:00
Moderators: Rita Nunes & Sebastian Kozerke
7:00
Incoherent vs. Coherent Motion
Andreas Wetscherek

7:30
Sequences & Analysis
Magalie Viallon

8:00
Adjournment


Sunrise Session

MRI in Liver Transplantation

Organizers: Utaroh Motosugi, Mustafa Shadi Bashir, Claude Sirlin
Room 516AB
Tuesday 7:00 - 8:00
Moderators: Kathryn Fowler & Chang-Hee Lee
7:00
MRI in Living Donor Assessment
Kartik Jhaveri

7:30
MRI for Post-Liver Transplant Assessment
Alessandro Furlan

8:00
Adjournment


Sunrise Session

Advanced MSK MRI Acquisition & Post-Processing: Rapid Imaging

Organizers: Jung-Ah Choi, Miika Nieminen, Edwin Oei, Jan Fritz
Room 516C-E
Tuesday 7:00 - 8:00
Moderators: Noam Ben-Eliezer & Stefan Zbyn

Sunrise Session

Cardiovascular MR of the Future: Software

Organizers: Tim Leiner, Daniel Sodickson, Bernd Wintersperger
Room 518A-C
Tuesday 7:00 - 8:00
Moderators: Sonia Nielles-Vallespin & Alexander Raaijmakers

Digital Poster: General Cancer Imaging
Exhibition Hall
Tuesday 8:15 - 9:15
(no CME credit)
Digital Poster: Acquisition, Reconstruction & Analysis
Exhibition Hall
Tuesday 8:15 - 9:15
(no CME credit)
Study Group Business Meeting

Molecular & Cellular Imaging Study Group Business Meeting

Room 511A
Tuesday 8:15 - 9:15
(no CME credit)

Power Pitch

Pitch: The Aging Brain

Power Pitch Theater A - Exhibition Hall
Tuesday
Pitches: 8:15 - 9:15
Posters: 9:15 - 10:15
Moderators: Ricardo Alvarez-Tobian & Jung Hee Lee
(no CME credit)
327
Pitch: 8:15
Poster: 9:15
Plasma 1
Targeting brain and cognitive aging with multi-modal imaging and connectome topography profiling
Alexander J. Lowe1, Casey Paquola1, Reinder Vos de Wael1, Sara Lariviere1, Shahin Tavakol1, Benoit Caldairou2, Neda Bernasconi2, Andrea Bernasconi2, Nathan Spreng3, and Boris C. Bernhardt1

1Multimodal Imaging and Connectome Laboratory, Montreal Neurological Institute, Montreal, QC, Canada, 2Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute, Montreal, QC, Canada, 3Brain and Cognition Laboratory, Montreal Neurological Institute, Montreal, QC, Canada

We present an approach to represent and analyze age-related differences in cortical morphology and Aβ uptake based on connectome topography. Studying healthy individuals, we observed age-related reductions in neocortical thickness and atrophy across posterior hippocampal subfields. Additionally, we observed an interplay between aging effects and functional topography in both neocortical and hippocampal regions, with age-related thinning stronger towards unimodal regions and Aβ deposition increasing towards transmodal regions. Similarly, an inverted pattern of volume loss and Aβ deposition was observed along the hippocampal long-axis. Finally, imaging markers were found to predict cognitive performance in a topography-specific manner.

328
Pitch: 8:15
Poster: 9:15
Plasma 2
Age-related whole-brain structural changes in relation to cardiovascular risks
Tao Gu1,2, Hui Guo2,3, Min Chen1, and Xiaowei Song2,4

1Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, China, 2ImageTech Laboratory, Simon Fraser University, Surrey, BC, Canada, 3Department of Diagnostic Imaging, Tianjin Medical University General Hospital, Tianjin, China, 4Health Sciences and Innovation, Surrey Memorial Hospital, Fraser Health Authority, Surrey, BC, Canada

We investigated the relationship between structural brain health with age and cardiovascular risks across the adult life course. A score of the Brain Atrophy and Lesion Index (BALI), which assesses and integrates multiple changes commonly seen on MRI in the aging brain, was generated for each subject from evaluation of T2-weighted MRI. Our data showed that the accumulation of MRI detectable deficits in the brain became evident even in younger adults. Cardiovascular risks strongly affected the whole-brain structural health, in addition to the effect of age.


329
Pitch: 8:15
Poster: 9:15
Plasma 3
Differential developmental trajectory of magnetic susceptibility in healthy rhesus macaque brain
Jing Wu1, Hui Zhang2, Yongquan Ye3, Shuheng Zhang2, Qiang He2, Xintian Hu1, and Nan-jie Gong4

1Kungming istitute of zoology, Chinese Academy of Sciences, Kunming, China, 2Shanghai United Imaging Healthcare, Shanghai, China, 3UIH American Inc., Houston, Armenia, 4Shanghai Research Center for Brain Science and Brain-Inspired Intelligence, Shanghai, China

Myelination and iron deposition in the deep brain nuclei evolve both spatially and temporally. In this study, we quantitatively evaluated the change of iron content along with age in primate brains using quantitative susceptibility mapping (QSM). All the brain images were acquired from 23 healthy rhesus macaque monkeys (23+/-7.85 y, ranged 2 ~ 29 y) with a 3D five-echo GRE sequence. After analyzing susceptibility maps and R2* maps of the ROIs (including putamen, globus pallidus, caudate nucleus, thalamus, dentate nucleus, red nucleus, substantia nigra), susceptibility in most of the ROIs correlated with the growth of age significantly.

330
Pitch: 8:15
Poster: 9:15
Plasma 4
Age-related microstructural and physiological changes in normal brain assessed via anomalous diffusion derived γ, DTI, DKI and NODDI metrics
Michele Guerreri1,2, Marco Palombo3, Alessandra Caporale4, Emiliano Macaluso5, Marco Bozzali6, and Silvia Capuani2

1SAIMLAL, Sapienza University of Rome, Rome, Italy, 2Institute for Complex Systems, CNR, Rome, Italy, 3Department of Computer Science & Centre for Medical Image Computing, University College London, London, United Kingdom, 4Laboratory for Structural, Physiologic and Functional Imaging, Perelman S