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Saturday, May 7, 2016 Sunday, May 8, 2016 Monday, May 9, 2016 Tuesday, May 10, 2016 Wednesday, May 11, 2016 Thursday, May 12, 2016 Friday, May 13, 2016 Friday, May 6, 2016

Saturday, May 7, 2016

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Weekend Course

PET-MRI: Devices, Radiotracers & Applications

Organizers:Andrei H. Iagaru, M.D., Ryan Niederkohr, M.D., N. Jon Shah, Ph.D. & Greg Zaharchuk, M.D., Ph.D.

Room 324-326 7:30 - 18:00 Moderators:N.Jon Shah & Greg Zaharchuk

7:30
PET/MRI Scanner Overview

Jae Sung Lee

8:00
Attenuation & Motion Correction Strategies for PET Using PET/MRI

Attenuation correction (AC) for PET reconstruction using PET/MRI is not trivial.  MRI-based segmentation, atlas registration, and time-of-flight derived attenuation coefficients are most commonly applied and studied approaches for AC. Motion management of PET reconstruction, aided by the temporal resolution of MR-based signal, is promising, but still requires extensive investigation and robust method development.
Youngho Seo

8:30
Time-of-Flight: Do We Need It in PET/MRI?

The aim of this presentation is to introduce the participant into Time-of-Flight (ToF) Positron Emission Tomography. General concepts of ToF-PET, fundamental limits and most important characteristics of the key components scintillator and photo detector will be discussed. The correlation between timing resolution and image SNR, which is the main benefit of the timing measurement, will be introduced by means of examples from real patient examinations and simulations. Special emphasis will be put on completely new imaging application enabled by ToF-PET and on the potential of ToF-PET for simultaneous MR/PET imaging.
Christoph Lerche

9:00
Future Directions in PET/MRI

Craig Levin

9:30
Break & Meet the Teachers

10:00
PET Radiopharmacy 101

Frederick Chin

10:30
Radiation Safety & Procedures

Knowing how to protect oneself from radiation is an important aspect in the healthcare imaging workplace. Besides self-protection, knowledge about radiation can also aid healthcare professionals safeguard the health of their patients from excessive radiation. This talk serves to provide participants a basic understanding of ionizing radiation, X-rays  and radiobiology, as well as unravel the mystery of minimizing radiation doses in medical imaging.
S. Somanesan

11:00
Beyond FDG: New Tracers

PET/MRI has the potential to offer not just structure/function characterisation, but structure/function/tissue characterisation in a way that conventional CT combined with PET cannot provide. This talk will explore options beyond conventional FDG whole body PET/CT for detailed characterisation of the individual patient and their disease.
Dale Bailey

11:30
Regulatory Issues for Radiotracers around the World

This presentation will highlight the differences between PET radiopharmaceuticals and MRI contrast agents with respect to regulatory approval in order to educate those working with PET/MRI on the regulatory framework under which PET radiopharmaceuticals can be administered.
David Dick

12:00
Break & Meet the Teachers

13:30
Interpreting FDG PET images - a Crash Course

Eric Rohren

14:00
Clinical PET/MRI: Workflow Considerations

Marius Mayerhoefer

14:30
Oncological PET/MRI: Where Will it Replace PET/CT?

Thomas Hope

15:00
Cardiac PET/MRI

The development of hybrid PET/MRI imaging devices provides new perspectives in cardiovascular imaging. While these two imaging modalities (PET and MRI) have gained  well-established diagnostic value in clinical practice, the ability to acquire both modalities in a single session opens new perspectives in workflow and in assessment and quantitative evaluation of cardiovascular diseases. The development of new PET tracer will certainly add to the value of clinical applications of hybrid PET/MRI in the futur 
Osman Ratib

15:30
Pediatric PET/MRI

Jonathan McConathy

16:00
Break & Meet the Teachers

16:30
Role of PET/MRI in Brain Tumors

This presentation discusses the synergies that make MRI/PET a unique hybrid technology that could be used effectively to improve the diagnostic and prognostic information from each of its component modalities.
Fernando Boada

17:00
Brain Perfusion & Permeability Imaging

Educational Lecture to discuss on the clinical usefulness of combined use of PET and physiological imaging with MRI. Focus is set on chronic occlusive cerebrovascular diseases and malignant brain tumor.
Tadashi Nariai

17:30
Functional Imaging with PET/MRI

Among many potential applications of simultaneous PET and fMRI, this talk focuses on paradigms of function (fMRI) versus occupancy (PET) and combinations that investigate flow-metabolism coupling or oxygen versus glucose utilization. PET/fMRI can help clarifying aspects of receptor-based imaging using either drug or tasks that elevate neurotransmitter levels. The combined information has the potential to form new biomarkers with clinical utility. Metabolic imaging using PET in conjunction with fMRI measurements of CBF and CMRO2 can be done simultaneously within a single imaging session. This talk focuses on PET capabilities and possibilities for combining PET and fMRI information.
Joseph Mandeville

18:00
Adjournment & Meet the Teachers


Weekend Course

Molecular & Metabolic Imaging: Basic Concepts of Molecular Imaging

Organizers:Guanshu Liu, Ph.D. & Mark D. Pagel, Ph.D.

Room 300-302 8:30 - 12:00 Moderators:Kejia Cai & Leo Cheng

8:30
Relaxation Based Contrast Agents

This lecture will review the fundamental properties and applications of relaxation based contrast agents. We will begin by understanding the physics of relaxation and factors influencing it. With a view towards in vivo use, we will discuss the relevant physicochemical and MR properties that influence the success of relaxation based agents for biomedical applications.  We will also discuss factors that determine the pharmacokinetics of these agents and the opportunity for targeting tissue microenvironment. Finally we will review some new directions in the field outline future prospects.
Vikram Kodibagkar

9:15
Responsive Contrast Agents

Responsive contrast agents are a promising class of molecules for visualizing disease-relevant molecular events. These contrast agents undergo chemical changes in response to stimuli including enzyme activity, metal ion transport, and changes in pH and oxygen levels. The chemical changes lead to changes in contrast enhancement that can be detected with MRI. This talk will cover the basic principles behind how this class of contrast agents function and will highlight some published examples of response.
Matthew Allen

10:00
Break & Meet the Teachers

10:30
Chemical Exchange Saturation Transfer

This teaching presentation will attempt to demonstrate the power and existing present limitations of Chemical Exchange Saturation Transfer (CEST)-based MRI and its most prominent applications.
Xavier Golay

11:00
Multinuclear, Sodium & Fluorine

This presentation discusses the basic principles for the implementation and application of multi-nuclear MRI, with an emphasis on sodium MRI, in the study of disease in humans.
Fernando Boada

11:30
Fundamentals of Hyperpolarization

MRI relies on detecting signals in the radiofrequency range that are related to very small energy transitions of the spin ensemble. While this is a blessing with regard to the harmless character of the radiation, it imposes a serious problem in terms of the low sensitivity caused by almost vanishing spin polarization at ambient temperatures. Increasing the sensitivity through artificial enhancement of the net magnetization relies on so-called hyperpolarized agents for NMR and MRI. Hyperpolarization is a powerful technique that has enabled many varied applications for molecular and cellular imaging. This tutorial will summarize the methods of hyperpolarization, probe design and optimized signal encoding.

Leif Schröder

12:00
Lunch & Meet the Teachers


Weekend Course

An Update on Body MRI Protocols & Applications: Setting Up Your Body MRI Practice

Organizers: Lorenzo Mannelli, M.D., Ph.D., Ivan Pedrosa, M.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Room 331-332 8:00 - 10:00 Moderators:S. Sendhil Velan

8:00
Hardware, Patient Preparation, & Monitoring Considerations for Body MRI

In clinical body MRI, diagnostic radiologists often make choices in hardware, patient preparation or monitoring that impact workflow or image quality. In this session, we will review choices with potential effects in your day-to-day clinical practice and go through scenarios centered on body MR protocols.
Richard Do

8:30
Optimize Your MRI Sequences for Abdomen & Pelvis Examinations

The major factors that influence MR sequence optimisation for abdominal and pelvic exams will be outlined and discussed. Typical body and pelvic exams will be used to illustrate the key issues regarding selection of coils, imaging planes and sequence parameters.
David Lomas

9:00
Contrast Agents: Which one Should You Choose?

Objectives: 1.    To review chemical properties of commercially available gadolinium based contrast agents (GBCAs) 2.    To review applications of commercially available GBCAs 3.    To review current recommendations for safe use of GBCAs
Ruth Lim

9:30
Break & Meet the Teachers


Weekend Course

An Update on Body MRI Protocols & Applications: Diagnostic Approach to Focal Liver Lesions

Organizers:Ivan Pedrosa, M.D., Lorenzo Mannelli, M.D., Ph.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Room 331-332 10:00 - 11:00 Moderators:Hebert Alberto Vargas

10:00
MRI of Lesions in the Non-Cirrhotic Liver

Valerie Vilgrain

10:30
MRI Charaterization of Lesions in the Cirrhotic Liver

 The most frequent malignant tumor in cirrhotic liver is hepatocellular carcinoma (HCC). In a typical case, the imaging-based diagnosis of HCC is simple: hypervascular in arterial phase and washout in portal-venous/delayed phase. However, we often encounter atypical cases: hypovascular HCCs. Gadoxetic acid has advantage in hepatobiliary phase imaging, which helps distinguish HCC from pre-malignant lesion. “Hypovascular hypointense nodule in gadoxetic acid-enhanced MRI” is a new concept observed in cirrhotic patients, which suggests early HCC and develop hypervascular (typical) HCC subsequently. In this lecture, I will cover hypovascular HCCs with a special emphasis on “hypovascular hypointense nodule”.
Utaroh Motosugi


Weekend Course

An Update on Body MRI Protocols & Applications: Gastrointestinal

Organizers:Ivan Pedrosa, M.D., Lorenzo Mannelli, M.D., Ph.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Room 331-332 11:00 - 12:00 Moderators:Suraj Serai

11:00
MR Enterography

Jordi Rimola

11:30
Rectal CA Staging

Highlights ·        Use of MRI for rectal carcinoma staging and learn the clinical and therapeutic implications of rectal carcinoma  

Target Audience: Radiologists and MRI technicians.

Objectives: Understand the anatomical and pathological basis for MRI rectal carcinoma staging and its impact on therapeutic options.

Methods: Basic anatomy and pathology of rectal carcinoma will be introduced followed by case examples.       

 

Results: Participants will be able to understand the important anatomical and pathological MRI findings in rectal carcinoma.

Bertrand Ang

12:00
Lunch & Meet the Teachers


Weekend Course

Neuro 1: Stroke Triage

Organizers:Jonathan H. Gillard, M.D., FRCR, MBA, Jennifer A McNab, Ph.D. & Howard A Rowley, M.D.

Room 334-336 7:30 - 9:30 Moderators:Audrey Fan & Henk-Jan Mutsaerts

7:30
Stroke Triage: The Radiologist's Perspective

Acute ischemic stroke is a heterogeneous disease, with major stroke caused by proximal artery occlusions representing the stroke subtype with the most devastating outcomes.  With the recent success of the  endovascular clot retrieval  trials for major stroke, the primary role of the radiologist to identify the patients  suitable for treatment rapidly and accurately. The most common way to get this information is with non contrast CT, and CT angiography. In present clinical practice, time is dominant (<6hr) over physiology for decisions related to implementing therapy. There is evidence from the recent trials that it may be possible to extend the  selection criteria to include a larger group of patients that will still benefit from IA therapy. However, this will require clinical trials to demonstrate that  advanced imaging techniques to select these patients for treatment, leads to improved  outcomes.
Patricia Desmond

8:15
Stroke Triage: The Physicist's Perspective

The overall goal of this presentation is to provide a summary of the major unmet clinical needs in stroke imaging and management from a physicist’s perspective. Stroke imaging can broadly be considered in terms of (i) characterizing hemodynamic compensation mechanisms with the goal of stratifying treatments to prevent stroke, (ii) identifying viable tissue at risk for infarction in the setting of acute stroke, and (iii) evaluating chronic, post-stroke hemodynamic and neurochemical processes that may portend functional recovery. 
Manus Donahue

9:00
Panel Discussion

9:30
Break & Meet the Teachers


Weekend Course

Neuro 1: Tumor Tutorial

Organizers:Jonathan H. Gillard, M.D., FRCR, MBA & Jennifer A. McNab, Ph.D.

Room 334-336 10:00 - 12:00 Moderators:Stephen Price & Yi-Fen Yen

10:00
Tumor Tutorial: The Radiologist's Perspective

Different aspect of the problems facing the radiologist when evaluating brain tumours and the possible support of advance MR imaging methods as well as new imaging biomarkers will be presented..
Pia Maly Sundgren

10:30
Tumor Tutorial: The Physicist's Perspective

This presentation will review selected new techniques and applications for the imaging of human brain tumors, from the point of view of the MR physicist. A particular emphasis will be on metabolic MR neuroimaging techniques, including chemical exchange saturation transfer methods. The challenges involved in developing a new MR imaging technique for clinical use in humans will be considered.
Peter Barker

11:00
Tumor Tutorial: The Neuro-Oncologist's Perspective

Tham Chee Kian

11:30
Discussion

12:00
Adjournment & Meet the Teachers


Weekend Course

Physics for Physicists

Organizers:Thomas K. F. Foo, Ph.D. & N. Jon Shah, Ph.D.

Summit 1 8:30 - 17:30 Moderators:Seung-Kyun Lee & Ed Wu

8:30
MRI: The Classical Description

The NMR (Nuclear Magnetic Resonance) signal can be described classically by considering the motion of the net magnetisation (the vector sum of magnetic moments of individual nuclei). By considering individual isochromats – i.e. subsets of the spins that are behaving identically– we can visualise how the received signal will decay away due to T1, T2 and T2* relaxation. By additionally considering the effects of magnetic field gradients, we can spatially localise the signal, extending NMR to MRI (Magnetic Resonance Imaging). All these effects can be described by the Bloch equations, which give complete classical description of the behaviour of magnetisation.
Gareth Barker

9:00
MRI: A Systems Overview

· Basic understanding of how an MRI works can be achieved by comprehending its major functional subsystems.

· The subsystem currently experiencing the greatest innovation is RF transmission.

· Software defines the look and feel of the system and is the most important differentiator between systems.

Mark Ladd

9:30
Basic MR Safety (Magnetic Fields, Peripheral Nerve Stimulation, etc.)

Magnetic resonance techniques are considered to be not harmful. The three electromagnetic fields used for MR - static magnetic field, switched gradient fields, and radio frequency field - do not result in irreversible changes of human tissue, as long as certain limits are not exceeded. However, the applied fields show effects, which may cause severe hazards for patients, staff, and material, if MR examinations are not performed properly.
Harald Kugel

10:00
Break & Meet the Teachers

10:30
Bloch Equations & Typical MRI Contrast

Nikolaus Weiskopf

11:00
Sequences and Simulations

This presentation will provide an overview of the main gradient echo based (gradient spoiled, RF spoiled and balanced steady state free precession) and conventional/fast spin echo based pulse sequences and will illustrate some methods by which their behaviour can be simulated
Martin Graves

11:30
Pulse Sequence Check: Reality vs. Ideal

The effect of any pulse sequence on the magnetization in an object can be predicted very accurately using the Bloch equation. A general algebraic inversion of the Bloch equation is not possible and thus, the full set of object and system properties and parameters cannot be derived from measurement data directly. Using a few assumptions and neglecting possible deviations, the contrast of a given pulse sequence can be calculated and the spatial encoding can be inverted to reconstruct an image.
Oliver Speck

12:00
Lunch & Meet the Teachers

13:30
Basics of an EPI Acquisition

Echo Planar Imaging (1), or EPI, is a prototype for pulse sequences that sample two dimensions of K-space after a single excitation. 2D scanning after a single excitation means that signal modulations unrelated to applied gradient fields, such as transverse relaxation and resonance offsets, distribute across two dimensions in k-space and image space. EPI is highly demanding of gradient performance and fidelity. Gradient hardware advances have enabled the implementation of EPI, and continue to improve the utility and robustness of EPI. There are complex tradeoffs involved in the design of EPI pulse sequences and selection of EPI parameters with regard to gradient performance, SNR, image artifacts, ramp sampling, and other pulse sequence features.
Eric Wong

14:00
EPI Applications: What we Can See Using EPI as an Engine

Introduction to the uses of EPI as an acquisition ‘engine’ in advanced structural and functional pulse sequences · Overview of the principles of functional MRI, arterial spin labelling, diffusion imaging and chemical exchange saturation transfer imaging. · Description of the pulse sequence modules required to achieve these image contrasts. · Summary of the different flavours of each method, and the tricks required to minimize confounding artifacts.
Peter Jezzard

14:30
EPI Artifacts and Correections

Since its conception in 1977 echo planar imaging (EPI) remains famous for being a host of a variety of artefacts. Recent improvements in the gradient technology and the availability of receiver arrays offset some of the problems, which however was quickly counterbalanced by a general trend of increasing the main magnetic field strength and a common demand of increasing spatial resolution. Therefore understanding the physics behind the EPI artefacts continues to be important, as it allows one both to compose optimal protocols minimizing the possible damage at source and devise suitable post-acquisition strategies for correcting remaining imperfections.
Maxim Zaitsev

15:00
Break & Meet the Teachers

15:30
Diffusion Weighted Imaging & Applications

Diffusion-weighted imaging (DWI) makes use of molecular water motion to probe tissue microstructure. This lecture will focus on the basic principles of DWI acquisition. After introducing the most commonly used diffusion modules, the main acquisition challenges will be discussed.  Typical acquisition approaches will be presented, including single-shot and multi-shot sequences. Examples of frequent DWI image artefacts will be shown, and some of the approaches available for minimizing or correcting for their effect will be presented. The main applications of DWI to brain and body imaging will also be presented, focusing on stroke and lesion characterization.
Rita Nunes

16:00
Diffusion Tensor Imaging & Applications

The presentation will discuss, among others, the diffusion tensor model and diffusion indices, acquisition and data sampling strategies, validation of DTI and applications: tractography in neurosurgery, brain connectivity in vivo, gray matter structure and connectivity in fixed tissue.
Ana-Maria Oros-Peusquens

16:30
Beyond the Tensor Model

Diffusion tensor imaging (DTI) is widely employed to characterize diffusion anisotropy in multi-directional diffusion MR acquisitions. However, the DTI model has well-known limitations primarily because it assumes diffusion to be Gaussian. In this talk, DTI’s limitations will be discussed for three cases: (i) the presence of orientational complexity, (ii) nonlinearity of the signal decay curves, and (iii) dependence on the timing parameters of the sequence. Several alternative approaches will be outlined and it will be argued that a cost-benefit analysis has to be performed before abandoning the diffusion tensor model.
Evren Ozarslan

17:00
q-Space: What is it?

In this lecture the concepts behind q-space and q-space imaging will be reviewed. Starting from an historical overview on the major advances, the development of the q-space formalism and the concept of the diffusion propagator will be described and used to explain the origin of diffraction peaks and their possible application to infer pore sizes and other microstructural features. Q-space and Propagator based imaging techniques will then be introduced highlighting advantages and limitations of these techniques. Finally, the use of diffusion time as an new contrast to probe microstructure at different length scales will be discussed.
Flavio Dell'Acqua

17:30
Adjournment & Meet the Teachers


Weekend Course

MR Systems Engineering

Organizers:Thomas K. F. Foo, Ph.D. & Simone A. Winkler, Ph.D.

Summit 2 8:30 - 17:00 Moderators:Ergin Atalar & Simone Winkler

8:30
MR Systems Overview

A general overview of the Magnetic Resonance Imaging (MRI) system design is presented with focus on main subsystems, their desired properties and impacts on imaging system performance.
Saban Kurucay

9:00
Magnet Design, Manufacturing & Installation

Johannes Van Oort

9:30
Shimming: Superconducting & Passive Shims; Higher Order Shims & Application to Imaging

Having a homogeneous magnetic field is an essential requirement to ensure high image quality in MRI. Significant field inhomogeneity can result in severe signal losses or geometric distortions. To achieve the desired uniformity, effective and efficient shimming strategies are needed. Specifically, passive and active shimming strategies have been developed to correct for both the intrinsic and extrinsic magnetic field inhomogeneities. Advantages and disadvantages of these various solutions are reviewed. In addition, specific applications in imaging experiments for some advanced shimming strategies are discussed, when the conventional shimming solutions are inadequate.
Trong-Kha Truong

10:00
Break & Meet the Teachers

10:30
Coil Design Considerations, Manufacturing & Limitations

Improvements in resolution and speed in recent MRI scanner generations were only possible with the development of high-performant gradient systems. Present gradient technology allows gradient amplitudes of up to 80mT/m and slew rates of up to 200T/m/s simultaneously for conventional whole-body systems. Even higher amplitudes and slew rates are possible using dedicated coils and special gradient systems. In this talk we will describe gradient coil design methods including boundary conditions like available space, stray field, forces and vibration. We show limitations to the usage of the possible technical performance due to physiological conditions and other constraints. Several approaches are discussed how to overcome the different limitations.
Eva Eberlein

11:00
Gradient Drivers: Amplifier Considerations, Power, Tuning & Cooling

Gradient driver high capability is needed in the magnetic resonance imaging (MRI) for better image quality, better resolution and faster imaging. Imaging speed and SNR require increased PSD reproduction fidelity and higher power capability. Higher power has been possible with the change of implementation from linear amplifiers to much lower internal losses switched amplifiers. Switched amplifiers consist on a power stage combining multiple switching semiconductors, commanded with high performance digital control. The digital controller requires precise feedback control, gradient coil model and compensation of nonlinearities. The design has to consider efficiency for operation cost and practical thermal management.
Juan Sabate

11:30
Eddy current calibration, compensation and pre-emphasis; and gradient non linearity: Impact on application

Imperfections in applied gradient fields are manifest as deviation from ideal temporal waveforms and spatial nonlinearity.  Eddy currents induced in conductive surfaces are mitigated to a great extent by pre-emphasis of gradient demand to compensate for known inductive loss thereby yielding near-ideal temporal waveforms.  However, residual eddy currents do impact demanding applications and may still require post-acquisition software correction.  Spatial non uniformity of applied gradient fields induce geometric distortions which are effectively removed via automatic 2D or 3D (un)warping, although there is residual bias in diffusion weighting.  This lecture will focus on practical impact of these effects.
Thomas Chenevert

12:00
Lunch & Meet the Teachers

13:30
RF Transmit: Power Delivery, Decoupling, & Duty Cycle

J. Vaughan

14:00
RF Receivers: Signal Detection Chain, Digitization, System Noise Figures - from MRI Signal to Bits

This presentation provides an overview of the receive chain in an MRI scanner.  Topics to be discussed are preamplifiers, device protection, analog to digital conversion, and high speed data links.  Effort will in particular be placed on looking under the hood of basic ADCs to better understand how their performance limits MRI dynamic range.  Finally we will look at the technology future of wireless MRI and local digital MRI receivers.
Greig Scott

14:30
Controlling the MR Subsystems: Pulse Sequence Control, Waveform Generation & Real-Time Control

J. Andrew Derbyshire

15:00
Multi-Modality Imaging in an MRI Scanner: Simultaneous Imaging & Therapy - Making the Systems Compatible

The use of MRI for treatment guidance is growing. The MRI linac is being developed for guidance of external beam radiotherapy. Linacs and MRI are not easily compatible, solutions will be described. The requirements and challenges of robotics for MRI guided brachytherapy will also be described.
Jan Lagendijk

15:30
Break & Meet the Teachers

16:00
Basic MR Safety, SAR & Power Deposition/Monitoring (Includes Effect of RF Coils & Ultra High Fields)

MR safety is an important topic for all users performing MR procedures on humans. In this presentation we want to limit us on the MR system safety without implants. The potential risk of MRI and the international standard which taking them into account will be presented. Further the topic of testing own RF coils will be discussed. In a last part the additional problems from multi transmit RF coils and their monitoring will be covered.
Roger Luechinger

16:30
Peripheral Nerve Stimulation, Implants & Devices: Safe Use & Considerations for MRI

Two of the main safety problems of MRI is discussed. First one is the safety concerns due to the gradient induced peripheral nerve stimulation. Current commercial MRI scanners have gradients which are capable of inducing electric field ın the body in a level that may cause sensation but fortunately this level is far from the possibility of causing harm. The second one is related to the safety of the patients who wear implantable medical devices. The radiofrequency pulses of MRI may induce currents on its leads. It is feared that this current may reach to a level that it can cause burns.
Ergin Atalar

17:00
Adjournment & Meet the Teachers


Weekend Course

Cardiac MRI: The Basic Principles & Applications

Organizers:Martin Graves Ph.D. & Jeanette Schulz-Menger M.D.

Nicoll 1 8:00 - 12:00 Moderators:Daniel Ennis & Jeanette Schulz-Menger

8:00
Key Clinical Cardiac MRI Concepts: How We Do It

Reza Nezafat

8:20
Key Clinical Cardiac MRI Applications: Where CMR Makes a Difference & Why

CMR has a key role in multiple clinical application where it provides unique and important information.  This talk will discuss the role of CMR in a number of these applications including: evaluation of congenital heart disease, evaluation of cardiomyopathy, understanding the etiology of acute chest pain, the evaluation of cardiac masses, and the evaluation of pericardial disease.  For each application, we will discuss the CMR techniques used and how and why CMR makes a difference.
Michael Salerno

8:40
Systolic Function

This course will provide an understanding of systolic function assessment using MRI that goes beyond left ventricular ejection fraction. We will delve in detail on strain quantification for regional myocardial function assessment. The attendee will be able to definition the meaning of strain and understand how to interpret the different components of strain. Each topic will include acquisition methods, post-processing and analysis methods. We will finally end with examples of a few applications of systolic function assessment from MRI.
Alistair Young

9:10
Diastolic Function

Diastolic dysfunction is a sensitive marker of cardiac disease and an important cause of heart failure. MRI offers a variety of possibilities for the diagnosis of diastolic dysfunction. MRI markers of diastolic dysfunction directly related to structural remodeling are increased left atrial sizes or left ventricular masses. Functional MR parameters of disturbed diastolic function include both altered mitral inflow curves and pulmonary vein flow curves as well as increased E/Ea values assessed by MR phase-contrast imaging. Furthermore, a comprehensive regional analysis of diastolic ventricular motion and deformation is enabled using MR Tagging, Tissue Phase Mapping or MR Feature Tracking. These methods also allow the assessment of single motion/deformation parameters such as untwist or long-axis strain-rate or velocities, as indicators of active relaxation.
Daniela Föll

9:40
Break & Meet the Teachers

10:00
Contrast Enhanced Perfusion At Rest & Stress

Sanjay Agrawal

10:20
Dobutamine Stress Imaging

Sanjay Agrawal

10:40
Challenges & Limitations in Ischemia Imaging

Myocardial perfusion acquisitions have high sensitivity/specificity for the detection of ischemia though are challenged by motion, dark rim artifact, and issues with quantification. These issues are briefly addressed in this syllabus, with references to more of the work done in these areas.
Ed DiBella

11:00
Late Gadolinium Enhancement in Ischemic Heart Disease

Ulrich Kramer

11:20
Late Gadolinium Enhancement in Non-Ischemic Heart Disease

Victor Ferrari

11:40
Challenges & Limitations in Diffuse Fibrosis Imaging

Early detection of diffuse fibrosis in myocardium would offer the hope of treatment for reversing it before irreversible damage becomes evident from other symptoms. Currently there is no established early-stage clinical test for diffuse fibrosis except myocardial biopsy, but MRI may deliver this test. Most cardiac MRI of diffuse fibrosis is based on T1&ECV measurements. The T1 of myocardium and its response to Gad is therefore fundamental in understanding some limitations and is described first. Methods of cardiac T1 mapping are described with some of the issues affecting their accuracy and precision. Potential alternative diffuse fibrosis methods in MRI are mentioned briefly. Clinical research by MRI in diffuse fibrosis is plentiful as group studies, but for early-stage diffuse fibrosis assessment the scatter still defeats it. Here is a challenge with a strong clinical call: improve MRI for individual patient diagnosis or monitoring of early changes in myocardial diffuse fibrosis.
Peter Gatehouse

12:00
Adjournment & Meet the Teachers


Weekend Course

Introduction to Functional MRI

Organizers:James Pekar, Ph.D. & Joshua Shimony, M.D., Ph.D.

Nicoll 2 8:00 - 11:30 Moderators:James Pekar & Joshua Shimony

8:00
The Physiological Basis of the fMRI Signal

While BOLD fMRI represents an invaluable tool to map brain function, it does not measure neural activity directly; rather, it reflects changes in blood oxygenation resulting from the relative balance between cerebral oxygen metabolism (through neural activity) and oxygen supply (through cerebral blood flow and volume). As such, there are cases in which BOLD signals might be dissociated from neural activity, leading to misleading results. The emphasis of this course is to develop a critical perspective for interpreting BOLD results, through a comprehensive consideration of BOLD’s metabolic and vascular underpinnings.
Clarisse Mark

8:30
Data Acquisition Considerations

·              EPI favors high bandwidth acquisitions to reduce susceptibility artifacts.

·              fMRI acquisition methods critically depend on the targeted spatiotemporal resolution.

·              The spatiotemporal resolution of fMRI can be optimized by a combination of k-space trajectory design, receiver coil array, and reconstruction algorithm.

·              Sequences using spin-echo or gradient-echo, the echo time, and the flip angle can tune the sensitivity of fMRI acquisitions.

·              Physiological noise is a dominant noise source in high-field fMRI experiments.

·              Care must be taken to get the best shimming and to minimize motion as well as acoustic noise/vibration.

Fa-Hsuan Lin

9:00
Paradigm Design

A presention on fMRI paradigm design for students and researchers with no or limited experience in setting up BOLD fMRI studies in terms of paradigm (task) design
Jeroen Siero

9:30
Break & Meet the Teachers

10:00
Pre-Processing of fMRI Data

The target audience is researchers and clinicians with limited to no experience with fMRI imaging. As a result of this presentation the audience will know (i) what fMRI pre-processing is, and why it is important, (ii) the basic pre-processing steps and software packages available for implementing them, (iii) how to choose pre-processing steps for different data sets and experimental paradigms, and (iv) about recent developments in automated optimization of pre-processing of fMRI data.
Stephen Strother

10:30
Analyzing Data Using the General Linear Model

The general linear model (GLM) is the most common framework for analyzing task-based fMRI data. In this talk, we motivate its use from the precarious contrast-to-noise situation of fMRI, which requires not only modeling (or fitting) of experimental factors and confounds, but also statistical assessment of their significance in the presence of an irreducible noise floor. The presentation will feature analyses of simulated and measured fMRI data to highlight GLM parameter estimation as well as statistical inference (t-, F-tests) and its representation in Statistical Parametric Maps. Finally, limitations of the GLM and intricacies are discussed, e.g. correlated regressors or multiple comparison correction, to enable its proper use in practice.
Lars Kasper

11:00
Introduction to Resting-State fMRI & Functional Connectivity

In this education workshop, I will motivate the use of resting-state fMRI (rs-fMRI) and functional connectivity to study the human brain. I will also present example studies that use rs-fMRI as a tool to investigate brain organization, disorder and behavior. I will conclude with some existing challenges about rs-fMRI.
Thomas Yeo

11:30
Example Applications of fMRI in Basic & Clinical Neuroscience

Both task-based and resting-state fMRI have been widely used to understand the functional organization of the brain. Both techniques have also been applied in patients for guiding neurosurgery, distinguishing disease phenotypes, supporting clinical management, and evaluating treatment response. Nonetheless, several technical and pathophysiological issues will need to be considered for clinical fMRI.
Kai-Hsiang Chuang

12:00
Adjournment & Meet the Teachers


Weekend Course

Diffusion MRI Light

Organizers:Daniel C. Alexander, Ph.D., Chunlei Liu, Ph.D. & Stephan E. Maier, M.D., Ph.D.

Nicoll 3 8:30 - 12:00 Moderators:Chunlei Liu & Stephan Maier

8:30
Introduction to Diffusion Weighted Imaging

Diffusion MRI is a technique that can probe direction-dependent diffusivity of water molecules to reflect, on a statistical basis, the displacement distribution of the water molecules present within a MRI voxel.  The observation of this displacement distribution may thus provide unique clues to the structure and geometric organization of tissues.  Here, I will review the principle of diffusion MRI and its applications in neuroscience.
Ching-Po Lin

9:00
Diffusion Tensor Imaging & Higher Order Methods

In this lecture, we will explore the non-Gaussian diffusion signal as measured in biological tisues by varying both the gradient wave vector q and the diffusion time t, the time over which the molecules diffuse. The concepts of q-space imaging, diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) will be covered, as well as other higher order diffusion methods. In addition, we will illustrate how varying the diffusion time t provides complimentary information about microstructural length scales. 
Els Fieremans

9:30
Probing Microstructure with Diffusion MRI

Diffusion MRI can be used to non-invasively quantify brain microstructure by using analysis methods and models more accurate than diffusion tensor imaging. Biophysical models of diffusion MRI describe the MR signal as originating from diffusion in distinct tissue components, such as the intra-axonal or extracellular space. Comparment sizes, e.g., the average axon diameter, can be estimated using diffusion MRI, provided that the size is above the resolution limit of the acquisition protocol. Orientation dispersion is essential to include in white matter diffusion models.
Markus Nilsson

10:00
Break & Meet the Teachers

10:15
Diffusion Tractography: Principles & Methods

The audience will learn the basic principles of diffusion tractography and be cautious of the limitations of current methods. In particular, the audience will learn the difference between Diffusion Tensor Imaging (DTI) and High Angular Resolution Diffusion Imaging (HARDI) tracotgraphy, from both a deterministic and probabilistic point of view.
Maxime Descoteaux

10:45
Applying Diffusion MRI in Population Studies

The talk will cover various aspects of processing and analysis of diffusion data, from the perspective of population studies. Specifically it will discuss connectome creation, connectomic analysis, automated tract extraction and biomarker creation. In addition to describing the protocol for cross-sectional studies, we will also discuss the extension of these methods to longitudinal studies.  In addition to the description of methods, application to clinical populations will be presented.
Ragini Verma

11:15
Flip Charts - Meet the Experts

12:00
Adjournment & Meet the Teachers


Weekend Course

Molecular & Metabolic Imaging: Initial Clinical Experience with Molecular Imaging

Organizers:Guanshu Liu, Ph.D. & Mark D. Pagel, Ph.D.

Room 300-302 13:30 - 17:00 Moderators:Guanshu Liu & Jannie Wijnen

13:30
Clinical Experience with Hyperpolarized MRI

Craig Malloy

14:00
Multiparametric "Molecular" MR Imaging

Various contrast mechanisms are available using MRI to emphasize specific molecular and cellular features of tissues that have applications in research and clinical management. These intrinsic mechanisms do not require exogenous agents and can be obtained on the same standard equipment as used for routine imaging.
John Gore

14:30
Metabolic Imaging with Spectroscopy

Combining metabolic imaging methods with spectroscopy methods allows for the appreciation of spatial patterns of physiology and metabolism and the complexities of normal and pathological physiology.  A variety of approaches, including traditional spectroscopy, metabolic mapping, and indirect detection of metabolites, are available.
Bruce Damon

15:00
Break & Meet the Teachers

15:30
Cell Labeling & Tracking

This educational session will describe how MRI can be used to detect cells in preclinical models and clinical scenarios. Contrast agent selection and use will be covered, as will MRI acquisition and data analysis methods.
Erik Shapiro

16:00
MR Molecular Imaging Biomarkers in Pharmaceutical Applications

The rapid shift to targeted and personalized therapies by the pharmaceutical industry has led to increasing need for specific and predictive biomarkers of therapeutic response [1].  Imaging methods including MRI provide many approaches to the use of biomarkers that are importantly non-invasive, translational and spatially resolved. Many MRI based molecular biomarkers have been, and continue to be used by the pharmaceutical industry [2-5], though use and related success has been modest so far.  A number of new MR Molecular Imaging applications many associated with imaging agents [6], highlight new promise for clinical biomarkers that can be used reliably for state of the art molecular targets and therapeutic paradigms currently in discovery and soon to be in clinical trials.  This course presentation will outline the way the pharmaceutical industry integrates, uses and needs biomarkers and how MRI biomarkers and new molecular imaging assays fit this need. Reference to prevalence of MRI biomarkers in pharmaceutical literature and clinical trials will be provided.  A number of the latest and most promising areas for MRI pharmaceutical applications will be described.
Patrick McConville

16:30
Clinical Translation of MR Molecular Imaging

This presentation will discuss  the advantages and clinical applications of MR molecular imaging, the path and challenges for clinical translation, factors affecting the clinical translation, design considerations of clinically translatable MR molecular imaging technology, examples and recent progress of promising MR molecular imaging technologies. 
Zheng-Rong Lu

17:00
Adjourment & Meet the Teachers


Weekend Course

An Update on Body MRI Protocols & Applications: Pelvis MRI

Organizers:Ivan Pedrosa, M.D., Lorenzo Mannelli, M.D., Ph.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Room 331-332 13:30 - 15:00 Moderators:Vikas Gulani

13:30
Uterus: Benign Disease

Tracy Jaffe

14:00
Uterus: Malignant Disease

This presentation will highlight the value of MRI for risk-stratification and appropriate treatment selection in patients with new diagnosis of endometrial and cervical cancer. It will also illustrate the central role of MRI prior to fertility sparing treatments in patients with endometrial and cervical cancer, respectively. At the end of the presentation, the attendees will be able to recognize and report clinically pertinent imaging findings when evaluating patients with new diagnosis of endometrial or cervical cancer. This information is important for the radiologist to serve as an effective consultant to the referring physician.
Yulia Lakhman

14:30
Adnexal Masses

MR imaging of adnexal masses can optimally characterise lesions aiding treatment selection. This talk aims to discuss typical and unusual imaging appearances to guide the radiologist with discussion of imaging algorithms and clinical case discussion.
Helen Addley

15:00
Break & Meet the Teachers


Weekend Course

An Update on Body MRI Protocols & Applications: Genitourinary MRI

Organizers:Ivan Pedrosa, M.D., Lorenzo Mannelli, M.D., Ph.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Room 331-332 15:30 - 16:30 Moderators:Vikas Gulani

15:30
Adrenal & Renal MRI

The role of radiologist and imaging is evolving from traditional role of identifying renal lesion and detecting enhancement, to predicting aggressiveness and biology of the renal tumor as well as providing operative guidance. MR imaging can play a very important role not only as a problem solving tool but also as a ‘first-line’ examination for assessment of renal tumors. Additional information garnered from MRI has a potential to significantly impact management by guiding therapeutic decisions.
Hersh Chandarana

16:00
MR Urography & Bladder CA Staging

Urothelial cancer is the most common malignancy of the urinary tract. Most patients present with hematuria and undergo initial imaging with CT and/or ultrasound for the assessment of potential etiologies of this symptom. A cystoscopy and biopsy are necessary to confirm the diagnosis of bladder cancer. The potential role of MRI is to triage patients to different forms of treatment according to the cancer’s stage.
Hebert Alberto Vargas

16:30
Adjourment & Meet the Teachers


Weekend Course

Neuro 1: Head & Neck

Organizers:Jonathan H. Gillard, M.D., FRCR, MBA & Jennifer A. McNab, Ph.D.

Room 334-336 13:30 - 15:30 Moderators:Priti Balchandani & Jennifer McNab

13:30
Head & Neck: The Surgeon's Perspective

Thomas Loh Kwok Seng

14:00
Head & Neck: The Radiologist's Perspective

Eric Ting

14:30
Head and Neck: MRI of Laryngeal and Hypopharyngeal Cancers

Laryngeal and hypopharyngeal cancers have traditionally been staged using CT. These areas have previously been difficult to assess with MRI, given the small structures and prohibitive imaging times. However, with improvements in both hardware and software, thin slice MR images of these areas can now be performed within a reasonable amount of time, with superior soft tissue resolution compared to CT. This allows identification of important features that affect management decisions and help direct treatment, even in recurrent disease. MRI has now become a powerful tool in the management of these neoplasms. 
Julian Goh

15:00
Discussion

15:30
Break & Meet the Teachers


Weekend Course

Neuro 1: Neonate

Organizers:Jonathan H. Gillard, M.D., FRCR, MBA & Jennifer A. McNab, Ph.D.

Room 334-336 16:00 - 18:00 Moderators:Robert Mckinstry

16:00
Neonate: The Neonatologist's Perspective "Preterm newborns: How imaging contributes to the understanding of the preterm infants neurodevelopmental outcome"

This educational presentation will summarize the imaging tools to study the brain of preterm infants, detect brain injury and predict neurodevelopment outcome
Petra Hüppi

16:30
Neonate: The Physicist's Perspective

Simon Warfield

17:00
Term newborns: How imaging contributes to the understanding of the development of brain injury after birth asphyxia

Term newborns are at risk to develop brain injury. Magnetic resonance imaging has permitted to better understand how brain injury develops despite standard available treatments. The use of magnetic resonance imaging has also given clues of which newborns would benefit from additional treatments, and indications for possible alternative treatments. However, magnetic resonance imaging in these newborns remains challenging, and must imperatively be improved to allow further detection and treatment. This education session will cover the advantages and limitations of magnetic resonance imaging in term newborns.
Pia Wintermark

17:30
Discussion

18:00
Adjournment & Meet the Teachers


Weekend Course

Cardiovascular MRI: Vascular Flow & Angiography

Organizers:Daniel Ennis, Ph.D. & Harald Kramer, M.D.

Nicoll 1 14:00 - 17:30 Moderators:Martin Graves & Harald Kramer

14:00
Contrast & Non-contrast Enhanced Methods - Technical Perspectives

Both contrast enhanced (CE) and non-contrast enhanced (NCE) MRA techniques are introduced. In CE-MRA, developing trends including bolus timing estimation, temporal and spatial resolution improvement, and low dose gadolinium (Gd) MRA are revisited. In NCE-MRA, recent developments, including inflow, flow-dependent, and spin labeling techniques are introduced. Clinical applications of these NCE-MRA techniques are also demonstrated.

Mitsue Miyazaki

14:30
Contrast & Non-contrast Enhanced Methods - Clinical Applications

This presentation will demonstrate the technical and clinical applications of contrast enhanced and non-contrast magnetic resonance angiography (MRA). MRA is routinely used to evaluate the vasculature in a non–invasive fashion. Contrast enhanced MRA can be implemented as a conventional timed flow arrest protocol or as time resolved dynamic imaging.  The technical aspects of both of these approaches will be described in detail. Several different Gadolinium based contrast agents are routinely used for CEMRA including both extracellular and blood pool agents. Methods for optimal utilization of contrast agents for MRA will be described. Because of the risk of NSF with gadolinium use in patients with renal failure, there has been renewed interest in non contrast MRA techniques. Several of these NCMRA approaches will be discussed. Through a series of case presentations, this talk will attempt to illustrate the optimal use of all of these techniques in clinical practice. At the end of this lecture, attendees should understand the basic technical principles for CEMRA and NCMRA and will also be more familiar with the appropriate clinical indications for using these techniques.
James Carr

15:00
Break & Meet the Teachers

15:15
Definition of Terms: Static & Dynamic CE‐MRA & 2D/4D Flow

Over the last decades, many methodological advances have been introduced to expand the capabilities of anatomical and functional MRA beyond the basic MR acquisition principles. These innovations provide new opportunities and challenges. Here we will review several key concepts with a special focus on their terminology, protocol choices available to the clinical and research user, and implications on the resulting images in the context of contrast-enhanced MRA and flow MRI.
Oliver Wieben

15:45
Practical Challenges of MRA & Flow

MRA and phase contrast flow measurements involve the measurement of moving bodies, specifically blood (or in some cases CSF). Motion will produces artifact in MR images. While some of these artifacts are advantageous for the purpose of MRA (TOF) and flow images, unanticipated motion will degrade the quality of the exam. This educational section will discuss the practical considerations and challenges when protocolling MRA and flow measurements.
Alex Barker

16:15
Break & Meet the Teachers

16:30
Clinical Applications of MRA

Winfried Willinek

17:00
Clinical Applications of 2D & 4D Flow

Conventional flow-sensitive magnetic resonance imaging (MRI) using two-dimensional (2D) slice selection, cardiac gating, and phase contrast (PC) velocity encoding in one direction is an excellent quantitative alternative to measure blood flow in different vascular territories.  Recent advances allow for the acquisition of MRI data sets with three-directional velocity encoding over a 3D volume throughout the cardiac cycle in clinically feasible scan times of 20 minutes and less. This presentation will discuss clinical applications of 2D and 4D flow MRI.
Alejandro Roldan-Alzate

17:30
Adjournment & Meet the Teachers


Weekend Course

Advanced fMRI: Techniques & Applications

Organizers:Jay J. Pillai, M.D. & Jonathan R. Polimeni, Ph.D.

Nicoll 2 13:30 - 17:20 Moderators:Jay Pillai & Jonathan Polimeni

13:30
Dynamic Functional Connectivity

Dynamic functional connectivity (dFC) uses region-of-interest or data driven methods to elucidate temporally-varying changes in resting-state brain networks. Challenges are the lack of a gold standard for dFC, the difficulty in discriminating signal from non-neurally generated BOLD fluctuations, and the tradeoffs between temporal resolution of the neural dynamics and the statistical significance of the resulting networks. This talk will describe the methods and pitfalls to be avoided in applying these techniques, as well as results that correlate with independently acquired measures of behavior and psychometrics.
Gary Glover

14:05
Network Analysis

Figure 1. Figure illustrates common graph metrics in connectomics (described in the text). 
Martijn van den Heuvel

14:40
Clinical Applications of Functional Connectivity

Steven Stufflebeam

15:15
Break & Meet the Teachers

15:50
Calibrated BOLD fMRI

Calibrated fMRI techniques are used to extract the oxidative metabolism component from the BOLD signal measured in response to a task. Oxidative metabolism is isolated by first estimating the vascular component of the BOLD response through a calibration manipulation and a biophysical model. Various calibration methods have been proposed using mild hypercapnia, hyperoxia, or a combination of the two. Extensions of these techniques now allow measurement of baseline oxidative metabolism. This course will allow fMRI users to learn about calibrated fMRI and how it can be used to obtain quantitative measures of brain activity and resting metabolism.
Claudine Gauthier

16:25
Multi-Band EPI Applications to fMRI

Multi-band EPI is becoming a standard acquisition scheme for functional MRI. Here we will evaluate how multi-band acceleration benefits fMRI. We will address how accelerating to increase temporal resolution leads to de-aliasing of nuisance physiological signals and supports resolving complex BOLD activity. In accelerating to increase spatial resolution, we will consider temporal signal-to-noise ratio losses due to high resolution, and how multi-band compensates through imaging more volumes. We will assess multi-band multi-echo fMRI, which incorporates T2* relaxometric techniques for susceptibility artifact compensation and thermal noise reduction. Lastly, we will review the multi-band EPI configuration of the Human Connectome Project and clinical translatability of its multi-band approach.
Prantik Kundu

17:00
Adjournment & Meet the Teachers


Weekend Course

Diffusion MRI Applied

Organizers:Daniel C. Alexander, Ph.D., Chunlei Liu, Ph.D. & Stephan E. Maier, M.D., Ph.D.

Nicoll 3 13:30 - 18:00 Moderators:Els Fieremans & Stephan Maier

13:30
Diffusion MRI of Neurodevelopment

Pratik Mukherjee

13:55
Diffusion MRI of Aging & Neurodegeneration

Diffusion MRI can provide not only parametric and but also directional information, which quantify white matter fiber integrity and cellular density as well as neural connectivity between nodes in the brain. In this talk, we will give the audience how to preprocess imaging data, for example, distortion and bias correction. Then, we will show several results for parametric analyses and structural connectivity measured by diffusion MRI in normal aging and neurodegenerative disorders.
Osamu Abe

14:20
Diffusion MRI of Stroke

Stroke is the second leading cause of death world-wide. Diffusion-weighted MRI (DWI) is very sensitive to early acute ischemic injury, with mean diffusivity reduced in the hyperacute stage, but elevated in the chronic stages. In addition, DWI can potentially be combined with other MRI sequences to stage extent of ischemic injury and identify potentially salvageable tissue. Diffusion-tensor MRI and high angular resolution diffusion MRI techniques can be used to evaluate ultrastructural injury post-stroke. DWI has been shown to critical for improving the diagnosis, prognosis and management of acute ischemic stroke patients and for monitoring post-stroke recovery.
Ona Wu

14:45
Diffusion MRI of Psychiatric Disorders

Diffusion MRI has proven to be a very popular brain imaging technique for the study of psychiatric disorders. In schizophrenia alone, there are 570 publications that use diffusion tensor imaging.  Diffusion MRI data has been used in many ways including: assessment of white matter integrity,  tractography and structural connectivity analyses.  Many different analytic approaches have been developed.  Like other MR modalities, diffusion MRI is also subject to artifacts from multiple sources which can result in erroneous values.  Diffusion models, other than the tensor model, are beginning to become popular as fast imaging techniques make them more feasible for clinical populations.
Kelvin Lim

15:10
Diffusion MRI in Forensic Medicine

Educational lecture on Diffusion MR Imaging in forensic medicine and research.
Kathrin Yen

15:35
Break & Meet the Teachers

16:00
Water Diffusion Characteristics of Tumors

Thomas Chenevert

16:25
Diffusion MRI of Brain Tumors

The presentation will provide the diagnostic tips of brain tumors and tumefactive lesions by using DWI and ADC. 
Fumiyuki Yamasaki

16:50
Diffusion MRI of Tumors Outside the Brain

Taro Takahara

17:15
Musculoskeletal Applications of Diffusion MRI

In this educational contribution the use of diffusion-tensor (DT-) MRI muscle fiber tracking for studying muscle architectural properties will be discussed. Topics include the importance of muscle structure to muscle function, how muscle architecture is typically assessed, and DT-MRI and its application to muscle. Examples will be given of how DT-MRI data have been used to provide new insights into muscle function, and lastly, important future research directions will be highlighted. 
Gustav Strijkers

17:40
Adjournment & Meet the Teachers



Sunday, May 8, 2016

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Weekend Course

Clinical Cancer MRI: Case-Based: Guidelines & Reporting Standards

Organizers:Linda Moy, M.D. & Valeria Panebianco, M.D.

Room 300-302 8:15 - 17:15 Moderators:Linda Moy & Valeria Panebianco

8:15
MRI Interpretation of Liver Nodules in Cirrhosis — A Standardized Approach Using LI-RADS

This case-based lecture will briefly review basic LI-RADS concepts and then illustrate the use of LI-RADS to categorize liver observations.
Claude Sirlin

8:45
DWI for diagnosis of breast cancer

There are already several established advantages of using DWI to diagnose breast cancer. Standardization and improvement of technology should be made to expand the clinical application of DWI in the future.
Naoko Mori

9:15
Synopsis of the PI-RADS v2 Guidelines for Multiparametric Prostate Magnetic Resonance Imaging and Recommendations for Use*

This presentation provides a short description of PI-RADS v2. It provides discussion of some of the key differences and improvements comparedwith PI-RADS v1 and is focussed on the assessment criteria for detection and diagnosis of significant PCa on mpMRI examinations and clinical uses and limitations. 
Jelle Barentsz

9:45
Roundtable

10:00
Break & Meet the Teachers


Weekend Course

Clinical Cancer MRI: Case-Based: Addressing Clinical Needs

Organizers:Linda Moy, M.D. & Valeria Panebianco, M.D.

Room 300-302 10:15 - 12:00 Moderators:Linda Moy & Valeria Panebianco

10:15
Overdiagnosis & Over Treatment

Overdiagnosis is an important issue in oncologic radiology.  Avoiding diagnosis of disease altogether in order to avoid overdiagnosis is, however, probably not the best solution to the problem.  Choosing appropriate Treatment based on Imaging as well as proteomic and genomic Information is probably more useful. Moreover, overdiagnosis is not the most important concern of current Screening programs - rather, under-diagnosis is. MRI is probably the best method to avoid both, over- as well as underdiagnosis 
Christiane Kuhl

10:45
Tumour Recurrance & Pseudo-Progression in Glioma

Alberto Bizzi

11:15
Finding Cancer in the Dense Breast: Ultrasound & MRI

Features of undiagnosed breast cancers on prior screening US and screening MRI of patients with breast cancers diagnosed on subsequent screening examinations will be presented.
Nariya Cho

11:45
Roundtable

12:00
Lunch & Meet the Teachers


Weekend Course

Preclinical Imaging

Organizers:Peter Caravan, Ph.D., Guanshu Liu, Ph.D. & Mark D. Pagel, Ph.D.

Room 324-326 8:30 - 16:15 Moderators:Yen-Yu Ian Shih & Kai Zhong

8:30
MR Physics for Preclinical Imaging

Magnetic resonance imaging (MRI) is a powerful and versatile modality for preclinical studies. A particular strength of MRI is the wide variety of different image “contrasts”, many of which do not involve use of external contrast agents, that are available in imaging studies. These contrasts derive from the rich physics associated with the interaction of nuclear spins with external magnetic fields. This talk will provide an introduction to these physical principles. The presentation will be didactic in nature, with an emphasis on principles and insights, rather than equations and mathematics.
Joel Garbow

9:00
Technical Aspects for Performing Small Animal MRI

Among the imaging modalities commonly encountered in small animal imaging, MRI is arguably the most versatile imaging modality because of the rich tissue contrasts it provides. In designing and implementing small animal MRI studies, there are several technical aspects, mainly related to the unique anatomy and physiology of small animals, that need to be considered, including but not limited to: pros and cons of in vivo and ex vivo MRI; imaging resolution and speed; and image contrasts. Instead of providing a one-size-fit-all solution, this course tries to provide a general guide for people interested in this topic.
Jiangyang Zhang

9:30
Technical Aspects for Performing Small Animal MRS & MRSI

Neurochemical profiling of rat or mouse brain by MRS and MRSI requires optimization of many steps. Despite a strong magnetic field and the latest RF coil technology available, the spectral quality obtained might not be as expected. This presentation will give an overview of other factors that could be considered to achieve a consistent high quality spectroscopic dataset. 
René in 't Zandt

10:00
Break & Meet the Teachers

10:30
Advantages & Disadvantages of Low Field MRI for Animal Molecular Imaging

MRI imaging provides very high spatial resolution and is very adept at morphological imaging and functional imaging (Molecular imaging, 2016). MRI imaging is non-invasive, making it possible for repetitive observations. Field strength is an important factor in selecting an MRI system for Animal Molecular imaging. The purpose of this talk is to explicate the important role of MRI for animal molecular imaging, the characterization of MRI imaging field strength, advantages and disadvantages of low field MRI for animal molecular imaging, the types of magnet technologies for low field preclinical MRI, and the strength and weakness of MRI systems using different magnet technologies. An understanding of both the advantages and disadvantages of different field strength choices and different magnet technologies is beneficial in determining a threshold of performance where going higher in field strength yields diminishing results for animal molecular imaging. Going through this exercise and determining that threshold will result in an optimum choice of MRI field strength for animal molecular imaging. Although High Field MRI (above 4.7T) has advantages for neurobiology applications, Low Field MRI for animal molecular imaging (1.5T to 4.7T) can provide more than adequate performance for most applications and can offer the benefits of lower cost, significantly easier siting, and remarkably low maintenance. 
Vera Zhang

11:00
Maintaining Animal Physiology

MRI of small rodents requires a longer data acquisition than human subjects due to the small anatomic structures requiring high image resolution with high SNR. Thus, maintenance of animal physiology throughout the study plays a crucial role in a successful small animal MRI study. Among all physiological parameters, core temperature and physiological respiration is the most critically important. Avoiding non-physiological respiration due to hypothermia and inappropriate physical restraints will reduce animal stress and mortality. Examples of how this can be achieved in a typical small animal scanner will be described.
Sheng-Kwei Song

11:30
Data Processing

Experimental magnetic resonance imaging is a powerful tool in biomedical research that can provide unique insight into the structure, function, and composition of tissue in vivo.  MRI data and associated analyses range in complexity and may be comprised of multiple sets of software tools and processes.   In this lecture, we will survey common approaches to processing MRI data, and tools and practices that facilitate the integration and use of experimental MRI in routine biomedical research.
James Bankson

12:00
Lunch & Meet the Teachers

13:30
Ex vivo MRI – Beyond Rodents

Over the past few decades, the use of ex vivo MRI has become widespread. This phenomenon was largely driven by the early development of various mammalian ‘brain atlases’ for neuroscientific applications as well as the need to characterize metabolism and other pathways in cells, isolated organs and cancer models. These early studies set the stage for more unconventional applications of ex vivo MRI. Recent advances in MRI hardware, RF coil design, pulse sequence design, image processing and visualization software, the availability of complementary modalities such as optical and micro-CT imaging, and affordable computational power have driven a slew of new applications of ex vivo MRI.  Therefore, recent applications of ex vivo MRI that are ‘off the beaten path’, or ‘beyond rodents’ are the focus of this lecture.
Arvind Pathak

14:00
MRI of Standard Large Animals

Large animal models are frequently used to develop new MRI pulse sequences, devices, or drug therapies.  In addition, MRI and MRS studies in large animals can aid with the mechanistic understanding of many diseases.  Recently, the use of spontaneous disease models in pets has been gaining traction for rapid translation from bench to bedside.  Tricks and tips for both MRI in both  traditional laboratory large animal and pets will be discussed.
Dara Kraitchman

14:30
Break & Meet the Teachers

14:45
Exciting and Relaxing Fish

Exciting and relaxing fish. A detailed session on the methods and pitfalls of MRI of fish. The session covers, preparation, imaging and post-processing of fish MRI.
Andrew Janke

15:15
MRI of Unusual Animals

Preclinical research relies heavily on the use of traditional research animals which are well-characterized and share our mammalian ancestry. However, in some cases there exist untraditional research animals that are more suited to study specific preclinical questions. This is formulated in the August Krogh Principle: “For a large number of problems there will be some animal of choice or a few such animals on which it can be most conveniently studied”. This applies to a number of MRI experiments in which the use of unusual animal models is justified because of certain capabilities that cannot be mimicked in traditional models.
Henrik Lauridsen

15:45
Adjourment & Meet the Teachers


Weekend Course

Challenges in Imaging the Musculoskeletal System After Treatment

Organizers:Jenny T. Bencardino, M.D., Eric Y. Chang, M.D., Christine Chung, M.D., Philip Robinson, M.D. & Siegfried Trattnig, M.D.

Room 331-332 8:00 - 15:30 Moderators:Laura Bancroft & Jenny Bencardino

8:00
MR Imaging After Rotator Cuff Repair

Radiologists should understand and pay great degree of attention on the technical aspects of the operation, such as anchor types, suture patterns, suture materials, and instruments as well as expected and abnormal MR findings when read the post-operative MRI after rotator cuff repair surgery.
Young Cheol Yoon

8:30
Imaging Following Shoulder Instability Surgery

Imaging following shoulder instability surgery depends on suspected pathology. Direct anatomic repair of labral tears may be perfomed in conjunction with capsular shift. There should be no separation of the labrocapsular complex and glenoid margin with intact labral repair. Overall accuracy of MR arthrography for detecting labral tears after prior instability repair is > 90%.  Arthroscopic Bankart repair may be performed in conjunction with remplissage procedure in patients with engaging Hill-Sachs lesion. MRI will show reattachment of posterior structures into the defect, along with anchor embedded in the trough. Postoperative imaging of Laterjet procedure must assess incorporation of the bone block and any recurrent imaging features of instability.
Laura Bancroft, MD

9:00
MRI of the Postoperative Elbow

Hollis Potter, MD

9:30
Post Treatment Wrist

Shadpour Demehri

10:00
Break & Meet the Teachers

10:30
Imaging Following Cartilage Repair

Michael Recht

11:00
Postoperative Hip: FAI & Dysplasia

dGEMRIC is a biochemical imaging technique that can assess the charge density of cartilage.  Cartilage can respond to increased mechanical loading by increasing charge density.  In acetabular dysplasia, there is increased mechanical load due to the shallow acetabulum, which will normalize after pelvic osteotomy.  Prospective monitoring of the hip cartilage before and after osteotomy using dGEMRIC demonstrates that cartilage responds appropriately to alterations in hip mechanics after osteotomy for dysplastic hips.
Young-Jo Kim

11:30
Entrapment Neuropathies of the Pelvis Following Surgery

Entrapment neuropathies of the pelvis following surgery are rare but important causes for a negative outcome or complications after surgery.
Gustav Andreisek

12:00
Lunch & Meet the Teachers

13:30
Postoperative Ankle

James Linklater

14:00
Postoperative Knee: Menisci

In this lecture, the meniscal anatomy and the important role the meniscus plays in the structure and function of the knee will reviewed, followed by a discussion of the three surgical strategies for operative treatment of meniscal tears (resection, repair, and replacement). MR protocol choices for postoperative assessment of the meniscus will be presented as well as normal and abnormal MR imaging findings in the postoperative meniscus after each of the different surgical procedures.
Edwin Oei

14:30
Postoperative Knee: Ligaments

James Griffith

15:00
Postoperative Knee: Total Knee Replacement

The purpose of this presentation is to provide an overview of the possibilities and restrictions of todays MARS MR imaging techniques in patients after total knee replacement. After following this presentation, the learners will understand the major clinical problems faced by orthopedists after total knee replacement, how MR imaging can contribute in these situations and where the limitations of today’s technical possibilities are in a clinical setting.

Florian Buck

15:30
Adjournment & Meet the Teachers


Weekend Course

Neuro 2: Spine & Plexus

Organizers: Toshiaki Taoka, M.D., Ph.D. & Kelvin Lim, MD

Room 334-336 7:30 - 9:30 Moderators:Alex MacKay

7:30
Advanced Mutimodal Imaging of the Spine

The role of diffusion weighted imaging has expanded beyond the brain to whole body applications.  This presentation will explore the contribution of DWI in the routine evaluation of spinal conditions focusing on its role in the detection, characterization and surveillance of neoplastic, degenerative and infectious diseases.  MR spectroscopy has the power to delineate the chemical signature of tissues in health and disease.  Research suggests detection of key MRS biomarkers may have a role analogous to provocative discography in identification of the painful disc.  This presentation will cover the key findings in the painful disc and review the research work done to date.
Lawrence Tanenbaum

8:00
Plexopathy

Review of the anatomy of the brachial plexus and lumbosacral plexus and the pathologies resulting in plexopathy and their imaging characteristics.
Cynthia Chin

8:30
New Imaging Techniques for Spine & Plexus

While multi-parametric MRI (mpMRI, which includes functional MRI, diffusion tensor imaging, etc.) has become popular for brain imaging, it is still difficult to apply these techniques to the spine because of complex issues related to acquisition and processing of the data. In this review we will examine several key aspects of mpMRI in the spine, namely: hardware, pulse sequences and image processing techniques – discussing their present status, unresolved issues, and future directions. 
Julien Cohen-Adad

9:00
Discussion

9:30
Break & Meet the Teachers


Weekend Course

Neuro 2: Pediatric

Organizers:Kelvin Lim, M.D. & Toshiaki Taoka, M.D., Ph.D.

Room 334-336 10:00 - 12:00 Moderators:Suchandrima Banerjee

10:00
Malformations of Cortical Development

This lecture presents an update on the genetics, signaling pathways and abnormal microstructure that lead to malformations of cortical development.  The organization of this talk is one framework for moving beyond description of the phenotype to a mechanistic understanding of cortical malformations.
Robert McKinstry

10:30
Pediatric: Tumours

Pediatric brain tumors are a leading cause of cancer-related death in children. In recent years, new technologies of molecular and genetic analysis of pediatric brain tumors have provided abundance of biological information. This has resulted in refining tumor classification into subgroups with potential clinical implications and treatment. This lecture demonstrates imaging findings and pathology of pediatric brain tumors and associated genetic syndromes, and an overview of recent developments in molecular biology and genetics. This knowledge is important for the diagnosis, management and future treatment of pediatric brain tumors as well as guiding future research.
Toshio Moritani

11:00
Perinatal Brain Injury & Mimics

P. Ellen Grant

11:30
Discussion

12:00
Lunch & Meet the Teachers


Weekend Course

RF Engineering: Coils

Organizers:Nicola F. De Zanche, Ph.D. & Graham C. Wiggins, D.Phil.

Summit 1 8:30 - 16:45 Moderators:John Andrew Derbyshire & Graham Wiggins

8:30
Basics of Transmission Lines & Power Transfer

Fundamentals of transmission lines and power transfer are presented to help in the understanding, design, implementation and performance evaluation of MRI hardware.
Natalia Gudino

9:00
Volume & Surface Coils

Highlights: RF coils are an essential part of a MRI system to excite and receive MR signals. Their performance is very important for the quality of MR imaging.

· Volume coils provide relatively uniform sensitivity over a large volume.

· Surface coils are designed to maximize SNR and enable parallel imaging

· Volume coils and surface coils usually work together in the RF system to optimize the RF excitation and reception performances at the same time

· Decoupling technologies are needed in the design to minimize coupling between transmit and receive coil elements

Bei Zhang

9:30
Multi-Tuned Coils

Dual-tuned coils provide metabolic information (x-nuclei module) and co-registered anatomical images and B0 shim settings (1H module) and 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.
Ryan Brown

10:00
Break & Meet the Teachers

10:30
Receive Arrays & Circuitry

Boris Keil

11:00
Transmit Arrays & Circuitry

Transmit arrays enable finer RF driving over the RF field distribution in exciting the MR signals.

In this session the following issues will be introduced.

- Transmit Arrays

- Decoupling and Matching/Tuning Techniques for Multi-element coil

- Individually Driven Coil Element

- SAR and Tissue Heating

Yeun Chul Ryu

11:30
RF Modelling

RF modelling is now routinely performed in the design and analysis of MRI RF systems. This talk shares insights into technical details of implementing the most popular numerical electromagnetic (EM) methods. In particular, hybrid full-wave EM methods and parallel computing are highlighted, which creates a powerful theoretical prototyping platform for the design of novel RF coil systems. It is hoped that this talk can aid those who intend to implement demanding computational experiments for the research and development of RF coil designs for high-field MRI applications.  
Feng Liu

12:00
Lunch & Meet the Teachers

14:00
Dielectric Materials & Resonators

This session explains the source of dielectric effects in MRI. It is furthermore explained how the dielectric effects can be used to improve image and spectra quality.
Sebastian Aussenhofer

14:30
Dipoles & Traveling Waves

NMR and MRI signal detection is traditionally based on Faraday induction. The local magnetic moment produced by the nuclear spins is thereby excited and detected by near-field magnetic interaction with the coil. However, the basic physical regime governing the electrodynamics of the RF detector alters at ultra-high frequencies and therefore the instruments applied in these systems have to cope with a different situation than at lower field strengths. The emergence of field propagation phenomena and radiation allows and necessitates the application of new RF topologies that are not only targeted at producing and detecting magnetic fields in their reactive near field.
David Brunner

15:00
Break & Meet the Teachers

15:30
Construction of Rx Arrays

In this live demonstration of RF coil construction, we will first present general RF-coil construction methods and some useful accessories and tools built in our lab. We will then guide the audience through all main design and construction steps while building a simple (but rather unconventional) Rx array. We will show some alternative decoupling techniques (not relying on preamplifier decoupling) to compensate mutual inductance and minimise coil-coil coupling. The presented methods will be easily applicable to construct other simple RF coil arrays, including Tx/Rx arrays. Finally, we will present some imaging results on a human wrist using this array.
Ewald Weber

16:15
Adjournment & Meet the Teachers


Weekend Course

Image Acquisition & Reconstruction

Organizers:Thomas K. F. Foo, Ph.D. & N. Jon Shah, Ph.D.

Summit 2 8:30 - 17:00 Moderators:Desmond Teck Beng Yeo

8:30
RF Pulse Design

Excitation is a necessary process for MRI in order to create observable magnetization to image.  In this work, we develop the basic principles of excitation using the Bloch Equations, written for the rotating frame, which makes it easier to visualize the effects of applied rotating magnetic field used for excitation.  The small tip angle approximation is shown to be useful for understanding slice profile and multidimensional excitation.  Large tip-angles requires different approaches, such as the Shinnar-LeRoux algorithm. Lastly, excitation k-space, similar to k-space for image acquisition, is a concept that can be used to design complicated patterns of excitation.
Douglas Noll

9:00
Systems Calibrations (Bo, B1, Flip Angle Mapping, Shimming)

Lawrence Wald

9:30
Prescan: Transmit/Receive Gain Settings, Frequency Calibration

RF transmit/receive gain and transmit/receive frequency must be adjusted for each patient exam. The problem is similar to parameter mapping but over a smaller volume.  Transmit gain accuracy ideally produces the desired flip angle, however B1 field non-uniformity prevents this in practice. The receive gain is ideally set so that the maximum signal does not saturate the A/D converters which would produce shading, and the noise standard deviation is at least one bit to avoid quantization error.  Transmit/receive frequency accuracy is required for accurate localization, good EPI and spiral image quality and for fat suppression pulses to work optimally.
Kevin King

10:00
Break & Meet the Teachers

10:30
Motion Compensation Methods

MRI’s relatively long scan times can result in increased vulnerability to motion artifacts, producing degraded image quality, more complex patient workflow, and the need in some cases for patient sedation, restraint, or rescanning. Most commercial scanners employ a range of methods to ameliorate motion problems, including gating, triggering, and respiratory navigation techniques. In addition, a number of new technologies are under investigation. These include advanced two and three dimensional navigator methods, and self-navigation techniques, which correct for motion using the imaging data themselves, without the need for separate motion-tracking sequences. 
Christopher Hardy

11:00
External Sensors & Real-Time Compensation

This talk will provide an overview on current methods in prospective motion correction for head MRI. It includes both optical motion correction methods as well as NMR-based methods. A selection of currently available technologies will be discussed, including moiré phase tracking, self-encoded optical markers, and gradient tones.
Maximilian Haeberlin

11:30
Non-Cartesian Methods (Radial, Spiral) & Considerations

Xiaohong Zhou

12:00
Lunch & Meet the Teachers

13:30
Reconstruction of Non-Cartesian k-Space Data

The most common reconstruction strategy for non-Cartesian data is to interpolate the data onto a Cartesian k-space grid, followed by a Fast Fourier Transform to the image domain. However, interpolation has important consequences for the final image, so it must be properly chosen and compensated, though several packages yield good results using standard parameters. In addition, iterative techniques, both with and without regridding, can be used to incorporate an enormous range of imaging strategies.
Gigi Galiana

14:00
Parallel Imaging & Multi-Coil Image Reconstruction

Parallel imaging reconstructions using multiple receiver coil data will be discussed, with a focus on Cartesian parallel imaging methods. SENSE and GRAPPA will be used as the representative techniques that are both widely used, and help understand a variety of other technologies.
Vikas Gulani

14:30
Compressed Sensing Reconstruction

Many methods have been proposed to address the spatio-temporal resolution tradeoff in MRI. Compressed sensing (CS) is the latest among these and holds great promise. This talk covers the basics of compressed sensing reconstruction and also touches on more advanced CS methods that incorporate parallel imaging and redundant coil information.

Manojkumar Saranathan

15:00
Break & Meet the Teachers

15:30
MR Fingerprinting

Mark Griswold

16:00
Synthetic MRI

Synthetic MRI has been a long-standing dream in MRI, which recently gained more attention. Quantification techniques improve and access to clinical application becomes more facilitated. This lecture will explain the technique of synthetic MRI, its limitations and clinical impact.
Marcel Warntjes

16:30
Using MR Phase: Temperature Mapping & Phase-Sensitive Reconstruction

Nathan McDannold

17:00
Adjournment & Meet the Teachers


Weekend Course

Pediatric & Neonatal MRI

Organizers:Neal K. Bangerter, Ph.D. & Michael S. Hansen, Ph.D.

Nicoll 1 9:00 - 12:00 Moderators:Shreyas Vasanawala

9:00
Logistics of Imaging Children

what happens to old when I type new

 

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Kendall O'Brien

9:30
Technologies for Pediatric Neuroimaging

This educational session will introduce technologies for brain imaging of pediatric subjects.  A brief overview of key differences between the developing brain and adult brain will be discussed.  The presentation will be focused on the variety of neuroimaging sequences, anatomical and functional, and post-processing techniques for improved characterization of the maturing brain.  Translational studies will also be presented to highlight the importance of advancing pediatric brain imaging not only in research but also in clinical care, and further identify the area of needs to spur interests from the audience.
Duan Xu

10:00
Coils & Acceleration

Michael Lustig

10:30
Break & Meet the Teachers

11:00
Pediatric Imaging

MRI is an outstanding modality for pediatric body imaging, and offers the prime advantage of lack of ionizing radiation.  However, it is often under-utilized due to challenges with patient cooperation and reliable image quality.  Many of these issues stem from motion artifacts and bloated protocols.  This presentation will cover common imaging indications in the extremities, pelvis, abdomen, and chest, providing streamlined protocols for each.    Several methods for rapid musculoskeletal imaging will be reviewed.  These include targeted protocols and higher-dimensional acquisitions.  An approach to abdominal and pelvic MRI will be presented that uses only a couple of sequences to obtain T2-weighted and post-contrast T1 weighted scans.  Tradeoffs between various methods of T2 weighted imaging will be reviewed.  Further, for MRA and MR venography of the torso, streamlined protocols will be presented that are well-suited to sedated children.  Contrast-enhanced imaging techniques that minimize motion will be presented.
Shreyas Vasanawala

11:30
Cardiac

Paediatric cardiac disease is often complex, requiring comprehensive anatomical and hemodynamic assessment. C Paediatric cardiac disease is often complex, requiring comprehensive anatomical and hemodynamic assessment. Cardiac MRI offers a reference standard method of assessing the cardiovascular system. However, conventional cardiac MRI can be difficult to perform on children due to poor patient compliance. Therefore, accelerated real-time imaging techniques are increasingly used. These will be discussed with particular reference to studies that have demonstrated proven benefit in the pediatric population.   
Vivek Muthurangu

12:00
Adjournment & Meet the Teachers


Weekend Course

Magnetic Susceptibility Imaging

Organizers:Chunlei Liu, Ph.D. & Peter van Zijl, Ph.D.

Nicoll 2 7:55 - 12:00 Moderators:Chunlei Liu & Peter van Zijl

7:55
Susceptibility Properties of Tissue

To review some basic material on magnetic susceptibility in materials and biological tissues
Jürgen Reichenbach

8:20
Susceptibility Weighted Imaging (SWI)

Susceptibility Weighted Images are produced by multiplying T2*-weighted gradient-echo magnitude and filtered phase images to give a distinctive tissue contrast that highlights tissue magnetic susceptibility variations including those due to haemorrhages, iron deposition and calcifications. SWI has become a widespread clinical tool, particularly for vascular pathologies and neuroimaging with musculoskeletal, cancer and other applications emerging. SWI is qualitative, suffering from the orientation-dependent and non-local nature of phase contrast and cannot help to distinguish between positive and negative susceptibilities. Quantitative Susceptibility Mapping (QSM) overcomes these disadvantages and can even be combined with magnitude images to give a single susceptibility-sensitive image.
Karin Shmueli

8:45
Quantitative Susceptibility Mapping (QSM) Basics

Quantitative susceptibility mapping allows the generation of three-dimensional maps showing the variation of the relative magnetic susceptibility within the human body. A number of processing steps are needed to produce susceptibility maps: to convert the wrapped phase measurements into a map of the field variation inside the region of interest; to separate the field perturbation generated by tissue in the region of interest from that produced by external sources; to calculate the susceptibility map from the field perturbation.  Each step will be described here, along with a brief discussion of the relationship between susceptibility and magnetic field perturbation.
Richard Bowtell

9:10
Break & Meet the Teachers

9:20
Translation of QSM to the Clinic - Fast Single Orientation Methods

In this lecture, we will take a look at recent progress toward fast data acquisition and susceptibility map reconstruction that will ultimately set the foundation for a successful translation of QSM to the clinic.
Ferdinand Schweser

9:45
Iron & Susceptibility in Young & Old Brains

The brain is a unique organ with respect to its non-uniformity of iron distribution, both regionally and cellularly, and because of its iron accumulation pattern across the life span. MRI allows to non-invasively map the iron content and therefore provides a window into age and disease dependent mechanisms that are poorly understood. This presentation will give an overview on the most relevant iron compounds in the brain, their magnetic properties, and their cellular distribution. Additionally, susceptibility related MRI methods for iron mapping will be presented and their limitations will be discussed.
Stefan Ropele

10:10
Tissue Anisotropy Origin (Brain, Heart, Muscle)

In this educational presentation, the origins of magnetic susceptibility induced signal anisotropy will be discussed. The observations of magnitude and phase signal anisotropy in gradient echo have been reported in the brain, heart, muscle and kidney. I will explain the sources (e.g. microstructural anisotropy and susceptibility anisotropy) for the observed signal anisotropy. Potential applications of the signal anisotropy will be discussed.
Jongho Lee

10:35
Break & Meet the Teachers

10:45
Tissue Anisotropy Mapping

Many recent studies have found out that macroscopic magnetic susceptibility at the scale of a MR imaging voxel is anisotropic in tissues with ordered microstructure such as white matter fibers. This lecture reviews some of such experimental evidences and introduces methods to map such tissue anisotropy. First, we go over the theory, acquisition and processing methods of susceptibility tensor imaging (STI) which uses MR phase measurements collected at different sample orientations with respect to the main field. We then review some other mapping methods using susceptibility related MR measures that are orientation dependent such as R2* and frequency difference.
Xu Li

11:10
Susceptibility MRI Outside the Brain

There is growing research interest in the development of QSM techniques for extra-cranial applications. These techniques are faced with additional challenges beyond those typically encountered in brain QSM. By addressing important challenges such as the presence of motion, fat, and large susceptibility shifts, these techniques may enable novel QSM applications for research and clinical applications in multiple organs, including heart, liver, kidney, pancreas, breast as well as whole-body applications. 
Diego Hernando

11:35
Pediatric QSM

Deqiang Qiu

12:00
Adjournment & Meet the Teachers


Weekend Course

The Basics of Perfusion & Permeability Imaging

Organizers:Linda Knutsson, Ph.D. & Steven Sourbron, Ph.D.

Nicoll 3 8:00 - 12:00 Moderators:Ganesh Adluru & Andre Ahlgren

8:00
The Physiology of Perfusion & Permeability

This talk provides an overview of several different parameters that are associated with microvascular physiology, such as perfusion, transit time, and capillary permeability.  Their biological meaning is explored, as well as their relevance in the context of various disease settings. Finally, the three main MRI techniques for measuring microvascular physiology (DCE-MRI, DSC-MRI, and ASL) are briefly introduced in relation to the parameters they are capable of measuring.
Hai-Ling Cheng

8:35
Tracer-Kinetic Analysis

This lecture explains the basic principles in tracer-kinetic analysis, assumptions underlying tracer-kinetic analysis models, and limitations and issues in the implementation of these models for perfusion and permeability measurements.
Dennis Cheong

9:10
Break & Meet the Teachers

9:20
Contrast Agent Methods - Data Acquisition

The goal of this lecture is to describe optimal DSC- and DCE-MRI data acquisition techniques and how pulse sequences can be designed to leverage the underlying contrast mechanisms in order to assess unique and complementary biological features.  
Chad Quarles

9:55
Contrast Agent Methods - Post-Processing

This presentation will cover key steps involved in processing dynamic contrast-enhanced MRI (DCE-MRI) and dynamic susceptibility contrast MRI (DSC-MRI) data to extract useful information. In addition to key methods for understanding the time course signals, methods for reducing the impact of motion and artefacts will be considered. Examples will be given in a range of organs and diseases.
Geoff Parker

10:30
Break & Meet the Teachers

10:40
ASL - Data Acquisition

In this talk, we will discuss the following aspects regarding ASL – Data acquisition.

A.     Basic principles

B.     Labeling schemes

        1.     Pulsed ASL

                a)     STAR and variants

                b)     FAIR and variants

        2.     Continuous ASL

        3.     Velocity selective ASL

C.    Background suppression

D.    Readout options

E.     Advanced methods to combine ASL with other measurements

Jun Hua

11:15
ASL- Post-Processing

This educational talk will review the current status of ASL post processing methods.  Based on reasonable assumptions, established ASL post-processing methods enable robust quantitative perfusion maps. Extensions of these post-processing methods address potential issues with ASL and enable new capabilities, including dynamic ASL.  
Craig Meyer

11:50
Adjournment & Meet the Teachers


Weekend Course

Clinical Cancer MRI: Case-Based: Tumour Microenvironment

Organizers:Linda Moy, M.D. & Valeria Panebianco, M.D.

Room 300-302 13:30 - 15:15 Moderators:Utaroh Motosugi & Harriet Thoeny

13:30
Tumour Microenvironment

Historically, radiology/imaging has served to identify tumors in terms of location, size, and metastatic spread. It is increasingly recognized that tumors may exhibit very different micro environmental characteristics, which can influence therapeutic success. A new goal is precision oncology, whereby individual tumors are further characterized based on potential prognostic imagine biomarkers. Tumor hypoxia is associated with aggressive phenotypes and resistance to therapy and may be the most significant factor influencing therapy outcomes for solid tumors. Many NMR approaches are being developed and evaluated to measure tumor oxygenation. This review will consider human applications of oxygen sensitive MRI in the context of pre-clinical developments. Strengths and weaknesses in terms of temporal and spatial resolution, precision and accuracy, ease of implementation and robustness of observations will be considered. Methods may provide qualitative or quantitative insights including dynamic response to interventions.
Ralph Mason

14:00
Collagen & Stroma

The tumor stroma, and in particular the Col1 fiber meshwork, plays an important role in cancer migration and metastasis. Novel MRI approaches such as macromolecular contrast agent based DCE MRI and DTI can be applied to noninvasively detect critical features of the Col1 fiber network in tumors.
Kristine Glunde

14:30
Tumor Associated Inflammation: Biology & Imaging

Heike Daldrup-Link

15:00
Roundtable

15:15
Break & Meet the Teachers


Weekend Course

Clinical Cancer MRI: Case-Based: New Horizons

Organizers:Linda Moy, M.D. & Valeria Panebianco, M.D.

Room 300-302 15:30 - 17:15 Moderators:Utaroh Motosugi & Harriet Thoeny

15:30
A semi-quantitative overview of tumor CEST MRI

Tumor CEST MRI has emerged as a molecular imaging approach to characterize complex microenvironment, including protein/peptide, glutamate, exogenous glucose and artificial reporter gene MRI. Despite their diverse names, variant CEST imaging methods provide complementary information about the underlying tumor pathophysiology and it is helpful to provide a semi-quantitative overview to understand their potential clinical applications.
Phillip Zhe Sun

16:00
Radiomics the New Buzzword

“Radiomics” refers to the extraction and analysis of large amounts of advanced quantitative imaging features from medical images using high throughput methods. In this syllabus MRI radiomics features and extraction are described; second, examples of applications of radiomics in glioblastoma multiforme (GBM) and prostate cancer are reviewed and lastly the importance of incorporating radiomics features in clinical databases is discussed. 
Radka Stoyanova

16:30
Interventional MRI of Cancer

Carlo Catalano

17:00
Roundtable

17:15
Adjournment & Meet the Teachers


Weekend Course

Neuro 2: CNS Infections

Organizers:Kelvin Lim, M.D. & Toshiaki Taoka, M.D., Ph.D.

Room 334-336 13:30 - 15:30 Moderators:Toshiaki Taoka

13:30
CNS Infections: Tropical

In today’s highly connected world, radiologists should be familiar with typical MRI findings of CNS manifestations of common tropical diseases, as well as the limitations of neuroimaging in differential diagnosis. Multi-disciplinary consultations between radiologists, neurologist, infectious disease specialists and neurosurgeons are often helpful to refine the clinical diagnosis and plan a rational approach to management. Newer techniques, including MR spectroscopic and perfusion imaging, may also be helpful for differential diagnosis.  This presentation will focus on differential diagnosis in schistosomiasis and neurocysticercosis, and outbreaks of Nipah virus, group B streptococcus agalactiae infection.
CC Tchoyoson Lim

14:00
CNS Infections: Bacterial/Fungal

Seung Hong Choi

14:30
CNS Infections: Viral

Viruses that tend to affect the central nervous system are usually neurotropic. The specific diagnosis of viral encephalitis requires PCR, serum biomarkers, or culture which are not available at acute setting, while clinical and laboratory findings are often non-specific. MR Imaging study is important in confirming the CNS involvement. Imaging lesion detection can prompt early antiviral treatment until proven otherwise. Imaging approaches to viral CNS infection require background knowledge of the patients, such as ages, host immunity, clinical presentations, geographic considerations and endemics. This lecture will review the basic concepts of MR imaging approaches to common neurotropic viral encephalitis.
 
Cheng-Yu Chen

15:00
Discussion

15:30
Break & Meet the Teachers


Weekend Course

Neuro 2: Psychiatric Disease

Organizers:Kelvin Lim, M.D. & Toshiaki Taoka, M.D., Ph.D.

Room 334-336 16:00 - 18:00 Moderators:Kelvin Lim

16:00
Biological Origin of Depression: Evidence from Infant Brain Imaging and Genetics

Qiu Anqi

16:40
Psychiatric Disease: Post-Traumatic Stress Disorder

This lecture will provide a brief review on the Post-Traumatic Stress Disorder (PTSD) in general,and an overview of the PTSD related brain abnormalities discovered with the use of psychiatric MR, with particular emphasis on the circuitry impairment as observed from the circuit- and network-based analysis. Methodological challenges and opportunities will be discussed, along with the assessment of the clinical usefulness of the research findings using psychiatric MR imaging into the objective diagnosis, prognostic prediction and treatment evaluation of patients with PTSD.
Qiyong Gong

17:20
Discussion

18:00
Adjournment & Meet the Teachers


Weekend Course

Advanced MR Spectroscopy in Operation

Organizers:Anke Henning, Ph.D. & Carolyn E. Mountford, D.Phil.(Oxon)

Nicoll 1 13:30 - 17:40 Moderators:Anke Henning & Carolyn Mountford

13:30
Basic Principles & Sequences for Whole Organ MRSI - Brain & Body

In this course, the basics of maximizing SNR while minimizing sensitivity to system imperfections in MRSI of the human body are discussed using example applications in brain, prostate, breast, and body tuned for the nucleus of 1H, 31P and 19F.
Dennis Klomp

13:50
Whole Brain (Organ) MRSI Analysis

The efficient and accurate analysis of whole brain MR spectroscopic imaging (MRSI) data is critical for the acceptance of this technique into both research and clinical usage. This presentation will review methods for the processing of MRSI data collected with extended brain coverage and high spatial resolution, quantitive analysis methods, creation of metabolic images, and recognition/removal of unwanted artifacts.
Peter Barker

14:10
Applications of Whole Organ MRSI - Brain & Body

MR spectroscopic imaging (MRSI) makes it possible to study changes in metabolism that are associated with disease progression and response to therapy. Advances in MR hardware and software have provided new opportunities for obtaining data in a clinical feasible time and have therefore opened the door to a much broader range of applications than was previously considered. These applications will be demonstrated and future opportunities described.
Sarah Nelson

14:30
Break & Meet the Teachers

14:50
Basic Principles & Sequences for 2D MRS

In one-dimensional (1D) MR Spectroscopy (MRS), it is difficult to resolve the multitude of metabolite peaks that exist over a small spectral range. Spectral-editing techniques target a particular J-coupled metabolite selectively, such as lactate, GABA, glutamate, etc. with a drawback that only one metabolite is selected for each recording. Due to the added 2nd dimension, two-dimensional (2D) MRS can unambiguously resolve many overlapping peaks non-selectively. Instead of a standard 1D spectrum plotting intensity versus a single-axis (i.e., chemical shift + J-coupling), 2D MRS techniques produce a 2D spectrum plotting intensity versus two frequency axes, the dimensions of which depend on the specific 2D MRS technique. A major goal of this presentation is to give an overview of the basics of 2D MRS and describe several localized 2D MRS sequences which have been implemented on the whole body 1.5T, 3T, and 7T MRI scanners.
M. Thomas

15:10
Data Analysis for 2D MRS: Spectral Fitting

Main goal of in vivo Magnetic Resonance Spectroscopy (MRS) is the determination of individual metabolite concentrations in organs like the brain. Spectrally two-dimensional spectroscopy can help to encode more spectral information during the acquisition, and hence disentangle the overcrowded proton spectra. In order to quantify the 2D spectra most accurately, it is necessary to fit them to 2D metabolite basis spectra, hence utilising the full amount of available prior information. Reasons for fitting along with the actual fitting methods are explained in this educational talk.
Rolf Schulte

15:30
Applications of 2D MRS: Brain & Body

Different types of 2D MRS can offer different types of information to understand the complexities underlying pathophysiology of disease. Technical developments specific to 2D method development and advanced post-processing methods will allow for the identification of biomarkers of diseases at an early stage. Acceleration of signal acquisition, as well as automated data processing algorithms are essential to introduce 2D MRS methods into the clinic.
Saadallah Ramadan

15:50
Break & Meet the Teachers

16:10
Basic Principles and Sequences for Difference and Multiple Quantum Editing

In-vivo proton magnetic resonance spectra exhibit poor spectral resolution due to the overlap of peaks with similar chemical shifts.  Spectral editing techniques have been designed and implemented to enable retention of peaks from metabolites of interest while suppressing background contaminating peaks.  The purpose of the lecture is to describe two important spectral editing techniques, namely, difference editing and multiple quantum filtering.  Basic principles and pulse sequences for each of the methods is presented along with how spatial localization can be incorporated.  In addition, examples of applications of the sequences are provided.      
Atiyah Yahya

16:30
Data Analysis for Spectral Editing

This presentation will cover the major steps required for the analysis of edited spectra, which include the standard steps used for all spectroscopy (Fourier transformation, windowing/filtering, integration/fitting) and some steps that are specifically required by editing (subtraction, frequency-and-phase correction of time-resolved data).
Richard Edden

16:50
Applications of Spectral Editing

Performing proton MR spectroscopy (1H-MRS) at higher static magnetic field strengths (B0) generally improves spectral resolution and, thereby, allows detection of a larger number of metabolites. However, even at very high B0 and in particular on clinical MR scanners the spectral resolution is often not sufficient for an unambiguous quantification of several important J-coupled metabolites such as GABA, GSH, 2GH, Asc, or Lac. Their resonances are strongly overlapping with other more abundant metabolite resonances, which makes their accurate and reliable quantification via conventional 1H-MRS difficult. Spectral editing methods can be applied to selectively quantify these J-coupled metabolites. This opens the window for numerous clinical and neuro-scientific applications.
Wolfgang Bogner

17:10
Roundtable

17:40
Adjournment & Meet the Teachers


Weekend Course

Validation of Structural Measurements with Diffusion MRI

Organizers:Daniel C. Alexander, Ph.D., Derek K. Jones, Ph.D. & Guoying Liu, Ph.D.

Nicoll 2 13:30 - 17:00 Moderators:Geoffrey Parker & Carlo Pierpaoli

13:30
Introduction

13:40
Theoretical Underpinnings of Building a Validation Framework of Diffusion Experiments

Diffusion magnetic resonance is a powerful probe into tissue microstructure. Theoretical investigations commonly focus on establishing the relationships between simplified environments with the magnetic resonance signal. In this talk, the essential tools and a brief description of the building blocks of a comprehensive model of diffusion taking place in tissue will be discussed. Main mathematical approaches will be reviewed at some depth.
Evren Ozarslan

14:10
Numerical Phantoms

Numerical phantoms have played and will continue to play an important role in the development and validation of advanced diffusion MRI techniques.  They complement biological phantoms (in vitro, ex vivo and in vivo) with their controllability and physical phantoms with their flexibility.  This talk will review the aspects of diffusion MRI techniques that have benefited from validation with numerical phantoms and the range of numerical phantoms currently available.  Examples of using numerical phantoms for validating the mapping of tissue microstructure and structural connectivity in the brain will be presented.
Gary Zhang

14:40
Physical hardware phantoms for the validation of diffusion MRI

Physical hardware diffusion phantoms with a well-defined structure, composition and architectural organization can serve as a gold standard for the validation of diffusion MRI. In this lecture, we aim to provide guidelines on how to choose or manufacture a synthetic diffusion phantom that addresses the needs of your project, going from setting up a quality assessment diffusion protocol on a clinical scanner, developing and testing a novel diffusion sequence, validating biophysical models to evaluating tractography models. 
Els Fieremans

15:10
Break & Meet the Teachers

15:30
Validation of Inferences About Tissue Microstructure

Diffusion MRI is unique in its ability to derive microstructural tissue information.  However, since structure is inferred from measurements of diffusion, validating DWI findings with other modalities is important for a complete understanding of diffusion MRI and its relationship to the true underlying tissue microstructure.  This session will provide an overview of methods to validate and quantify the relationship between diffusion MRI findings and the true underlying biology.
Matthew Budde

16:00
Validation of White-Matter Pathways Reconstructed with Diffusion Tractography

This presentation reviews the techniques that can be used to validate WM pathway reconstructions derived from diffusion MRI in humans and non-human primates. The relative merits of the techniques are discussed. The potential for an integrative approach that uses complementary information from chemical tracing in non-human primates, optical imaging in human tissue, as well ex vivo diffusion MRI at microscopic spatial resolutions, is outlined.
Anastasia Yendiki

16:30
Accuracy & Reliability in Population Studies & Clinical Applications

Despite the large body of research studies in humans published using Diffusion MRI, and the availability of very sophisticated models for diffusion MRI data analysis, advanced diffusion MRI applications still have not percolated into clinical practice.  In this talk we will review factors affecting accuracy and reliability of Diffusion MRI that have hindered a larger clinical dissemination of this technique and the most promising solutions to this problem.
carlo pierpaoli

17:00
Panel Discussion & Questions/Comments from the Audience

17:30
Adjournment & Meet the Teachers


Weekend Course

Quantitative Physiology: Imaging Oxygenation

Organizers:Steven Sourbron PhD, Jonathan R. Polimeni, Ph.D. & Eric C. Wong, M.D., Ph.D.

Nicoll 3 13:30 - 16:50 Moderators:Audrey Fan & Andreas Pohlmann

13:30
The Role of Oxygen in Brain Tissue Function

While our brains utilize oxygen and glucose at rapid rates, they have little energy reserves and require constant supplies of glucose and oxygen to maintain normal brain function.  Cerebral blood flow serves as the means through which these energy sources are delivered to the brain.  This presentation will introduce the concepts of cerebral oxygen metabolism, the approaches to measure it, and the applications of these approaches to discern the interplay between CBF, OEF, and CMRO2 in both normal and pathophysiological conditions.  Emphases will be made, when possible, to compare PET and MR approaches that provide similar physiological measures and their in vivo results.    
Weili Lin

14:00
Imaging of Oxygenation Using MR

Quantitative evaluation of brain hemodynamics and metabolism, particularly the relationship between brain function and oxygen utilization, is important for understanding normal human brain operation as well as pathophysiology of neurological disorders. It can also be of great importance for evaluation of hypoxia within tumors of the brain and other organs. Most of the currently used methods are based on measuring blood oxygenation level and directly related to it oxygen extraction fraction, OEF. Combining measurement of OEF with measurement of CBF allows evaluation of oxygen consumption, CMRO2.
Dmitriy Yablonskiy

14:30
Imaging of Oxygenation in the Brain

·       The brain has a uniquely high oxygen metabolic demand, and the ability to noninvasively image brain oxygenation is critical to understand normal brain function and many cerebrovascular and neurological disorders.

·       Three classes of MRI contrast mechanisms to image oxygenation have been explored, including (1) extravascular blood oxygenation level dependent (BOLD); (2) intravascular T2-relaxation; and (3) magnetic susceptibility in cerebral veins. These methods have different abilities to localize regional oxygenation and different strengths and weaknesses.

·       Because MRI methods to image oxygenation are fairly new, additional studies are needed to validate oxygenation measurements with each other, and with the PET reference standard. Promising clinical studies in patients highlight the promise of MRI oxygenation imaging and will benefit from optimized and robust protocols to quantify oxygen metabolism.

Audrey Fan

15:00
Break & Meet the Teachers

15:20
Imaging of Oxygenation in the Kidney

Unlike most organs, in the kidneys, oxygen consumption changes with blood flow and increased blood flow doesn't necessary lead to increased oxygen delivery. This leads to a need for independent measures of perfusion and oxygentation  BOLD MRI is the only non-invasive method to evaluate renal oxygenation.  It is most useful for detecting acute changes following pharmacologic/physiologic maneuvers.  Based on evidence from pre-clinical models, translation to the clinic is being pursued.  Limitations in conventional ROI analysis have been identified, creating an interest in alternative methods, including whole kidney analysis.  Alternate methods to measure oxygenation include electron paramagnetic resonance and fluorine-19 MRI, both involving exogenous materials to be used.
Pottumarthi Prasad

15:50
Imaging of Oxygenation in the Lung

The lung is a gas exchange organ, so it’s primary function is transfer of oxygen from the atmosphere to the blood and CO2 from the blood back to the atmosphere. To quantify this we need more than just measurements of alveolar ventilation (V). We also need to know the capillary perfusion (Q), and most importantly, how well these are matched (the V/Q ratio). In this talk I will focus on some novel methods to image pulmonary ventilation and perfusion with conventional proton MRI, and discuss the technical challenges that need to be overcome to make physiological measurements of lung function.
David Dubowitz

16:20
Imaging of Oxygenation in Tumors

Tumor hypoxia is associated with aggressive phenotypes and resistance to therapy. Several MRI approaches are being developed and evaluated to measure tumor oxygenation. Many use exogenous reporter molecules, whilst some exploit endogenous signal. This review will present strengths and weaknesses in terms of temporal and spatial resolution, precision and accuracy, ease of implementation and robustness of observations. Methods may provide qualitative or quantitative insights including dynamic response to interventions. Some are limited to pre-clinical studies, while others offer ready translation to human patients.
Ralph Mason

16:50
Adjournment & Meet the Teachers


Other

Opening Reception

Exhibition Hall 17:45 - 19:15



Monday, May 9, 2016

Go to top
Plenary Session

Mansfield Lecture

Plenary Hall 8:30 - 9:15

Mansfield Lecture -MR Imaging in Personalised Medicine
XIAOYING WANG1

1PEKING UNIVERSITY FIRST HOSPITAL
XIAOYING WANG


Plenary Session

The MR Value Initiative

Organizers:Mark A. Griswold, Ph.D. & James G. Pipe, Ph.D.

Plenary Hall 8:30 - 10:15 Moderators:James Pipe

Introduction & Membership Thoughts

Panel Discussion - What is Needed Across the World

The High-Value Exam Campaign: A Contest with Consequences

Adjournment


Traditional Poster : Neuro

Exhibition Hall 10:45 - 12:45 (no CME credit)

Electronic Poster : Cancer

Exhibition Hall 10:45 - 11:45 (no CME credit)

Electronic Poster : CV

Exhibition Hall 10:45 - 11:45 (no CME credit)

Study Groups

MR Flow & Motion Quantitation

Hall 405 E 10:45 - 12:45


Study Groups

MR Engineering

Hall 406 D 10:45 - 12:45


Power Pitch

Diffusion at the Cutting Edge

Power Pitch Theatre, Exhibition Hall 10:45 - 11:45 Moderators:Robin Heidemann & Yi-Fen Yen

1 10:45
DWI^2: exploring the MRI-phase for imaging diffusion
Ralph Sinkus1, Simon Auguste Lambert1, Lucas Hadjilucas1, Shaihan Malik2, Anirban Biswas1, Francesco Padormo2, Jack Lee1, and Joseph V Hajnal2

1Imaging Sciences & Biomedical Engineering Division Kings College, King's College London, London, United Kingdom, 2Centre for the Developing Brain & Department Biomedical Engineering, King's College London, London, United Kingdom

2 10:48
High resolution diffusion tensor reconstruction from simultaneous multi-slice acquisitions in a clinically feasible scan time
Gwendolyn Van Steenkiste1, Ben Jeurissen1, Steven Baete2,3, Arnold J den Dekker1,4, Dirk H.J. Poot5,6, Fernando Boada2,3, and Jan Sijbers1

1iMinds-Vision Lab, University of Antwerp, Antwerp, Belgium, 2Center for Advanced Imaging Innovation and Research (CAI2R), NYU School of Medicine, New York, NY, United States, 3Center for Biomedical Imaging, Department of Radiology, NYU School of Medicine, New York, NY, United States, 4Delft Center for Systems and Control, Delft University of Technology, Delft, Netherlands, 5Imaging Science and Technology, Delft University of Technology, Delft, Netherlands, 6Biomedical Imaging Group Rotterdam, Erasmus Medical Center Rotterdam, Rotterdam, Rotterdam, Netherlands

3
10:51
Quantitative evaluation of eddy-current and motion correction techniques for diffusion-weighted MRI
Mark S Graham1, Ivana Drobnjak1, and Hui Zhang1

1Centre for Medical Image Computing & Department of Computer Science, UCL, London, United Kingdom

4 10:54
A Mathematical Model and an Efficient Simulation Framework for Diffusion Cardiac Imaging: Application to Quantification of Cardiac Deformation on the Diffusion Signal
Imen Mekkaoui1, Kévin Moulin2,3, Jérôme Pousin1, and Magalie Viallon2,4

1ICJ, INSA-Lyon, Villeurbanne, France, 2Creatis, INSA-Lyon, Lyon, France, 3Siemens Healthcare, Saint-Denis, France, 4Department of Radiology, Université J. Monnet, Saint Etienne, France

5
10:57
Diffusion Kurtosis at varying diffusion times in the normal and injured mouse brains
Dan Wu1, Frances J Northington2, and Jiangyang Zhang1,3

1Radiology, Johns Hopkins University School of Medicine, BALTIMORE, MD, United States, 2Pediatrics, Johns Hopkins University School of Medicine, BALTIMORE, MD, United States, 3Radiology, New York University School of Medicine, New Yourk, NY, United States

6 11:00
Can  the  Stretched  Exponential  Model  of  Gas  Diffusion  Provide Clinically -Relevant Parenchyma  Measurements of Lung Disease?
Alexei Ouriadov1, Eric Lessard1, David G McCormack2, and Grace Parraga1

1Robarts Research Institute, The University of Western Ontario, London, ON, Canada, 2Department of Medicine, The University of Western Ontario, London, ON, Canada

7 11:03
Overestimation of CSF fraction in NODDI: possible correction techniques and the effect on neurite density and orientation dispersion measures
Samira Bouyagoub1, Nicholas G. Dowell1, Samuel A. Hurley2, Tobias C. Wood3, and Mara Cercignani1

1Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom, 2FMRIB Centre, University of Oxford, Oxford, United Kingdom, 3Neuroimaging, IoPPN, King’s College London, London, United Kingdom

8 11:06
Quantitative Assessment of Microstructure Properties of Human Corpus Callosum and Distinct Connectivity to Projected Cortices using Parametric T1 Imaging and Diffusion Tractography
Byeong-Yeul Lee1, Xiao-Hong Zhu1, and Wei Chen1

1Center for Magnetic Resonance Research, Radiology, University of Minnesota, Minneapolis, MN, United States

9
11:09
Fibre directionality and information flow through the white matter: Preliminary results on the fusion of diffusion MRI and EEG
Samuel Deslauriers-Gauthier1, Jean-Marc Lina2, Russell Butler3, Kevin Whittingstall3, Pierre-Michel Bernier4, and Maxime Descoteaux1

1Computer Science department, Université de Sherbrooke, Sherbrooke, QC, Canada, 2École de Technologie Supérieure, Montréal, QC, Canada, 3Department of Diagnostic Radiology, Université de Sherbrooke, Sherbrooke, QC, Canada, 4Department of Kinanthropology, Université de Sherbrooke, Sherbrooke, QC, Canada

10
11:12
Improved tractography by modelling sub-voxel fibre patterns using asymmetric fibre orientation distributions
Matteo Bastiani1, Michiel Cottaar1, Krikor Dikranian2, Aurobrata Ghosh3, Hui Zhang3, Daniel C. Alexander3, Timothy Behrens1, Saad Jbabdi1, and Stamatios N. Sotiropoulos1

1FMRIB Centre, University of Oxford, Oxford, United Kingdom, 2Department of Anatomy & Neurobiology, Washington University, St. Louis, MO, United States, 3Department of Computer Science & Centre for Medical Image Computing, University College London, London, United Kingdom

11 11:15
Investigation of the influence of the extracellular matrix on water diffusion in brain and cartilage
Jakob Georgi1, Riccardo Metere1, Markus Morawski2, Carsten Jäger2, and Harald E. Möller1

1Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 2Paul-Flechsig-Institute for Brain Research, Leipzig, Germany

12 11:18
Measurement of the Effect of Tissue Fixation on Tumour Microstructure using VERDICT Diffusion-MRI
Ben Jordan1, Tom Roberts1, Angela D'Esposito1, John Connell1, Andrada Ianus2, Eleftheria Panagiotaki2, Daniel Alexander2, Mark Lythgoe1, and Simon Walker-Samuel1

1Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom, 2Centre for Medical Image Computing, University College London, London, United Kingdom

13
11:21
Validation of Surface-to-Volume Ratio derived from Oscillating Gradient Spin Echo on a clinical scanner using anisotropic fiber phantoms
Gregory Lemberskiy1, Steven H. Baete1, Martijn A. Cloos1, Dmitry S. Novikov1, and Els Fieremans1

1Radiology, NYU School of Medicine, New York, NY, United States

14
11:24
Demonstration of a Sliding-Window Diffusion Tensor Technique for Temporal Study of Post-Exercise Skeletal Muscle Dynamics
Conrad P Rockel1,2 and Michael D Noseworthy1,2,3

1School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada, 2Imaging Research Centre, St Josephs Healthcare, Hamilton, ON, Canada, 3Electrical and Computer Engineering, McMaster University, Hamilton, ON, Canada

15 11:27
Denoising Diffusion-Weighted Images Using x-q Space Non-Local Means
Geng Chen1,2, Yafeng Wu1, Dinggang Shen2, and Pew-Thian Yap2

1Data Processing Center, Northwestern Polytechnical University, Xi'an, China, People's Republic of, 2Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States


Oral

MRS Methods: What's New?

Room 300-302 10:45 - 12:45 Moderators:Graham Galloway & Naranamangalam Jagannathan

16
10:45
Characterization of the macromolecular baseline with a metabolite-cycled double-inversion recovery sequence in the human brain at 9.4T
Ioannis Angelos Giapitzakis1,2, Roland Kreis 3, and Anke Henning 1,4

1Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 2IMPRS for Cognitive and Systems Neuroscience, University of Tuebingen, Tuebingen, Germany, 3Depts. Radiology and Clinical Research, University of Bern, Bern, Switzerland, 4Institute of Biomedical Engineering, University and ETH, Zürich, Switzerland

Macromolecular resonances (MM) overlap with metabolites resulting in inaccurate quantification of the metabolites due to baseline distortion. This effect becomes even more severe in case of short echo times (TE). The purpose of this study was the development of an adiabatic pulse for double inversion recovery and investigation of impact to include MM into quantification of 9.4T MRS data of human brain. This is the first study where MC-STEAM is combined with a double inversion technique. The results showed the advantages of UHF and MC as well as the necessity of the inclusion of MM baseline in the basis set.

17 10:57
Evidence for regional and spectral differences of macromolecule signals in human brain using a crusher coil at 7 Tesla
Nicolas Geades1, Carrie Wismans2, Mariska Damen2, Penny Gowland1, Hans Hoogduin2, Vincent Boer2, Dennis Klomp2, and Jannie Wijnen2

1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, 2Department of Radiology, University Medical Centre Utrecht, Utrecht, Netherlands

The regional, spectral and relaxation differences of macromolecules (MM) in the human brain were investigated using T1 mapping, metabolite nulling and high resolution MRSI with a crusher coil at 7T. Differences between macromolecular signal of GM and WM were observed by all three methods. The T1 mapping showed different T1 relaxation time of MM in GM and WM. Metabolic maps created by fitting an averaged WM spectrum showed differences in M1 and M2. The macromolecules in the metabolite nulled data showed a different M4 in GM and WM. Some of these differences can be explained by differences in T1 relaxation.

18
11:09
Improvement of 2-hydroxyglutarate detectability using optimized triple-refocusing difference editing at 7T in vivo
Sandeep K Ganji1, Zhongxu An1, Vivek Tiwari1, Marco Pinho2, Edward Pan3, Bruce Mickey4, Elizabeth Maher5, and Changho Choi1

1Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States, 2Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 3Neurology and Neurotherapeutic, UT Southwestern Medical Center, Dallas, TX, United States, 4Neurological Surgery, UT Southwestern Medical Center, Dallas, TX, United States, 5Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States

2-hydroxyglutarate (2HG) has become an important biomarker in the diagnosis and management of glioma patients as well as in the workup of an undiagnosed mass. The 1H MRS signals of 2HG are extensively overlapped with other metabolite signals. Specifically, uncertainty in 2HG evaluation arising from the spectral overlap of the 2HG 2.25-ppm signal with the GABA 2.29-ppm resonance may be a major obstacle when the 2HG level is relatively low. Here we report a novel triple-refocusing difference editing that provides complete differentiation between 2HG and GABA signals at 7T. 

19
11:21
Indirectly-Detected and Spin-Amplified Heteronuclear MRS and MRI
Chencai Wang1, Chaohsiung Hsu1, Stephanie Wolohan1, and Yung-Ya Lin1

1Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA, United States

A general indirect-detection and spin-amplification scheme has been developed to enhance the sensitivity of heteronuclear MRS and MRI based on dynamic instability of the solvent proton magnetization under collective feedback fields of radiation damping and the distant dipolar field. The heteronuclear solute spins are first detected by the solvent proton spins through various magnetization transfer mechanisms and serve as small “input” signals to perturb the solvent proton magnetization, which is prepared in an unstable state. The weakly detected signal is then amplified through subsequent nonlinear evolution of the solvent proton magnetization to achieve 10x SNR improvement for 13C MRS and MRI.

20
11:33
Remodeling of energy metabolism revealed by 31P magnetization transfer in a transgenic rat model of Huntington’s disease
Brice Tiret1,2, Maria-Angeles Carrillo-de Sauvage1,2, Huu Phuc Nguyen3,4, Nicole El Massioui5,6, Valérie Doyère5,6, Vincent Lebon1,2, Emmanuel Brouillet1,2, and Julien Valette1,2

1CEA/DSV/I2BM/MIRCen, Fontenay-aux-Roses, France, 2CNRS Université Paris-Saclay UMR 9199, Fontenay-aux-Roses, France, 3Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany, 4Centre for Rare Diseases, University of Tuebingen, Tuebingen, Germany, 5Paris-Saclay Institute of Neuroscience, Université Paris-Sud, UMR 9197, Orsay, France, 6Centre National de la Recherche Scientifique, Orsay, France

Localized 31P MRS with progressive magnetization transfer (MT) is performed in the BACHD transgenic rat model of Huntington’s disease to assess energy metabolism. Localized measurements of the ATP formation rate through creatine kinase and oxidative phosphorylation (ATPsynthase) are performed in the rat brain for the first time. Results show that ATPsynthase rate is reduced by a factor 2, which is partly compensated by higher cerebral concentrations of phosphocreatine to generate ATP via creatine kinase.

21 11:45
Investigating machine learning approaches for quality control of brain tumor spectra
Sreenath P Kyathanahally1, Victor Mocioiu2, Nuno Miguel Pedrosa de Barros3, Johannes Slotboom3, Alan J Wright4, Margarida Julià-Sapé 2, Carles Arús2, and Roland Kreis1

1Depts. Radiology and Clinical Research, University of Bern, Bern, Switzerland, 2Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Universitat Autònoma de Barcelona, Barcelona, Spain, 3DRNN, Institute of Diagnostic and Interventional Neuroradiology/SCAN, University Hospital Bern, Bern, Switzerland, 4CRUK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom

Despite many potential applications of MR spectroscopy in the clinic, its usage is limited – and the need for human experts to identify bad quality spectra may contribute to this. Previous studies have shown that machine learning methods can be developed to accept or reject a spectrum automatically. In this study, we extend this to different machine learning methods on 1916 spectra from the eTUMOUR and INTERPRET databases. The RUSBoost classifier, which handles unbalanced data, improved specificity and accuracy compared to other classifiers, in particular in combination with an extended feature set and multi-class labels.

22 11:57
Automatic quality assessment of short and long-TE brain tumour MRSI data using novel Spectral Features
Nuno Miguel Pedrosa de Barros1,2, Urspeter Knecht1, Richard McKinley1, Jonathan Giezendanner1, Roland Wiest1, and Johannes Slotboom1

1Institute for Diagnostic and Interventional Neuroradiology, Inselspital, Bern, Switzerland, 2University of Bern, Bern, Switzerland

MRSI-data frequently contains bad-quality spectra which strongly limits its clinical-use. Current clinical practice in our institute is that these bad-quality spectra are filtered out by an MRS-expert, at the expense of long processing times. In this work we present a new method for automatic quality assessment of both long and short-TE MRSI brain tumour data. This method is based upon a novel set of spectral features, and it is as accurate as an expert but considerably faster (3/4 minutes vs 3seconds).

23 12:09
Fast frequency–sweep spectroscopic imaging with an ultra-low flip angle
Junyu Guo1, Zoltan Patay1, and Wilbrun E. Reddick1

1St Jude Children's Research Hospital, Memphis, TN, United States

We present a novel, simple and fast MR spectroscopic imaging technique and show its conceptual validation with simulations and demonstrate proof-of-principle with phantom and human studies. First, compared to the conventional spectroscopic imaging in the time-domain, our method acquires data in the frequency domain, allowing flexible non-uniform sampling to speed up the acquisition. Second, using ultra-small RF pulses offers intrinsic water and fat suppression, greatly simplifying the scanning procedures. Third, this new technique has hundreds of times lower energy deposition than conventional MRI scans. We believe our method could allow spectroscopic imaging to play a larger role in clinical applications.

24 12:21
Parameterization of measured macromolecular background in ultra-short acquisition delay 1H MRSI in the brain at 7T
Michal Považan1,2, Gilbert Hangel1, Bernhard Strasser1, Eva Heckova1, Lukas Hingerl1, Stephan Gruber1, Siegfried Trattnig1,2, and Wolfgang Bogner1

1High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria, 2Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria

Ultra-short echo/acquisition delay MRS spectra have a strong characteristic background consisting of macromolecule (MM) resonances superimposed on the signal of metabolites. Typically a single metabolite-nulled MM spectrum is included into quantification routine to account for this. To detect  more prominent regional and pathologic changes, we replaced this single MM spectrum by individual MM peaks. We found that the MM peaks in a 2.3-0.5 ppm region are higher in gray matter compared to white matter, whereas the MM peaks from 2.9 to 3.2 ppm were significantly higher in white matter of healthy volunteers and one MS patient.

25 12:33
Stochastic excitation scheme for estimating longitudinal relaxation and radiofrequency transmit inhomogeneity in single voxel spectroscopy
Assaf Tal1

1Chemical Physics, Weizmann Institute of Science, Rehovot, Israel

A stochastic excitation and corresponding dictionary matching  scheme is presented for  quantifying metabolite concentrations, longitudinal relaxation times and transmit inhomogeneity in single voxel proton magnetic resonance spectroscopy in the human brain.


Oral

Magnetic Susceptibility

Room 324-326 10:45 - 12:45 Moderators:Berkin Bilgic

26 10:45
An illustrated comparison of background field elimination methods for phase MRI and QSM
Ferdinand Schweser1,2, Wei Li3, Hongfu Sun4, Dong Zhou5, Nicola Bertolino1, Paul Polak1, Yi Wang5, Alan H Wilman4, Kristian Bredies6, Robert Zivadinov1, and Simon Daniel Robinson7

1Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States, 2MRI Molecular and Translational Research Center, Jacobs School of Medicine and Biomedical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States, 3Research Imaging Institute, The University of Texas Health Science Center, San Antonio, TX, United States, 4Department of Biomedical Engineering, University of Alberta, Edmonton, AB, Canada, 5Department of Radiology, Weill Cornell Medical College, New York, NY, United States, 6Institute for Mathematics and Scientific Computing, University of Graz, Graz, Austria, 7High Field MR Center of Excellence, Department of Radiology, Medical University of Vienna, Vienna, Austria

Elimination of background fields is an essential step in phase MRI and QSM, with many different approaches proposed over the past years. However, it is currently unclear how the various methods perform relative to each other and what their respective strengths and weaknesses are, because a multi-center quantitative comparison of all techniques has not yet been carried out.

In this work we quantitatively compare inverse Laplace filtering, SHARP , V-SHARP, iSMV , LBV, HARPERELLA, iHARPERELLA, PDF, and RE-SHARP in a collaborative effort.

The background correction performance was similar with all methods, with iSMV and LBV yielding the best results.


27
10:57
Fast Unwrapping using Discrete Gradient Evaluation (FUDGE): an analytical correction to the Laplacian-based phase unwrapping technique for discrete data.
Amanda Ching Lih Ng1, Meei Pyng Ng2, Sonal Josan3, Shawna Farquharson4, Claire Mulcahy4, and Roger J Ordidge1

1Dept of Anatomy & Neuroscience, The University of Melbourne, Parkville, Australia, 2Dept of Mathematics & Statistics, The University of Melbourne, Parkville, Australia, 3Siemens Healthcare, Melbourne, Australia, 4Imaging, The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia

Laplacian-based phase unwrapping is commonly used to pre-process phase for methods such as Quantitative Susceptibility Mapping (QSM). However, the formulation was derived with the assumption of a continuous signal and a continuous Fourier transform. When applied to discrete MRI phase data, serious errors in phase can occur, resulting in substantial errors in QSM estimates. We present a mathematically correct Laplacian-based phase unwrapping formula, based on the assumption of the discrete nature of MRI phase data and processing. Our results reflect the mathematical predictions of the old and new formulations.

28
11:09
Imaging Whole Mouse Brain Cytoarchitecture by Quantitative Susceptibility Mapping at 10-μm Resolution
Hongjiang Wei1, Luke Xie2, Russell Dibb3, Wei Li4, Kyle Decker3, G. Allan Johnson3,5, and Chunlei Liu1,5

1Brain Imaging and Analysis Center, Duke University, Durham, NC, United States, 2Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, UT, United States, 3Center for In Vivo Microscopy, Duke University, Durham, NC, United States, 4Research Imaging Institute, University of Texas Health Science Center, San Antonio, TX, United States, 5Department of Radiology, School of Medicine, Duke University, Durham, NC, United States

In this study, we demonstrate that whole brain cytoarchitecture can be revealed by QSM at 10-μm resolution at 9.4T. Using QSM, we are able to reveal exquisite anatomical details such as retina layers of the eyeball, glomeruli in olfactory bulb, barrel cortex, medium-sized spiny neurons in striatum, cell layers of cerebellum, and hippocampus. This ultra-high resolution QSM of the intact mouse brain is a powerful dataset to allow analysis and visualization of the brain cytoarchitecture in 3D.

29
11:21
A Novel Method for Background Field Removal in Abdominal QSM
Debra E. Horng1,2, Samir D. Sharma1, Scott B. Reeder1,2,3,4,5, and Diego Hernando1

1Radiology, University of Wisconsin, Madison, WI, United States, 2Medical Physics, University of Wisconsin, Madison, WI, United States, 3Medicine, University of Wisconsin, Madison, WI, United States, 4Biomedical Engineering, University of Wisconsin, Madison, WI, United States, 5Emergency Medicine, University of Wisconsin, Madison, WI, United States

We introduce a QSM background field removal method based on harmonic function theory. Methods based on the mean value theorem compute the value at the center of a spherical kernel. Conversely, a new method based on the extended Poisson kernel can compute the value at any location in a spherical kernel. The new kernel is evaluated for accuracy near air/tissue interfaces, resulting in low errors compared to existing methods. Our new method is fast (analytic) and is designed for performance near air/tissue interfaces in abdominal QSM.

30 11:33
Toward Iron Distribution Mapping using Quantitative Susceptibility Mapping (QSM): A Comparison of Histological Iron Concentration Maps with Magnetic Susceptibility Maps
Andreas Deistung1, Verena Endmayr2, Simon Hametner2, Hans Lassmann2, Jürgen Rainer Reichenbach1, Simon Daniel Robinson3, Thomas Haider4, Hannes Traxler5, Evelin Haimburger6, Siegfried Trattnig3, and Günther Grabner3,6

1Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital – Friedrich Schiller University Jena, Jena, Germany, 2Center for Brain Research, Medical University of Vienna, Vienna, Austria, 3High Field Magnetic Resonance Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 4University Clinic for Trauma Surgery, Medical University of Vienna, Vienna, Austria, 5Center of Anatomy and Cellbiology, Medical University of Vienna, Vienna, Austria, 6Department of Health Sciences and Social Work, Carinthia University of Applied Sciences, Klagenfurt, Austria

Quantitative susceptibility mapping (QSM) provides a unique view into cerebral iron distribution in vivo. However, not only paramagnetic iron complexes but also diamagnetic myelin around axons contribute to the magnetic susceptibility. To further validate QSM for iron mapping we present a histochemical-driven approach to quantify iron in post mortem brain tissue and compare the spatial distribution of iron with in situ magnetic susceptibility maps. Direct comparison between histological iron concentration and susceptibility maps revealed excellent correspondence between iron accumulations and elevated susceptibility in deep gray matter and can improve the understanding of biophysical origins of susceptibility variations within brain tissue.

31 11:45
Feasibility Study of High Resolution Mapping for Myelin Water Fraction and Frequency Shift using Tissue Susceptibility
Zhe Wu1,2, Hongjian He1,2, Ying Chen1,2, Song Chen1,2, Hui Liu3, Yiping P. Du2, and Jianhui Zhong1,2

1Center for Brain Imaging Science and Technology, Zhejiang University, Hangzhou, China, People's Republic of, 2Department of Biomedical Engineering, Zhejiang University, Hangzhou, China, People's Republic of, 3NEA MR Collaboration, Siemens Ltd., China, Shanghai, China, People's Republic of

A three-step method for high resolution myelin water fraction (MWF) and frequency shift mapping of white matter components using tissue susceptibility is presented in this study. Tissue susceptibility induced phase was calculated by the simultaneously acquired QSM from the same multi-echo GRE (mGRE) dataset, and was used as the phase part of complex data for a subsequent fitting to a three-pool white matter model.  Benefit from the background phase removal and magnetic dipole deconvolution procedures during QSM calculation, the result reveals much less misfitting when comparing with direct fitting to original mGRE data. These generated quantitative maps can be potentially used for quantitative studies of demyelinated diseases.

32 11:57
Preconditioned QSM to Determine a Large Range of Susceptibility Over The Entire Field Of View from Total Field
Zhe Liu1, Youngwook Kee2, Dong Zhou2, Pascal Spincemaille2, and Yi Wang1,2

1Biomedical Engineering, Cornell University, Ithaca, NY, United States, 2Radiology, Weill Cornell Medical College, New York, NY, United States

We propose a Preconditioned QSM calculating susceptibility over the entire field of view (FOV), which eliminates the errors associated with background field removal. The background is regarded as part of the region with large susceptibilities, which is determined by a preconditioned conjugate gradient solver with enhanced convergence. Our data demonstrate that our preconditioned QSM provides a susceptibility map of the entire head accurately depicting skin, bone, air filled sinuses and hemorrhages.

33 12:09
MRI in Multiple Sclerosis: The curiosity of apparent susceptibility increases at simultaneous iron loss
Vanessa Wiggermann1,2, Simon Hametner3, Enedino Hernandez-Torres2,4, Verena Endmayr3, Christian Kames5, and Alexander Rauscher2

1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2Pediatrics, University of British Columbia, Vancouver, BC, Canada, 3Neuroimmunology, Medical University of Vienna, Vienna, Austria, 4UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada, 5Engineering Physics, University of British Columbia, Vancouver, BC, Canada

Quantitative Susceptibility Mapping has shown great potential to be used for clinical diagnoses due to its high sensitivity to change and high spatial resolution. Notably, the ability to quantify damage has been appealing. However, attributing susceptibility increases or decreases to certain mechanisms has been challenging. In particular, interpretation of MR signal changes during multiple sclerosis lesion formation is lacking consistency and histological validation. Here, we investigated the hypothesis that apparent changes of the lesion tissue may be in fact due to changes in the lesions vicinity and caution is required when interpreting the quantitative susceptibility signal in multiple sclerosis lesions.

34 12:21
Quantitative susceptibility mapping of the rat brain after traumatic brain injury
Karthik Chary1, Mikko J. Nissi2,3, Ramón I. Rey4, Eppu Manninen1, Karin Shmueli5, Alejandra Sierra1, and Olli Gröhn1

1Department of Neurobiology, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland, 2Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, 3Finland Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland, 4Department of Neurology, Clinical Neurosciences Research Laboratory, Hospital Clínico Universitario, Health Research Institute of Santiago de Compostela (IDIS), University of Santiago de Compostela, Santiago de Compostela, Spain, 5Department of Medical Physics & Biomedical Engineering, University College London, London, United Kingdom

Our aim was to test the sensitivity of QSM to demyelination, iron and calcifications in a rat model of TBI. Ex vivo QSM data were obtained from five injured and four sham control rats, six months after TBI. Our results showed susceptibility changes in white matter areas consistent with myelin staining. Perilesional cortex became more diamagnetic after TBI. Thalamic nuclei showed variable responses as diamagnetic calcification and paramagnetic iron accumulation occurred in the same brain areas. Overall, QSM showed sensitivity to TBI changes. However, further studies are required to better understand the influence of potentially counteracting pathological processes.

35 12:33
Suitable reference tissues for quantitative susceptibility mapping of the brain
Sina Straub1, Till Schneider2,3, Martin T. Freitag3, Christian H. Ziener3, Heinz-Peter Schlemmer3, Mark E. Ladd1, and Frederik B. Laun1

1Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany, 3Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany

Since QSM is only able to quantify magnetic susceptibility relative to a reference value, a suitable reference tissue must be available to be able to compare different subjects and stages of disease. To find such a suitable reference tissue for QSM of the brain, melanoma patients with and without brain lesions were measured. 12 reference tissues were chosen and assessed in multiple measurements of the same patient and amongst different patients. The posterior limb of the internal capsule and a cerebrospinal fluid volume in the atrium of the lateral ventricles appeared to be most suitable reference tissues.


Oral

Young Investigator Awards

Room 331-332 10:45 - 12:45 Moderators:Brian Hargreaves & Jennifer McNab

36 10:45
Music-Based Magnetic Resonance Fingerprinting to Improve Patient Comfort During MRI Examinations
Dan Ma1, Eric Y. Pierre2, Yun Jiang 2, Mark D. Schluchter3, Kawin Setsompop4, Vikas Gulani1, and Mark Griswold1

1Radiology, Case Western Reserve University, Cleveland, OH, United States, 2Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, 3Epidemiology & Biostatistics, Case Western Reserve University, Cleveland, OH, United States, 4A.A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States

An acquisition method named MRF-Music is proposed to mitigate the acoustic noise during MRI scans by producing musical sounds directly from the switching magnetic fields while simultaneously quantifying multiple important tissue properties. MP3 music files were converted to arbitrary encoding gradients, which were then used with varying flip angles and TRs in both 2D and 3D MRF exam to generate T1, T2 and proton density maps. The MRF-Music scans were shown to significantly improve patients’ comfort. T1 and T2 measured from phantom and in vivo scans were also in good agreement with those from the standard measurements and reported values. 

37 11:05
Simultaneous assessment of cardiac metabolism and perfusion using co-polarized [1-13C]pyruvate and 13C-urea
Angus Zoen Lau1,2, Jack Miller2,3, Matthew D Robson1, and Damian J Tyler1,2

1Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, 2Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom, 3Department of Physics, Clarendon Laboratory, Oxford, United Kingdom

Assessment of cardiac metabolism and perfusion using hyperpolarized 13C substrates enables discrimination between viable, hibernating, and non-viable tissue, but current methods require two separate injections of pre-polarized [1-13C]pyruvate and 13C-urea, respectively. We propose to use an infusion of co-polarized [1-13C]pyruvate/13C-urea combined with a flow-sensitized pulse sequence to simultaneously assess both of these parameters in a single injection. Perfusion and metabolic state are modulated using specific interventions, and subsequently detected using the new scan. This probe of both myocardial perfusion and metabolism is anticipated to enable metabolic study of the heart in acute scenarios.

38 11:25
xSPEN: Single-shot magnetic resonance imaging with exceptional resilience to field heterogeneities
Zhiyong Zhang1, Amir Seginer1, and Lucio Frydman1

1Chemical Physics, Weizmann Institute of Science, Rehovot, Israel

Single-shot MRI has been constrained to acquisitions in quality magnets and homogeneous tissues. The present study introduces a methodology that can deliver such images with good SNR, under much poorer field and/or multiple shift conditions. These capabilities are achieved based on new principles whereby images are read using field gradients that are not applied along the direction being encoded. This enables one to accommodate shifts/inhomogeneities into the single-scan image generation protocol, without suffering from miss-registrations, without requiring a priori information for post-acquisition corrections, and without demanding specialized instrumentation. This enables new single-shot investigations that have hitherto escaped from MRI’s scope.

39 11:45
Evaluation of Upper Airway Collapsibility Using Simultaneous Multi-Slice Real-Time MRI
Ziyue Wu1,2, Weiyi Chen1, Michael C.K. Khoo1, Sally L. Davidson Ward3, and Krishna S. Nayak1

1University of Southern California, Los Angeles, CA, United States, 2Alltech Medical Systems, Solon, OH, United States, 3Children's Hospital Los Angeles, Los Angels, CA, United States

We present a method for simultaneous multi-slice airway collapsibility measurement based on sparse golden-angle radial CAIPIRINHA, with acceleration factor up to 33.3. We present data from patients with obstructive sleep apnea and normal controls.  One interesting finding is that a narrower airway site does not always correspond to higher collapsibility. This finding may be of interest to sleep surgeons. Our results also suggest that both compliance and Pclose were significantly different between healthy controls and OSA patients (P<0.001), and both measures can potentially serve as biomarkers.

40 12:05
Interstudy repeatability of self-gated quantitative myocardial perfusion MRI
Devavrat Likhite1, Promporn Suksaranjit2, Ganesh Adluru1, Nan Hu3, Cindy Weng3, Eugene Kholmovski1, Chris McGann2, Brent Wilson2, and Edward DiBella1

1Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, UT, United States, 2Division of Cardiovascular Medicine, University of Utah, Salt Lake City, UT, United States, 3Department of Internal Medicine, University of Utah, Salt Lake City, UT, United States

Dynamic contrast enhanced MRI is maturing as a tool in contemporary cardiovascular medicine. A self-gated method that avoids the use of ECG-gating signal has been validated by us for quantitative myocardial perfusion. Our most recent study looks at the inter-study repeatability of this quantitative self-gated method. Our findings show that the multi-slice self-gated (near-systole) approach has a comparable or better repeatability than published ECG-gated single slice studies. The purpose of this abstract is to summarize these findings from our recent work, highlighting the simplicity, ease of use and reliability of the self-gated method for quantitative myocardial perfusion.

41 12:25
Neurovascular uncoupling in resting state fMRI demonstrated in patients with primary brain gliomas
Shruti Agarwal1, Haris I. Sair1, Noushin Yahyavi-Firouz-Abadi1, Raag Airan1, and Jay J. Pillai1

1Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States

One of the most important potential limitations of presurgical mapping using blood oxygen level dependent functional magnetic resonance imaging (BOLD fMRI) is the phenomenon of neurovascular uncoupling (NVU). NVU can lead to erroneous interpretation of clinical fMRI examinations. The effects of brain tumor-related NVU on task-based BOLD fMRI have been previously published. The purpose of this study is to demonstrate that the problem of brain tumor-related NVU is a significant issue with respect to resting state BOLD fMRI similar to task-based BOLD fMRI, in which signal detectability can be compromised by breakdown of normal neurovascular coupling.


Oral

Artefacts: System Imperfections & Implants

Room 334-336 10:45 - 12:45 Moderators:Pablo Irarrazaval & Dinghui Wang

42
10:45
Evolution-time encoded single-scan cross spatiotemporal encoding imaging near metal implants
Zhiyong Zhang1,2, Amir Seginer1, and Lucio Frydman1

1Chemical Physics, Weizmann Institute of Science, Rehovot, Israel, 2Electronic Science, Xiamen University, Xiamen, China, People's Republic of

Magnetic resonance imaging (MRI) near metallic implants remains an unmet need because of severe artifacts, which mainly stem from large metal-induced field inhomogeneities. The single-scan cross spatiotemporal encoding (xSPEN) technique delivers in-plane distortion-free 2D images under such large field inhomogeneity condition, while the slice-plane displacement, “signal voids” and “pile-up” effects are proposed to be solved by applying t1-evolution-time encoding on the multi-slicing 2D xSPEN technique. Compared to the popular “SEMAC” and “MAVIC” techniques, the remarkable time efficiency of this t1-encoding xSPEN thus enable many advanced MRI applications near metal implants with another additional dimension, such as diffusing MRI, function MRI.

43 10:57
Fast Fourier transform-based susceptibility-to-B0 calculation without aliasing artifacts
Lee Seungkyun1,2

1Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon, Korea, Republic of, 2Department of Biomedical Engineering, Sungkyunkwan University (SKKU), Suwon, Korea, Republic of

In the Fourier transform-based susceptibility-to-B0 calculation, the dipolar field kernel (1/3-kz2/k2) is discretely sampled in the k-space, which leads to aliasing artifacts in the spatial domain. We show that calculating and discretizing the dipolar field kernel in the spatial domain, before the Fourier transform, can effectively reduce the aliasing effect without resorting to large zero-filled buffers. In particular, aliasing is eliminated if the spatial-domain grid size is larger than the combined dimensions of the susceptibility source and the B0 target regions. The new method can accelerate repeated calculations of susceptibility-induced B0 fields.

44 11:09
Concomitant gradient effects on chemical shift encoded imaging
Timothy J Colgan1,2, Diego Hernando1, Samir D Sharma1, Ann Shimakawa3, and Scott B Reeder1,2,4,5,6

1Radiology, University of Wisconsin, Madison, WI, United States, 2Medical Physics, University of Wisconsin, Madison, WI, United States, 3Global Applied Science Lab, GE Healthcare, Menlo Park, CA, United States, 4Biomedical Engineering, University of Wisconsin, Madison, WI, United States, 5Medicine, University of Wisconsin, Madison, WI, United States, 6Emergency Medicine, University of Wisconsin, Madison, WI, United States

Quantitative chemical shift-encoded (CSE) MRI techniques acquire complex-valued (magnitude and phase) images at multiple echo times (TE), enabling simultaneous mapping of fat-fraction, R2* (=1/T2*) and B0 field. Applications of CSE-MRI include tissue fat quantification, iron quantification and quantitative susceptibility mapping (QSM). Recently, phase shifts due to concomitant gradients (CG) have been identified as a source of error for quantitative CSE techniques, so their effects on fat-fraction, R2* and B0 maps are characterized in this study.   CG correction of experimental data demonstrates that the detrimental effects of CG phase shifts can be removed before reconstruction to produce more accurate estimates of the fat-fraction, R2*, and field map measurements.


45 11:21
Real-Time Field Control Using Full 3rd-Order Matrix Pre-Emphasis
Yolanda Duerst1, Bertram J. Wilm1, Benjamin E. Dietrich1, Simon Gross1, Thomas Schmid1, David O. Brunner1, and Klaas P. Pruessmann1

1ETH Zurich, Zurich, Switzerland

Update steps of real-time field control suffer from imperfect shim responses which degrade control quality. By including full 3rd-order matrix pre-emphasis as an additional filter in the control loop, all self-term responses are shaped to be equal and all cross-term responses are directly suppressed. This leads to disturbances being rejected faster and less noise amplification. Thus enables better field control in demanding situations such as caused by disturbance of high spatial and temporal variability.

46 11:33
Reducing Brain MRI Artifacts Caused by Ferromagnetic Orthodontic Appliances Using Permanent Magnets
Zhiyue J Wang1,2, Yong Jong Park1,2, Youngseob Seo1,2, Michael C Morriss1,2, and Nancy K Rollins1,2

1UT Southwestern Medical Center, Dallas, TX, United States, 2Children's Medical Center, Dallas, TX, United States

Stainless steel orthodontic appliances are commonly found in adolescents undergoing clinical brain MRI examinations. They cause severe magnetic susceptibility artifacts and failure to obtain diagnostic information from many MR techniques. The B0 shimming capability present on clinical MR scanners cannot remove these artifacts. We have constructed devices for the correction of these artifacts at 1.5 T using small pieces of permanent magnets mounted on intra-oral mouth guards or an extra-oral mouth-band. The magnetic field from the permanent magnets cancels the B0 inhomogeneity induced by ferromagnetic orthodontic appliances, resulting in drastic improvement of MR image quality.

47 11:45
Accelerated Imaging of Metallic Implants Using Model-Based Nonlinear Reconstruction
Xinwei Shi1,2, Evan G Levine1,2, and Brian A Hargreaves1,2

1Radiology, Stanford University, Stanford, CA, United States, 2Electrical Engineering, Stanford University, Stanford, CA, United States

3D Multi-Spectral Imaging (MSI) methods, including SEMAC, MAVRIC, and MAVRIC-SL, enable MRI near metallic implants by correcting for the metal-induced off-resonance artifacts, but their widespread application is limited by prolonged scan time. In this work, we introduce a novel model-based reconstruction method to accelerate 3D MSI. We demonstrate in phantom and in vivo experiments that the proposed method can accelerate MAVRIC-SL acquisitions by a factor of 4 when used alone, and 13-17 when combined with parallel imaging and half-Fourier acquisition. The images reconstructed by the proposed method showed sharper details and lower level of noise, compared with model-free L1-ESPIRiT. 

48 11:57
Bayesian correction of bias field and Venetian blind for high resolution ex vivo MRI with clinical scanners
Juan Eugenio Iglesias1, Pedro Manuel Paz-Alonso1, Garikoitz Lerma-Usabiaga1, Ricardo Insausti2, Karla Miller3, and César Caballero-Gaudes1

1Basque Center on Cognition, Brain and Language (BCBL), Donostia - San Sebastián, Spain, 2Human Neuroanatomy Laboratory, University of Castilla-La Mancha, Albacete, Spain, 3Centre for Functional MRI of the Brain, University of Oxford, Oxford, United Kingdom

Multi-slab MRI enables the acquisition of ultra-high resolution ex vivo MRI of the whole human brain with clinical scanners, by overcoming their hardware limitations (e.g., memory size). However, multi-slab MRI produces slab boundary artifacts (SBA) that degrade the image quality and bias subsequent image analyses. Here we propose a Bayesian method that corrects for SBA and intensity inhomogeneities / bias field (BF) simultaneously. The method, which combines a probabilistic brain atlas and the Expectation Maximization algorithm, takes advantage of the interplay between the two artifacts to outperform state-of-the-art SBA and BF correction algorithms (even when used in combination).

49 12:09
Breathing-induced B0 field fluctuations in the cervical spinal cord at 7T
Signe Johanna Vannesjo1, Falk Eippert1, Yazhuo Kong1, Stuart Clare1, Karla L Miller1, and Irene Tracey1

1FMRIB centre, NDCN, University of Oxford, Oxford, United Kingdom

Spinal cord MRI at ultra-high field poses considerable technical challenges, especially related to static and dynamic B0 field variations. We here investigated the magnitude and spatial profile of breathing-induced B0 field fluctuations in the cervical spinal cord at 7T, by comparing field maps acquired during breath-holds in an expired vs. inspired breathing state. Breathing-related field fluctuations of up to 140Hz at the level of C7 were observed. We further implemented a proof-of-principle shim correction, demonstrating the feasibility of using the shim system to compensate for the breathing-induced fields.

50 12:21
Robust Nyquist Ghost Correction by Incorporating Phase Errors Correction in SENSE
Victor B. Xie1,2, Mengye Lyu1,2, Yilong Liu1,2, Yangqiu Feng1,2, and Ed X. Wu1,2

1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China, People's Republic of, 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China, People's Republic of

In this abstract, we proposed a novel method that can fully and robustly correct EPI Nyquist ghost by incorporating high-order phase error correction into SENSE reconstruction. More importantly, this method does not induce SNR loss, greatly benefiting the final reconstructed images. Phantom and in vivo imaging results clearly demonstrated the efficacy of this method in ghost correct as well as its superior SNR performance, particularly in accelerated data set that can suffer from amplified noise problems. This novel method has great potentials to be applied in all kinds of EPI-based MRI studies, such as fMRI and DTI.

51 12:33
B0 Eddy Current Correction for Spiral MRI
Ryan K Robison1, Dinghui Wang1, Zhiqiang Li1, and James G Pipe1

1Imaging Research, Barrow Neurological Institute, Phoenix, AZ, United States

Eddy currents are a common source of artifacts in Spiral MRI. Eddy currents that effect the k-space trajectory are often the focus of eddy current correction. However, the spatially uniform but time-varying B0 eddy currents can also be a subtle but important source of artifacts in spiral images. This work demonstrates the improvement in image quality that can result from measuring and correcting the phase produced by B0 eddy currents in spiral MRI.


Oral

The Aging Brain

Hall 606 10:45 - 12:45 Moderators:Claudine Gauthier & Hanzhang LU

52 10:45
Reduced functional segregation between the default mode network and the executive control network in healthy older adults: a longitudinal study
Kwun Kei Ng1, June C. Lo1, Michael W.L. Chee1, and Juan Zhou1,2

1Duke-NUS Graduate Medical School, Singapore, Singapore, 2Clinical Imaging Research Centre, the Agency for Science, Technology and Research and National University of Singapore, Singapore, Singapore

The effects of age on functional connectivity (FC) of intrinsic connectivity networks (ICNs) have largely been derived from cross sectional studies. Far less is known about longitudinal changes in FC and how they relate to ageing-related cognitive decline. We found progressive loss of functional specialization with ageing evidenced by a decline in intra-network FC within the executive control (ECN) and default mode networks (DMN). In contrast, longitudinal change in FC between ECN and DMN followed a u-shaped trajectory whereby functional segregation between these two networks initially increased over time and later decreased as participants aged. The rate of loss in ECN-DMN functional segregation was associated with decline in processing speed.

53
10:57
Aging Effect on Creatine Kinase Enzyme Activity in Resting Human Brain: An In Vivo 31P-MT Study at 7T
Byeong-Yeul Lee1, Xiao-Hong Zhu1, and Wei Chen1

1Center for Magnetic Resonance Research, Radiology, University of Minnesota, Minneapolis, MN, United States

In this work, we investigated the aging effect on the enzyme activity of creatine kinase (CK) in healthy human visual cortex at resting state using a newly developed in vivo 31P magnetization transfer (31P-MT) method at 7T. Our results show that there was a strong aging dependence of the CK enzyme activity in the resting brain, implying a significant decline of brain energy metabolism in elderly people.  In vivo 31P-MT technique should provide a valuable tool for clinical research aiming to study aging-related neurodegenerative diseases such as Alzheimer’s disease, and potentially for other metabolic disorders/diseases. 

54
11:09
Cerebral venous oxygenation as a potential marker to differentiate normal aging from neurodegeneration
Zixuan Lin1, Marilyn Albert2, Peiying Liu3, Anja Soldan2, Abhay Moghekar3, Shin-Lei Peng4, Michael Miller1, Peter van Zijl3, and Hanzhang Lu3

1Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States, 2Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 3Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 4Department of Radiology, China Medical University, Taichung, Taiwan

Decreased cerebral venous oxygenation (Yv) has been considered as a compensation for aging which is diminished in neurodegeneration. We substantiated this hypothesis by examining the relationship between Yv and several Alzheimer-specific hallmarks on 65 normal elderly subjects. We demonstrated that Yv is higher in ApoE4 carriers who have increased risks of AD and that higher Yv is associated with poorer cognitive performance, indicating that assessment of Yv with non-invasive MRI methods may present a potential simple opportunity to identify the transition point from normal to pathological aging.

55 11:21
Hippocampal subfield diffusivity changes in healthy ageing
Daniel J Cox1,2, Hamied A Haroon2, Daniela Montaldi1, and Laura M Parkes2

1School of Psychological Sciences, University of Manchester, Manchester, United Kingdom, 2Centre for Imaging Sciences, University of Manchester, Manchester, United Kingdom

Alterations to hippocampal microstructure may precede gross volumetric changes in ageing, and these changes may occur preferentially in different hippocampal subfields. We investigated both established (FA and mADC) and novel (DOC) measurements of diffusion in these regions, in addition to volume, in order to determine where age-related changes occurred. The results showed changes across the majority of subfields for mADC and FA, but only in left CA 2/3 for DOC measures 1, 3 and >3. We suggest this could be related to differential degradation of particular cellular structures in these regions.

56 11:33
Early Shifts of Brain Metabolism by Caloric Restriction Preserve White Matter Integrity and Long-term Memory in Aging Mice
Janet Guo1, Ailing Lin1,2, and Vikas Bakshi1

1Department of Pharmacology & Nutritional Sciences, University of Kentucky, Lexington, KY, United States, 2Department of Biomedical Engineering, Lexington, KY, United States

Caloric restriction (CR) has been shown to increase healthspan in various species; however, its effects on preserving brain functions in aging remain largely unexplored. We used multimodal neuroimaging (PET/MRI/MRS) and behavioral testing to determine in vivo brain glucose metabolism, energy metabolites, and white matter structural integrity in young and old mice fed with either control or 40% CR diet. Blood glucose and ketone bodies were measured. Our findings suggest CR could slow brain aging, partly due to early shift of energy metabolism caused by lower caloric intake. These results provide rationale for CR-induced sustenance of brain health with extended longevity.  

57
11:45
Age-dependent changes in the BOLD Cerebrovascular Reactivity Curve in Response to Progressive Hypercapnia
Alex Bhogal1, Jill B de Vis1, Jeroen C.W. Siero1, Esben T Petersen2, Peter R. Luijten1, Jeroen Hendrikse1, Marielle E.P. Philippens3, and Hans Hoogduin4

1Radiology, UMC Utrecht, Utrecht, Netherlands, 2Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark, 3Radiotherapy, UMC Utrecht, Utrecht, Netherlands, 4Utrecht, Netherlands

Characterizing healthy, age-related changes in the BOLD-CVR response can provide a reference point from which to distinguish abnormal CVR from the otherwise normal effects of ageing. In this study, we examine age-dependent differences in grey and white matter BOLD-CVR response to progressive hypercapnia between young and elderly subjects. 

58
11:57
Assessment of cerebral response to exercise: effects of ageing and cardiorespiratory fitness
Andrew Hale1, Penny Gowland1, Paul Greenhaff2, and Susan Francis1

1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, 2Faculty of Medicine & Health Sciences, Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom

Although there is a general relationship between age and brain function, habitual physical activity levels may also impact on brain health. We performed a MR study involving low and moderate intensity supine exercise in healthy young and older subjects. We assess the effect of exercise on CBF response in large arteries, regional perfusion and BOLD, and the relationship of grey matter volume with physical fitness and ageing. On exercise there was a clear CBF, perfusion and BOLD response to exercise in young volunteers, whilst a reduced CBF, perfusion and BOLD response to exercise was found in the older volunteers.

59 12:09
Consistent detection of age-dependent variations of the longitudinal relaxation time in cortical brain regions investigated by MP2RAGE at 9.4T: influence of correcting for a non-uniform transmit field
Gisela E Hagberg1,2, Jonas Bause1, Thomas Ethofer2,3, Philipp Ehses1, Thomas Dresler3, G Shajan1, Rolf Pohmann1, Cornelia Herbert3, Andreas Fallgatter3, Christoph Laske3, Marina Pavlova2, and Klaus Scheffler1,2

1High Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 2Biomedical Magnetic Resonance, University Hospital Tübingen, Tübingen, Germany, 3General Psychiatry&Psychotherapy, University Hospital Tübingen, Tübingen, Germany

Accurate and precise determination of T1 values is of central importance in clinical studies and for tissue segmentation based on the myeloarchitecture that transcends T1. Here we investigate whether well-described age-dependent changes can be detected by high field T1 relaxometry, and how different transmit field correction methods influence the results. We found that the intrinsic bias correction of the MP2RAGE technique is not sufficient to achieve reliable quantification of T1 at ultra high magnetic fields. But, provided that a correction for transmit field inhomogeneity is performed, T1 maps that consistently reveal age-related changes can be generated. The technique holds promise for investigation of local myeloarchitectonics for neuroscientific and clinical studies.

60
12:21
Changes in white matter structural connectivity and cortical functional connectivity over the healthy adult lifespan
Adrian Tsang1,2,3, Catherine Lebel1,4, Signe Bray1,4, Brad Goodyear1,2,3, Roberto C. Sotero1, Cheryl McCreary1,3, and Richard Frayne1,2,3

1Department of Radiology, University of Calgary, Calgary, AB, Canada, 2Hotchkiss Brain Institute, Calgary, AB, Canada, 3Seaman Family MR Research Centre, Calgary, AB, Canada, 4Child and Adolescent Imaging Research Program, Alberta Children's Hospital Research Institute, Calgary, AB, Canada

This study investigates how both structural and functional connectivity (SC and FC) changes in the adult lifespan as well as to explore the relationship between measures that are commonly used for SC and FC in the context of normal aging. A multi-modal analysis using DTI and resting-state fMRI data was performed from 183 healthy participants aged 18 – 87 years. We found that fractional anisotropy (FA) and FC showed similar rate of change and correlation strengths with age in the 7 resting-state networks explored. However none of the SC measures showed significant correlations with FC measure. 

61 12:33
Diagnostic accuracy of MRS for Hereditary Neurodegeneration at 3T and 7T
Uzay E Emir1,2, Tianmeng Lyu3, Dinesh K Deelchand2, James M Joers2, Diane Hutter2, Christopher M Gomez4, Khalaf O Bushara5, Lynn E Eberly3, and Gulin Oz2

1FMRIB Centre, University of Oxford, Oxford, United Kingdom, 2Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States, 3Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States, 4Department of Neurology, University of Chicago, Chicago, IL, United States, 5Department of Neurology, Medical School, University of Minnesota, Minneapolis, MN, United States

To evaluate diagnostic accuracy of state-of-the-art MRS in early neurodegenerative disease, we measured neurochemical profiles in the vermis, cerebellar hemisphere and brainstem of genetically confirmed subjects with spinocerebellar ataxia type 1 and controls by 3T and 7T 1H MRS. Concentrations of major metabolites obtained at 3T and 7T were strongly correlated. While 3T showed great potential by enabling detection of abnormal metabolite levels even in the presymptomatic stage, the increased sensitivity at 7T enabled group separation with higher significance and identification of subtle neurochemical alterations in early symptomatic disease stage more robustly than at 3T. 


Oral

fMRI Analysis: Post-Processing

Summit 1 10:45 - 12:45 Moderators:José Marques & R. Allen Waggoner

62
10:45
Nuisance Regression of High-frequency FMRI Data: De-noising Can Be Noisy
Jingyuan E. Chen1,2, Hesamoddin Jahanian2, and Gary H. Glover1,2

1Electrical Engineering, Stanford University, Stanford, CA, United States, 2Radiology, Stanford University, Stanford, CA, United States

A growing number of studies using fast sampling have demonstrated the persistence of functional connectivity (FC) in resting state (RS) networks beyond the conventional 0.1 Hz. However, some RS studies have reported frequencies (e.g., up to 5 Hz) not easily supported by canonical hemodynamic response functions. Here, we investigated the influence of a common preprocessing step – whole-band (the entire frequency band resolved by a short TR) linear nuisance regression (LNR) – on RSFC. We demonstrated via both simulation and real data that LNR can introduce network structures in HF bands, which may largely account for the observations of HF-RSFC.

63
10:57
A family-constrained local canonical correlation model to improve activation detection in fMRI
Xiaowei Zhuang1, Zhengshi Yang1, Tim Curran2, and Dietmar Cordes1,2

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

A family constrained CCA (cCCA) method was introduced to improve the accuracy of activation detection in noisy fMRI data. The cCCA was converted into a constrained multivariate multiple regression problem and solved efficiently with a numerical optimization algorithm. Results from both simulated data and real episodic memory data indicated that a higher detection sensitivity for a fixed specificity can be achieved with the proposed cCCA method as compared to the widely used mass-univariate or other conventional multivariate (CCA) approaches.

64
11:09
Use of T2-weighted 3D acquisition  for correction of EPI-induced distortion in fMRI
Andrea Nordio1,2,3, Denis Peruzzo2, Filippo Arrigoni2, Fabio Triulzi2,4, and Alessandra Bertoldo1,2

1Department of Information Engineering (DEI), University of Padova, Padova, Italy, 2IRCCS E.Medea, Bosisio Parini, Lecco, Italy, 3IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy, 4IRCCS Cà Granda Ospedale Maggiore, Policlinico, Milano, Italy

Echo Planar Imaging (EPI) sequences used for acquiring fMRI time series data have a high temporal resolution but are also highly sensitive to the magnetic field inhomogeneity resulting in geometric distortions. In this work we propose an approach for correction of EPI distortion in fMRI sequences.  Our method takes advantage of a non-distorted T2-weighted (T2W) 3D sequence as intermediate step between the acquired fMRI data and the anatomical image. This strategy allows to use non-linear registration functions. We validated our method on a group of healty subjects during finger-tapping task, proving that the proposed method significantly improves the group analysis results of functional data.

65
11:21
Investigating the effects of venous vasculature on the BOLD response: A combined SWI and multi-band fMRI approach
David Provencher1, Alexandre Bizeau1, Yves Bérubé-Lauzière2, and Kevin Whittingstall1,3

1Radiation Sciences and Biomedical Imaging, Université de Sherbrooke, Sherbrooke, QC, Canada, 2Electrical and Computer Engineering, Université de Sherbrooke, Sherbrooke, QC, Canada, 3Diagnostic Radiology, Université de Sherbrooke, Sherbrooke, QC, Canada

We previously showed that venous density correlates with BOLD signal amplitude1. Since the BOLD contrast inherently originates in veins, we hypothesized that its temporal dynamics would also be affected by venous density. Here, we use fast multi-band fMRI imaging (TR=0.45s), SWIp vein reconstruction and different visual stimuli yielding co-localized activation, yet different BOLD dynamics. From this, we assess the effects of venous density on BOLD timing. Results show a robust association between higher vein density and shorter hemodynamic delay when comparing activated and deactivated regions. BOLD response timing differences may thus not entirely reflect neural activity, but also structural differences.

66
11:33
The hidden heart rate in the slice-wise BOLD-fMRI global signal.
Michael Hütel1,2, Andrew Melbourne1, David L Thomas1,2, Jonathan Rohrer2, and Sebastien Ourselin1,2

1Translational Imaging Group, University College London, London, United Kingdom, 2Dementia Research Centre, University College London, London, United Kingdom

Previous studies have shown that slow variations in the cardiac cycle are coupled with signal changes in the blood-oxygen level dependent (BOLD) contrast. The detection of neurophysiological hemodynamic changes, driven by neuronal activity, is hampered by such physiological noise. It is therefore of great importance to model and remove these physiological artefacts. The cardiac cycle causes pulsatile arterial blood flow. This pulsation is translated into brain tissue and fluids bounded by the cranial cavity. We exploit this pulsality effect and provide evidence that the heart rate is inherent in BOLD fMRI images.

67
11:45
Advanced combinations of dual-echo fMRI data provide no advantages over the simple average at group-level analyses
Ádám Kettinger1,2, Christian Windischberger3, Christopher Hill4, and Zoltán Nagy4

1Department of Nuclear Techniques, Budapest University of Technology and Economics, Budapest, Hungary, 2Brain Imaging Centre, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary, 3Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria, 4Laboratory for Social and Neural Systems Research, University of Zurich, Zurich, Switzerland

Multi-echo EPI acquisitions are used in fMRI research due to their superior BOLD sensitivity. Several advanced methods of echo combinations have been proposed. We confirmed, using dual-echo data, that CNR weighting is the optimal combination on a single subject level. However, we have shown that these advantages do not carry over to a group analysis where a simple averaging of the echos provides equally good statistical results. This is likely due to the increase of inter-subject variance of contrast-to-noise ratio. Future work aims to quantitatively compare inter-subject and intra-subject variance of dual-echo data in group studies.

68 11:57
Effect of temporal resolution and serial autocorrelations in fast fMRI
Ashish Kaul Sahib1, Klaus Mathiak2, Michael Erb1, Adham Elshahabi3, Silke Klamer3, Klaus Scheffler4, Niels Focke3, and Thomas Ethofer1

1Biomedical magnetic resonance, University of tuebingen, Tuebingen, Germany, 25Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital Aachen, Aachen, Germany, 3Department of Neurology/Epileptology, University of tuebingen, Tuebingen, Germany, 4Max-Planck-Institute for Biological Cybernetics, Tuebingen, Germany

To assess the impact of colored noise on statistics and determine optimal imaging parameters in event-related fMRI (visual stimulation using checkerboards) acquired by simultaneous multi-slice imaging enabling repetition times (TR) between 2.64 to 0.26s. Optimal statistical power was obtained for a TR of 0.33s, but short TRs required higher-order autoregressive (AR) models to achieve stable statistics.  Colored noise in event-related fMRI obtained at short TRs calls for more sophisticated correction of serial autocorrelations.

69
12:09
Individual Subject Functional Connectivity Parcellation with Group-Level Spatial and Connectivity Priors
Ru Kong1, Alexander Schaefer1, Avram J. Holmes2, Simon B. Eickhoff3,4, Xi-Nian Zuo5, and B.T. Thomas Yeo1

1Department of Electrical and Computer Engineering, ASTAR-NUS Clinical Imaging Research Centre, Singapore Institute for Neurotechnology and Memory Networks Program, National University of Singapore, Singapore, Singapore, 2Department of Psychology, Yale University, New Haven, CT, United States, 3Institute for Clinical Neuroscience and Medical Psychology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany, 4Institute for Neuroscience and Medicine (INM-1), Research Center Jülich, Jülich, Germany, 5Lab for Functional Connectome and Development Division of Cognitive and Developmental Psychology, CAS, Beijing, China, People's Republic of

We propose a hidden Markov Random Field (MRF) model to parcellate the cerebral cortex of individual subjects using resting-state fMRI (rs-fMRI). Our MRF model imposes a smoothness prior on the individual-specific parcellation, while imposing group-level population priors that capture inter-subject variability in both functional connectivity profiles and spatial distribution of functional brain networks. Experiments on a test-retest dataset suggest that the resulting parcellation estimates are better than alternative approaches at capturing stable properties of individual subjects’ intrinsic brain organization, instead of transient noise or session-dependent variations.

70 12:21
High-resolution T1-mapping using inversion-recovery EPI and application to cortical depth-dependent fMRI at 7 Tesla
Sriranga Kashyap1, Dimo Ivanov1, Martin Havlíček1, Benedikt A Poser1, and Kâmil Uludağ1

1Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands

Cortical-depth dependent fMRI usually relies on the definition of depths on an anatomical image (eg. MPRAGE). The geometric dissimilarities of the functional compared to the anatomical data require further spatial processing of the functional data to ensure good co-registration. We propose an alternative approach that uses an optimised inversion-recovery EPI derived T1 image, whose resolution and readout, hence distortions, are identical to that of the functional data, in order to delineate cortical depths. As a result, the cortical-depth specific fMRI data can be analysed in the native space without any spatial confounds stemming from distortion correction and inaccurate registration.

71 12:33
Distortion-matched T1-maps and bias-corrected T1w-images as anatomical reference for submillimeter-resolution fMRI
Wietske van der Zwaag1, Pieter Buur1, Maarten Versluis2, and José P. Marques3

1Spinoza Centre for Neuroimaging, Amsterdam, Netherlands, 2Philips Healthcare, Best, Netherlands, 3Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands

Achieving sufficiently good quality co-registration between the anatomical and functional images is currently a large stumbling block for laminar fMRI. Here, we present a distortion-matched T1weighted/T1-estimation mapping approach using two 3D-EPI readouts per inversion, following the MP2RAGE signal combination. 0.7mm isotropic T1 data with matching distortions to a 0.7mm isotropic fMRI protocol can be acquired in less than two minutes.


Oral

Imaging of Joint Health & Disease

Summit 2 10:45 - 12:45 Moderators:Emily McWalter & Edwin Oei

72 10:45
Imaging Cartilage-Bone Interactions in Osteoarthritis using Simultaneous 18F-NaF PET-MR imaging– the “Bone-Cartilage Connectome”
Dragana Savic1,2, Valentina Pedoia1, Youngho Seo1, Matthew Bucknor1, Benjamin Franc1, and Sharmila Majumdar1

1University of California San Francisco, San Francisco, CA, United States, 2University of Oxford, Oxford, United Kingdom

This first in human study evaluated cartilage biochemistry and bone function in sixteen knee osteoarthritis patients using simultaneous Time-Of-Flight (TOF) PET/MR imaging.  Bone turnover and blood flow was studied using 18F Sodium Fluoride (NaF) and quantitative voxel by voxel MR derived T relaxation times characterizing the biochemical cartilage degeneration. Increased degeneration of cartilage, was associated with increased turnover in the adjoining bone as well as in the non-adjoining compartments. These observations highlight the complex biomechanical and biochemical interactions in the whole knee joint, alluding to a “bone-cartilage connectome”, that potentially changes during the natural history of the disease. 


73
10:57
Dynamic analysis of [18F]-sodium fluoride uptake in knee osteoarthritis with PET-MRI
Audrey P Fan1, Feliks Kogan1, Aleema Patel1, Edwin HG Oei2, Andrew Quon1, and Garry E Gold1

1Radiology, Stanford University, Stanford, CA, United States, 2Erasmus MC: University Medical Center Rotterdam, Rotterdam, Netherlands

This study investigates dynamic uptake of [18F]-fluoride in bone marrow lesions (BMLs) and osteophytes observed on MRI of patients with knee osteoarthritis. Through kinetic modeling, we characterized rate constants of bone metabolism in bone pathology relative to healthy bone. BMLs and higher-grade osteophytes showed higher total bone metabolism Ki (P < 0.01) and higher bone mineralization rate k3 (P < 0.01) relative to grade 1 osteophytes and normal bone. While a similar trend was observed for blood flow, the differences from normal tissue were subtler suggests that rate of mineralization k3 and not blood flow is a key driver of [18F]-fluoride accumulation in OA lesions. These new physiological parameters may help differentiate between different grades of OA lesions or identify which lesions are active parts of the disease process.

74 11:09
Longitudinal Evaluation of Cartilage Component of Matrix-Associated Autologous Chondrocyte Transplants using Biochemical MR Imaging
Xian Xu1, Ningyu An1, Panli Zuo2, and Esther Raithel3

1Department of Radiology, Chinese PLA General Hospital, Beijing, China, People's Republic of, 2Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, People's Republic of, 3Siemens Healthcare GmbH, Berlin, Germany

This study combined T2 mapping and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) technique to evaluate the repair cartilage tissue after Matrix-associated autologous chondrocyte implantation (MACI). We found that the T2 and ΔR1 values of the repair tissue were significantly higher than the native tissue at 1, 3 and 6 months after MACI, but showed a downward trend and showed no difference with native tissue at 12 months, which suggested that the integrity of the collagen and GAG of repair tissue was similar to native cartilage. 

75 11:21
Loaded MRI – A Surrogate Measurement of in vivo Knee Joint Contact Mechanics
Matthew F. Koff1, Hongsheng Wang2, Suzanne Maher2, Scott Rodeo3, and Hollis G Potter1

1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, NY, United States, 2Department of Biomechanics, Hospital for Special Surgery, New York, NY, United States, 3Sports Medicine and Shoulder Service, Hospital for Special Surgery, New York, NY, United States

The relationship between calculated articular cartilage deformation when using an MR compatible loading device and actual contact mechanics has not been assessed. This study evaluated the accuracy of in vivo cartilage deformation as a surrogate for in vivo contact mechanics. Meniscal allograft transplantation patients underwent loaded MR pre-operatively and direct stress measurement intra-operatively. Good correlation, 0.72 (range: 0.56 to 0.85), between cartilage deformation and contact stress measurements was found. In vivo cartilage deformation may be a surrogate for in vivo contact mechanics.

76 11:33
Incorporation of Finite Pulse Correction for Improved MT-Corrected Multicomponent T2 analysis of Cartilage
Fang Liu1, Alexey Samsonov1, Wally Block2, and Richard Kijowski1

1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, United States

Nuclear magnetic resonance studies have identified multiple water components within cartilage tissue. Previous studies using steady-state sequences based rapid method such as mcDESPOT and mcRISE have shown feasibility of multicomponent T2 analysis of cartilage. However, steady-state signal can be influenced by the finite pulse effect which might lead to biased parameter estimation. In this study, we incorporated the finite pulse correction in the mcRISE model and demonstrated the potential MT and finite pulse effect in-sensitive T2 parameters for multicomponent cartilage relaxometry analysis.

77 11:45
Correlation of MRI Appearance of Total Hip Arthroplasty With Wear Metric and Histologic Evaluation
Matthew F. Koff1, Parina H. Shah1, Mauro Miranda1, Christina Esposito2, Elexis Baral2, Kara Fields3, Thomas Bauer4, HSS Adult Reconstruction & Joint Replacement Division5, Douglass Padgett5, Timothy Wright2, and Hollis G. Potter1

1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, NY, United States, 2Department of Biomechanics, Hospital for Special Surgery, New York, NY, United States, 3Healthcare Research Institute, Hospital for Special Surgery, New York, NY, United States, 4Cleveland Clinic Foundation, Cleveland, OH, United States, 5Adult Reconstruction and Joint Replacement Division, Hospital for Special Surgery, New York, NY, United States

A majority of primary total hip arthroplasty (THA) function well but implant failure may occur. We propose MRI to evaluate adverse local tissue reactions (ALTRs) in patients with THA. In this study, we correlate indirect measures of ALTRs with direct measurements of implant wear. Greater volumetric wear and visual damage was found in subjects with ALTR on MR images. MR also correlated with histologic metrics of implant wear. The results indicate that MRI allows for accurate diagnosis of different synovial patterns in THA, which correlate to wear analysis at retrieval.

78 11:57
In Vivo Evaluation of Low-grade Cartilage Defects in the Knee using Sodium MRI at 7T
Stefan Zbyn1,2, Vladimir Mlynarik1, Vladimir Juras1, Markus Schreiner1,3, Didier Laurent4, Joerg Goldhahn4, Nicole Getzmann4, Stefan Marlovits5, and Siegfried Trattnig1

1Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria, 2CD Laboratory for Clinical Molecular MR Imaging, Vienna, Austria, 3Department of Orthopaedics, Medical University Vienna, Vienna, Austria, 4Novartis Institutes for Biomedical Research, Basel, Switzerland, 5Department of Trauma Surgery, Medical University Vienna, Vienna, Austria

To our best knowledge, this is the first report on employing sodium (23Na) MRI for the in vivo evaluation of low-grade cartilage defects in the knee joint. In this 7T study, regions with chondral defect, weight-bearing, and non-weight-bearing femoral cartilage were evaluated in 23Na-images of patients after knee injury. Test-retest comparison showed high robustness and repeatability of sodium data. 23Na-MRI allowed differentiation between normal-appearing cartilage and low-grade chondral defects. 23Na-MRI can be used for noninvasive follow-up of changes in GAG content associated with cartilage degeneration. This method might be particularly useful for the evaluation of cartilage regenerating therapies.

79 12:09
Local Analysis of T1ρ, T2, and R2–R1ρ Compositional MR Imaging in Patients with ACL Injury Using Voxel-Based Relaxometry
Colin Russell1, Valentina Pedoia1, Keiko Amano1, and Sharmila Majumdar1

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

This multicenter study employs VBR as a novel technique to analyze patients with ACL tears at the time of injury and 6 months after ACL reconstruction. T and T2 analysis, correlation, and dispersion difference (R2–R) are three methods employed to highlight significant cartilage changes. The most posterior region of the posterior lateral tibia and the patella indicated partial cartilage recovery 6 months after reconstruction, demonstrated by decreasing T and T2, decreased T T2 correlation baseline to 6 months, and dispersion differences (R2–R). The trochlea displayed symptoms of cartilage degeneration, such as elevated T and T2 and dispersion differences.

80 12:21
In vivo assessment of T2* in menisci under loading conditions at 3 Tesla: preliminary results
Vladimir Juras1,2, Lenka Hornakova3, Petr Kubovy3, Daniel Hadraba3,4, Pavel Stursa5, David Gerych3, Pavol Szomolanyi1, Karel Jelen3, and Siegfried Trattnig1,6

1Department of Biomedical Imaging and Image-Guided Therapy, High Field MR Centre, Medical University of Vienna, Vienna, Austria, 2Department of Imaging Methods, Institute for Measurement Science, Bratislava, Slovakia, 3Department of Anatomy and Biomechanics, Faculty Of Physical Education and Sport, Prague, Czech Republic, 4Department of Radiology, Hospital na Homolce, Prague, Czech Republic, 5Academy of Sciences of the Czech Republic, Prague, Czech Republic, 6Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria

Meniscus behavior under loading in vivo has been studied using parametric MR imaging. T2* has been acquired with vTE using very short first TE = 0.8 ms to secure the precise estimation. The knees of the subjects were loaded in situ with custom made compression device and T2* mapping was performed in 5 time points (without loading, and 4 consequent scans under the loading 7 min apart). The increase in T2* was observed in all compartments, significance was found in medial meniscus only. vTE T2* mapping might be a prospective marker for detecting the dynamic response of the meniscal tissue. 

81 12:33
3D UTE Cones-IDEAL Imaging of the Knee and Ankle joints: Fast Volumetric Imaging with Robust Fat/water Separation
Qun He1,2, Michael Carl3, Graeme Bydder1, and Jiang Du1

1University of California, San Diego, San Diego, CA, United States, 2Ningbo Jansen NMR Technology Co., Ltd., Cixi, Zhejiang, China, People's Republic of, 3Global MR Applications & Workflow, General Electric, San Diego, CA, United States

UTE sequences combined with IDEAL processing produces high contrast images of short T2 tissues or tissue components such as menisci, ligaments, and tendons. In this work, we report the use of 3D UTE Cones imaging and IDEAL processing (3D Cones-IDEAL) for volumetric imaging of short T2 tissues in the knee and ankle joints at 3T. High resolution volumetric imaging of the knee and ankle joints, together with robust fat/water separation, field map estimation, R2*/T2* mapping and fat fraction mapping are demonstrated.


Educational Course

Body MRI Applications in the Emergency Department

Organizers:Lorenzo Mannelli, M.D., Ph.D., Ivan Pedrosa, M.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Nicoll 1 10:45 - 12:45 Moderators:Yu-Ting Kuo & Jing Yuan

10:45
Rapid MRI Protocols & Acquisitions for Emergency Patients
Jennifer Uyeda


11:15
MRI in Acute Appendicitis: The Emergency Physician Perspective
Michael D Repplinger1

1Emergency Medicine, University of Wisconsin - Madison, Madison, WI, United States

In this presentation, we will discuss the diagnostic accuracy of MR to diagnose appendicitis, both in the general population and in select cohorts. Additionally, we will discuss the evidence for various MR sequences (unenhanced, intravenous contrast-enhanced, and DWI) as well as the affect of radiologist expertise in abdominal MR on diagnostic accuracy. Finally, we will discuss how using MR in the emergency department setting impacts patient care, particularly their timely evaluation.

11:45
Pulmonary MRA
Jeffrey H. Maki1

1Radiology, University of Washington, Seattle, WA, United States

Accurately diagnosing pulmonary embolism is clinically vital, with CT Pulmonary Angiography (CTPA) the most often used diagnostic tool.  CTPA, however, is not without limitations.  The largest of these is ionizing radiation, which for younger patients can significantly increase lifetime attributable cancer mortality risk, especially considering a positive CTPA rate of <10%.   Additionally, many patients have iodine allergies or are pregnant.  Pulmonary MRA is an emerging technology that has benefited from new technical advances and recently proven to have a high negative predictive value similar to CTPA. Pulmonary MRA should be considered in the young and those where CTPA is contraindicated.

12:15
MRV
Charles Kim1

1Radiology, Duke University Medical Center, Durham, NC, United States

MR venography can play a vital role in the diagnosis and treatment planning for acute venous thrombosis if well-developed protocols and referral patterns are in place. The two primary emergency indications for MR venography will be discussed in detail: acute iliofemoral / lower extremity DVT  and acute SVC syndrome. The ideal MR venography contrast agents will be reviewed, as well as optimized MR venography protocols. This lecture will provide the audience with pertinent clinical information, pros and cons of various competing imaging modalities, and emphasize key reporting topics for these various pathologies.

12:45
Adjournment & Meet the Teachers


Combined Educational & Scientific Session

Molecular Imaging of Inflammation & Infection

Organizers:Natalie J. Serkova, Ph.D.

Nicoll 2 10:45 - 12:45 Moderators:Francesca Branzoli & Natalie Serkova

10:45
Assessing CNS Vasculature and inflammation using dual GBCA and ferumoxytol-enhanced MRI
Edward Neuwelt

            Ferumoxytol as an MRI contrast can provide additional information on CNS lesions. Pre-clinical studies have used advanced neuroimaging techniques with ferumoxytol to evaluate tumor changes after different treatments in animal models as well as evaluation of acute neuroinflammation. Clinically, ferumoxytol has been used to differentiate tumor progression from pseudoprogression and also to evaluate inflammatory and vascular CNS lesions.  Dual-contrast imaging may mark the beginning of a multicontrast era when different contrast agents are applied for specific purposes to evaluate CNS lesions. Improved neuroimaging can potentially be incorporated into standard of care for assessing therapy-induced changes and tumor response to therapy.

82 11:15
Radiation-induced inflammatory response in tumor-bearing immune-compromised mice by SPIO-enhanced T2-MRI
Natalie Julie Serkova1, Kendra M Huber1, Barbara Frederick2, Elizabeth R Kessler3, Thomas W Flaig3, and Brian D Kabanagh2

1Anesthesiology, University of Colorado Denver, Aurora, CO, United States, 2Radiation Oncology, University of Colorado Denver, Aurora, CO, United States, 3Medical Oncology, University of Colorado Denver, Aurora, CO, United States

Clinically, the radiation treatment (RT) is know to trigger an inflammatory response which can be beneficial for overall anti-cancer treatment efficacy. However, in pre-clinical mouse models, the tumor response to the RT is rather heterogenous. Our hypothesis is that tumor-associated macrophages which drive the pro-inflammatory response to the RT, are expressed differently in various mouse strains based on their genetic make-up. The goal of this study was to non-invasively assess the tumor inflammatory response to the RT based on iron oxide-induced changes in T2-MRI after injection of SPIO nanoparticles in two different mouse models with severely (NOD SCID) and moderately (nu/nu athymic) compromised immune system.

83 11:27
Neuroimaging of Nipah Virus in a Syrian Hamster Model of Infection
Margaret R. Lentz1, Dima A. Hammoud2, Yu Cong1, Oscar Rojas1, David Thomasson1, Peter B. Jahrling1,3, and Michael R. Holbrook1

1Integrated Research Facility, NIAID, National Institutes of Health, Frederick, MD, United States, 2Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States, 3Emerging Viral Pathogens Section, NIAID, National Insitutes of Health, Frederick, MD, United States

The purpose of this study was to utilize MRI  to assess alterations in the brain that occur in a Golden Syrian hamster infected with Nipah virus (NiV) via intranasal inoculation. Within 9 days of exposure to NiV, signal alterations were observed in the olfactory bulb in T2-weighted and FLAIR images, suggestive of inflammation and edema induced by NiV crossing the olfactory epithelium. The identification of non-invasive imaging biomarkers of acute NiV neurologic disease progression in this animal model could aid in the examination of potential vaccines and therapeutics.

11:39
Novel Imaging Tracers for Rapid and Noninvasive Assessment of Bacterial Infections
Sanjay Jain1

1Johns Hopkins Medical Institute

We are developing novel imaging tracers for rapid and noninvasive assessment of bacterial infections and to study antimicrobial pharmacokinetics.

84 12:09
Diffusion and perfusion MR imaging indicate inflammation followed by fibrosis in a hepatitis B infected humanized mouse liver model
Prashant Chandrasekharan1, Dahai Zheng2, Kavita Kaur D/O Ranjit Singh1, Qingfeng Chen2, and Kai Hsiang Chuang1

1A*STAR, Singapore Bio Imaging Consortium, Singapore, Singapore, 2A*STAR, Institute of Molecular and Cell Biology, Singapore, Singapore

Humanized mouse model of liver infection is essential to understand the role of the immune system during disease progression and therapeutic intervention. In this study we have used MRI functional imaging bio-markers to assess the pathology related to Hepatitis B infection in a humanized mouse liver model.

85 12:21
Identifying carotid plaque inflammation using high and low molecular weight contrast agents
Jason Kraig Mendes1, Scott McNally1, Seong-Eun Kim1, Bradley D. Bolster2, Gerald S. Treiman3, and Dennis L. Parker1

1Radiology, University of Utah, SLC, UT, United States, 2Siemens Healthcare, SLC, UT, United States, 3Department of Veterans Affairs, SLC, UT, United States

Carotid plaque inflammation can be measured with dynamic contrast enhanced (DCE) MRI and is a marker for plaque instability. Despite this, DCE has not become a clinically viable tool in diagnosing carotid plaque instability and the corresponding stroke risk. The barrier to progress is a DCE protocol meeting requirements for clinical use to monitor medical treatment effect or failure. This project overcomes this barrier by developing a reliable and inclusive dual contrast DCE protocol to identify carotid plaque inflammation.

12:33
Panel Discussion

12:45
Adjournment & Meet the Teachers


Combined Educational & Scientific Session

Proving Where MRI has Value

Organizers:Garry E. Gold, M.D. & James G. Pipe, Ph.D.

Nicoll 3 10:45 - 12:45 Moderators:Daniel Sodickson & Garry Gold

10:45
What Makes for a Clinically Useful MR Exam?
Scott Reeder1

1University of Wisconsin, Madison, WI, United States

Development, validation, and translation of advanced new imaging methods is an exciting and important area of scientific development and clinical medicine. The development of standardized approaches and objective measures of new imaging technologies such as SNR and CNR, and subjective ordinal metrics are extremely helpful particularly in the early stages of technical development and translation. Subsequent studies comparing new imaging techniques with accepted reference standards, is the next step to establish the diagnostic performance of a technique for the detection and staging of disease.  Ultimately, clinical effectiveness and patient outcomes are the most important metric of the impact of new technologies.  Finally, there are many practical barriers that should be considered, including work flow, post-processing, that are needed to garner acceptance by technologists, radiologists, and referring physicians.

11:10
From k-Space to Pasteur’s Quadrant: Your Research Can Make the World a Better Place
Richard L Ehman1

1Radiology, Mayo Clinic, Rochester, MN, United States

The ISMRM has launched the “MR Value Initiative”, to encourage innovative optimization the value of MR-based diagnostic technologies.  Both the numerator (clinical benefit) and the denominator (cost) of the value ratio can be targeted by scientific and technical innovation.  Studies have shown that investigators in medical imaging generate innovations at a high rate, and that these inventions can often be readily translated, with extraordinary impact on patient care.  This presentation focuses on identifying time-tested strategies that aspiring innovators can use to improve the chances that their work will have an impact and perhaps make the world a better place.

11:35
Panel Discussion

86 11:45
Reperfusion beyond 6 hours impacts Tissue Fate of Moderate Ischemia
Hongyu An1, Andria L Ford2, Cihat Eldeniz1, Yasheng Chen2, Katie D Vo3, Hongtu Zhu4, William J Powers5, Weili Lin6, and Jin-Moo Lee2

1Washington University in St. Louis, St. Louis, MO, United States, 2Neurology, Washington University in St. Louis, St. Louis, MO, United States, 3Radiology, Washington University in St. Louis, St. Louis, MO, United States, 4Biostatistics, University of North Carolina At Chapel Hill, Chapel Hill, NC, United States, 5Neurology, University of North Carolina At Chapel Hill, Chapel Hill, NC, United States, 6Radiology, University of North Carolina At Chapel Hill, Chapel Hill, NC, United States

The fate of mild to moderate ischemic tissue is greatly impacted by both hyperacute (3-6 hr)  and acute (6-24hr) perfusion changes. Thus, such regions could be targeted for intervention beyond current treatment windows. 

87
11:57
Cost Effectiveness of MRI Before Prostate Biopsy
Shivani Pahwa1, Nicholas Schiltz2, Lee Ponsky3, Ziang Lu1, Sara Dastmalchian1, Robert Abouassaly3, Mark Griswold4, and Vikas Gulani5

1Radiology, Case Western Reserve University, Cleveland, OH, United States, 2Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH, United States, 3Urology, Case Western Reserve University, Cleveland, OH, United States, 4Radiology and Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, 5Radiology, University Hospitals Case Medical Center, Cleveland, OH, United States

The perception that MRI inflates health care costs impedes its incorporation into prostate cancer treatment algorithms, despite robust evidence of its accuracy. We evaluated the cost effectiveness of 13 different strategies using a decision tree model in which MRI is performed before non-targeted, transrectal ultrasound guided prostate (TRUS) biopsy. Our results show that MRI is cost effective in each of these strategies, and also adds incremental quality adjusted life years (QALY) to the patient over and above the standard practice of performing non-targeted TRUS biopsy. 

88 12:09
Progress towards Robust Spiral MRI for Rapid Brain Exams
James Grant Pipe1, Ashley Gould Anderson1, Akshay Bakhru2, Zhiqiang Li1, Suthambhara Nagaraj2, Melvyn B Ooi3, Ryan K Robison1, Dinghui Wang1, and Nicholas R Zwart1

1Imaging Research, Barrow Neurological Institute, Phoenix, AZ, United States, 2MRI, Philips Healthcare, Bangalore, India, 3MRI, Philips Healthcare, Phoenix, AZ, United States

This work gives an overview of an effort to build the infrastructure for rapid, robust clinical Spiral MRI of the brain.  The current goal is to achieve comparable or better Image quality than conventional scans with reduced overall scan time.  A long-term (future) goal is to achieve a comprehensive high-quality brain MR exam in 5 minutes.

89 12:21
The value of MRI in Traumatic Brain Injury: experiences in the Collaborative European NeuroTrauma Effectiveness Research in TBI study
Pim Pullens1, Andrew IR Maas2, David Menon3, Wim van Hecke4, Jan Verheyden4, Lene Claes4, Paul M Parizel1, and On behalf of CENTER-TBI participants and investigators5

1Radiology, Antwerp University Hospital & University of Antwerp, Antwerp, Belgium, 2Neurosurgery, Antwerp University Hospital & University of Antwerp, Antwerp, Belgium, 3Anaesthesia, University of Cambridge, Cambridge, United Kingdom, 4icometrix NV, Leuven, Belgium, 5University Hospital Antwerp, Antwerp, Belgium

Traumatic Brain Injury (TBI) is regarded as “the most complex disease in our most complex organ”. Clinical outcome is unpredictable, especially in repetitive mild TBI, in terms of behavior, cognition, emotion and associated long-term effects such as dementia. The Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI) study is a pan-European prospective longitudinal observational study aiming to improve care for TBI patients. One of the key goals is to improve the quality of imaging-derived data by the application of a clinical standardized MR imaging protocol including structural, SWI, DTI and rs-fMRI, across up to 25 clinical sites in a large, heterogeneous sample of TBI patients. Harmonization of these protocols has been a challenging task. As data collection is underway, 265 datasets have been inspected for quality. Data quality is variable across sites and scanners. In order for such large-scale observational studies to be really effective, sequence harmonization and standardization is of key importance, but lacking at the moment.

90 12:33
Capturing clinical MRI complexity: a first step towards realizing the maximum research value of neuroradiological MRI.
Marzena Wylezinska-Arridge1, Mark J White1,2, Indran Davagnanam1, M Jorge Cardoso3, Sjoerd B Vos3,4, Sebastien Ourselin3, Olga Ciccarelli5, Tarek Yousry1, and John Thornton1,2

1Neuroradiological Academic Unit, UCL Institute of Neurology, University College London, London, United Kingdom, 2Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, London, United Kingdom, 3Translation Imaging Group, Centre for Medical Imaging Computing, University College London, London, United Kingdom, 4MRI Unit, Epilepsy Society, Chalfont, St Peters, United Kingdom, 5Institute of Neurology, University College London, London, United Kingdom

The huge number of hospital MRI examinations routinely obtained for clinical purposes offers a potentially valuable “big data” resource for largescale experimental neurology. However, acquisition-scheme variation may compromise the research value of clinical imaging data. A first step towards reducing variation by prospective protocol harmonization is to systematically capture sequence-use statistics. Using an in-house tool developed to automate capture of long-term, MRI sequence deployment statistics in routine practice within our neuroradiological service, we identified “core“, most used sequences and the deployment frequency of their respective variants, to enable efficient, targeted protocol harmonization.

12:45
Adjournment & Meet the Teachers


Plenary Session

Welcome & Awards

7:30 - 8:30


Traditional Poster -

Exhibition Hall 14:15 - 16:15 (no CME credit)

Electronic Poster : Contrast Mechanisms

Exhibition Hall 14:15 - 15:15 (no CME credit)

Electronic Poster : Body

Exhibition Hall 15:15 - 16:15 (no CME credit)

Study Groups

Current Issues in Brain Function

Hall 405 E 14:15 - 16:15


Study Groups

Detection & Correction of Motion in MRI & MRS

Hall 406 D 14:15 - 16:15


Power Pitch

Novel Acquisitions & Reconstruction Strategies

Power Pitch Theatre, Exhibition Hall 14:15 - 15:15 Moderators:David Brunner & Ian Marshall

91 14:15
Phaseless Encoding
Franciszek Hennel1 and Klaas P. Pruessmann1

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

92 14:18
Rabi Modulated Continuous Wave Imaging
James C Korte1, Bahman Tahayori1, Peter M Farrell1, Stephen M Moore2,3, and Leigh A Johnston1

1Dept. Electrical and Electronic Engineering, University of Melbourne, Melbourne, Australia, 2IBM Research, Melbourne, Australia, 3Dept. Mechanical Engineering, University of Melbourne, Melbourne, Australia

93 14:21
Gradient Free MRI with a rotating magnet and receiver fields
Somaie Salajeghe1, Paul Babyn2, Logi Vidarsson3, and Gordon E. Sarty1

1Biomedical Engineering, University of Saskatchewan, Saskatoon, SK, Canada, 2Medical Imaging, University of Saskatchewan, Saskatoon, SK, Canada, 3LT Imaging, Toronto, ON, Canada

94 14:24
Cyclic Continuous Max-Flow: Phase Processing Using the Inherent Topology of Phase
John Stuart Haberl Baxter1, Zahra Hosseini1, Junmin Liu2, Maria Drangova3, and Terry M Peters1

1Biomedical Engineering Graduate Program, Western University, London, ON, Canada, 2Imaging Laboratories, Robarts Research Institute, London, ON, Canada, 3Department of Medical Biophysics, Western University, London, ON, Canada

95
14:27
a-f BLAST: A Non-Iterative Radial k-t BLAST Reconstruction in Radon Space
Madison Kretzler1, Jesse Hamilton2, Mark Griswold2,3, and Nicole Seiberlich2,3

1Electrical Engineering, Case Western Reserve University, Cleveland, OH, United States, 2Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, 3Radiology, University Hospitals, Cleveland, OH, United States

96
14:30
Model-based Reconstruction for Real-Time Phase-Contrast Flow MRI - Improved Spatiotemporal Accuracy
Zhengguo Tan1, Volkert Roeloffs1, Dirk Voit1, Arun Joseph1, Markus Untenberger1, Klaus-Dietmar Merboldt1, and Jens Frahm1

1Biomedizinische NMR Forschungs GmbH, Max-Planck-Institute for Biophysical Chemistry, Goettingen, Germany

97 14:33
Acquisition of high resolution three-dimensional ocular images at 7 Tesla to generate patient-specific eye-models for clinical ray-tracing
Jan-Willem Beenakker1, Lucia Hervella2, Juan Tabarnero2, Dennis Shamonin1, Andrew Webb1, Gregorius Luyten1, and Pablo Artal2

1Leiden University Medical Centre, Leiden, Netherlands, 2University of Murcia, Murcia, Spain

98 14:36
Perfusion map derived from resting state fMRI
Yunjie Tong1, Kimberly P Lindsey1, Lia M Hocke2, Gordana Vitaliano1, Dionyssios Mintzopoulos1, and Blaise B Frederick1

1McLean Hospital/Harvard Medical School, Belmont, MA, United States, 2Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada

99 14:39
Nonlinear RF spatial encoding with multiple transmit coils based on Bloch-Siegert shift
Yuqing Wan1, Maolin Qiu1, Gigi Galiana1, and R. Todd Constable1

1Radiology and Biomedical Imaging, Yale University, New Haven, CT, United States

100 14:42
The role of brain viscoelasticity in chronically shunted hydrocephalus using Magnetic Resonance Elastography
Kristy Tan1, Adam L. Sandler2, Avital Meiri1, Rick Abbott2, James T. Goodrich2, Eric Barnhill3, and Mark E. Wagshul1

1Gruss MRRC, Albert Einstein College of Medicine, Bronx, NY, United States, 2Department of Neurological Surgery, Albert Einstein College of Medicine/Children’s Hospital at Montefiore, Bronx NY, Bronx, NY, United States, 3Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, United Kingdom

101 14:45
Prospective Motion Correction With NMR Markers Using Only Native Sequence Elements
Alexander Aranovitch1, Maximilian Haeberlin1, Simon Gross1, Thomas Schmid1, and Klaas Paul Pruessmann1

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

102 14:48
Whole-brain quantitative diffusion MRI at 660 µm resolution in 25 minutes using gSlider-SMS and SNR-enhancing joint reconstruction
Justin P Haldar1, Qiuyun Fan2, and Kawin Setsompop2

1Electrical Engineering, University of Southern California, Los Angeles, CA, United States, 2A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States

103 14:51
Joint K-space Trajectory and Parallel Imaging Optimization for Auto-calibrated Image Reconstruction
Stephen Cauley1,2, Kawin Setsompop1,2, Berkin Bilgic1, Himanshu Bhat3, Borjan Gagoski2,4, Thomas Witzel1,2, and Lawrence L. Wald1,2,5

1MGH/HST, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Siemens Medical Solutions Inc, Malvern, PA, United States, 4Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Boston, MA, United States, 5Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, MA, United States

104 14:54
Looping star: A novel, self-refocusing zero TE imaging strategy
Ana Beatriz Solana1, Anne Menini1, and Florian Wiesinger1

1GE Global Research, Garching bei Muenchen, Germany

105 14:57
Real-time SENSE reconstruction using pre-scan and E-maps sensitivities
Muhammad Faisal Siddiqui1, Abubakr Shafique2, Yousif Rauf Javed2, Talha Ahmad Khan2, Hamza Naeem Mughal2, Ahmed Wasif Reza1, Hammad Omer2, and Jeevan Kanesan1

1Electrical Engineering, University of Malaya, Kuala Lumpur, Malaysia, 2Electrical Engineering, COMSATS Institute of Information Technology, Islamabad, Pakistan

106 15:00
Do try this at home: the role of CAIPIRINHA and non-Cartesian techniques for increased throughput and aesthetic enhancement in baking  (or vice versa)
Benedikt A Poser1

1Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands


Oral

Brain Metabolism

Room 300-302 14:15 - 16:15 Moderators:Gary Egan & Eric Schrauben

107 14:15
Dietary Restriction Improved Memory and Neuronal Metabolism in AβPP-PS1 Mouse Model of Alzheimer’s Disease: A 1H-[13C]-NMR Study
Anant Bahadur Patel1 and Kamal Saba1

1NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India

Alzheimer's disease (AD) is the most common neurodegenerative disorders. Currently no effective treatment available for AD. Dietary restriction (DR) has been shown to improve longevity in rodents. In the present study, we evaluated the effects of DR on memory and brain energy metabolism in AβPP-PS1 mouse model of AD using 1H-[13C]-NMR spectroscopy in conjunction with infusion of [1,6-13C2]glucose. Our findings suggest that DR intervention had improved the memory and the neuro-metabolic activity in the AD mice.

108
14:27
A 1H-[13C]-NMR Study for Understanding Antidepressant Action of Lanicemine in Chronic Unpredictable Mild Stress Model of Depression
Pravin K Mishra1 and Anant Bahadur Patel1

1NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India

Though, ketamine possess rapid antidepressant properties, its use is limited due to addictive and psychotomimetic properties. In the current study, we have evaluated the antidepressant activity of lanicemine in CUMS model of depression by 1H-[13C]-NMR spectroscopy together with infusion of [1,6-13C2]glucose. Exposure of lanicemine restored behavioral phenotype and activity of excitatory and inhibitory neurons in depression.

109 14:39
Brain Glycogen Supercompensation: A Role in the Development of Hypoglycemia Unawareness?
Gulin Oz1, Mauro DiNuzzo2, Anjali Kumar3, Amir Moheet3, Kristine Kubisiak4, Lynn E. Eberly4, and Elizabeth R. Seaquist3

1Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 2Museo storico della fisica e Centro di studi e ricerche Enrico Fermi, Rome, Italy, 3Medicine, University of Minnesota, Minneapolis, MN, United States, 4Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States

Supercompensated brain glycogen levels may contribute to the development of hypoglycemia associated autonomic failure (HAAF) following recurrent hypoglycemia (RH) by providing energy for the brain during subsequent periods of hypoglycemia. To assess the role of glycogen supercompensation in the generation of HAAF, we estimated the level of brain glycogen supercompensation following RH using 13C MRS and compared it to that following acute hypoglycemia (AH). Glycogen levels were found to increase after both AH and RH, but to a lesser extent after RH. These data suggest that glycogen supercompensation may be an epiphenomenon of HAAF.

110
14:51
In vivo detection of hypothalamic glucose metabolism in HFD and regular fed mice
Blanca Lizarbe1, Antonie Cherix1, Lijing Xin2, Hongxia Lei2,3, and Rolf Gruetter1,3,4

1Laboratory for Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 2Animal imaging and technology core (AIT), Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, Lausanne, Switzerland, 3Department of Radiology, University of Geneva, Geneva, Switzerland, 4Department of Radiology, University of Lausanne, Lausanne, Switzerland

Obesity is a pandemic syndrome that leads to reduced life expectancy, increasing the risk of heart disease, type-2 diabetes and some type of cancers.  Noteworthy, to understand the mechanisms of obesity onset and development, several animal models, such as administration high fat diets, have been developed. We used 1H-[13C] MRS methods in regular and in high fat diet fed mice to investigate the effects of high caloric diets and obesity in the hypothalamus, its effects in glucose metabolism and metabolic fluxes in neurons and glia. We found differences that suggest impaired glucose metabolism in the hypothalamus of obese mice.

111 15:03
Amide proton signals as pH indicator for in vivo MRS and MRI of the brain – Responses to hypercapnia and hypothermia
Takashi Watanabe1, Jens Frahm1, and Thomas Michaelis1

1Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany

Using proton MRS/MRI of mouse brain at 9.4 T, this work provides the first in vivo evidence of concurrent pH-dependent changes of amide signals and related metabolic responses to hypercapnia and hypothermia. During hypercapnia, amide MRS signals of glutamine and of unspecific compounds increase by ≥50% at 37°C and 22°C. They are strongly correlated with intracellular pH determined from a shift in creatine phosphokinase equilibrium. In MRI, saturation transfer to water protons alters signal intensities in dependence on pH and temperature. Irradiation of aliphatic compounds at -3.5 ppm frequency offset from water predominantly saturates lipids and water associated with myelin.

112 15:15
Assessing metabolic and structural alterations of brain cells in the APP/PS1/tauP301L mouse model of Alzheimer’s disease using MRS and diffusion-weighted MRS in vivo
Clemence Ligneul1,2, Marco Palombo1,2, Juliette Le Douce1,2, Pierrick Jego1,2, Martine Guillermier1,2, Gilles Bonvento1,2, and Julien Valette1,2

1CEA/DSV/I2BM/MIRCen, Fontenay-aux-Roses, France, 2CNRS Université Paris-Saclay UMR 9199, Fontenay-aux-Roses, France

In this work we use in vivo MRS and diffusion-weighted MRS to detect alterations in cellular metabolism and structure in a triple transgenic APP/PS1/tauP301L mouse model of Alzheimer’s disease. We are able to detect massive remodeling of metabolic content in the hippocampus, as well as subtle but significant variations in diffusion properties of astrocytic metabolites. These results are essentially consistent with the metabolic and structural signature of activated astrocyte, a cell status represented around amyloid plaques.

113 15:27
Brain Sodium MRI depicts upper motor neuron involvement in Amyotrophic Lateral Sclerosis patients
Aude-Marie Grapperon1, Adil Maarouf2,3, Annie Verschueren1, Amandine Sevy1, Elisabeth Soulier2, Sylviane Confort-Gouny2, Patrick Viout2, Jean-Philippe Ranjeva2, Maxime Guye2,3, Sharham Attarian1, and Wafaa Zaaraoui2

1APHM, Hôpital Timone, Pôle Neurosciences, Marseille, France, 2CRMBM - CNRS - Aix-Marseille Université, Marseille, France, 3APHM, Hôpital Timone, CEMEREM, Marseille, France

Amyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disease that involves the death of upper (in brain) and lower (in spine) motor neurons. As conventional MRI failed to show brain motor neurons impairment in ALS, advanced techniques are needed to improve the diagnosis of the disease and monitor its progression. 23Na brain MRI was performed to 4 ALS patients and showed accumulation of sodium in the primary motor areas in the 3 patients presenting with clinical brain motor neuron signs. Besides, more patients were clinically affected, more the sodium accumulation was extended. In conclusion, sodium accumulation, which is an indicator of neuronal injury, could be a marker of ALS diagnosis and disease progression.

114
15:39
Modulations of cerebral TCA cycle activity studied by hyperpolarized Acetate 13C MRS
Elise Vinckenbosch1, Mor Mishkovsky1, Arnaud Comment2, and Rolf Gruetter1,3

1Laboratory of functional and metabolic imaging, EPFL, Lausanne, Switzerland, 2Institute of Physics of Biological Systems, EPFL, Lausanne, Switzerland, 3Department of Radiology, University of Lausanne and Geneva, Lausanne, Switzerland

Hyperpolarized [1-13C] acetate enables for in vivo detection of 2-oxoglutarate, a tricarboxylic acid (TCA) cycle intermediate, in intact brain at high field. The aim of this study is to examine saturation substrate dose conditions and to compare it with a partially inhibited TCA cycle model. We conclude that 2-oxoglutarate production rate can be calculated as a function of varying substrate concentrations and is affected as well as the cerebral acetate kinetics by TCA cycle activity modulations.

115 15:51
Brain lactate concentration falls in response to hypoglycemia in type 1 diabetes patients with impaired awareness of hypoglycemia
Evita Wiegers1, Hanne Rooijackers2, Cees Tack2, Arend Heerschap1, Bastiaan de Galan2, and Marinette van der Graaf1,3

1Radiology and Nuclear Medicine, Radboud umc, Nijmegen, Netherlands, 2Internal Medicine, Radboud umc, Nijmegen, Netherlands, 3Pediatrics, Radboud umc, Nijmegen, Netherlands

TThe effect of hypoglycemia on cerebral lactate concentration was assessed in patients with type 1 diabetes (T1DM) and impaired awareness of hypoglycemia (IAH), patients with normal awareness of hypoglycemia (NAH) and in healthy subjects. Brain lactate concentrations were determined during stable euglycemic and stable hypoglycemic conditions using a J-editing semi-LASER 1H-MRS sequence at 3T. We found a 20% decrease in brain lactate concentration in T1DM patients with IAH in response to hypoglycemia, which may reflect increased lactate oxidation. No changes in cerebral lactate concentrations were observed in the other two groups.

116 16:03
Differential Metabolic Profiles in Rat Retrosplenial Cortex, Cingulate Cortex and Medial Prefrontal Cortex: Relationship with Cytoarchitecture and Functional Implications
Hui Zhang1 and Hao Lei1

1National Center of Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China, People's Republic of

In this study, we measured regional neurochemical variations in rat prelimbic cortex (PrL)/infralimbic cortex (IL), cingulate cortex (Cg) and retrosplenial cortex (RSC)  with in vivo 1H-MRS at 7T. It was found that the regional metabolic variations follow cytoarchitectural/receptor-architectonical organization in these brain regions.


Oral

Diffusion Tractography

Room 324-326 14:15 - 16:15 Moderators:Qiuyun Fan & J-Donald Tournier

117 14:15
U-fiber Quantification in Non-Lesional Epilepsy
Rafael O'Halloran1, Rebecca Feldman1, Madeline Fields1, Laura Marcuse1, and Priti Balchandani1

1Icahn School of Medicine at Mount Sinai, New York, NY, United States

A method for the quantification of cortical-to-cortical U-fiber fraction based on 7T MRI is presented and used to demonstrate group differences in the the U-fiber fractions in non-lesional and lesional epilepsy patients compared to healthy controls. Non-lesional epilepsy patients had the lowest u-fiber fractions followed by healthy control subjects, and then by lesional epilepsy subjects with the highest u-fiber fractions.

118 14:27
The influence of node assignment strategies and track termination criteria on diffusion MRI-based structural connectomics
Chun-Hung Yeh1, Robert Elton Smith1, Thijs Dhollander1, Fernando Calamante1, and Alan Connelly1

1The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia

This study highlights the issue of using the common strategy for assigning individual streamlines to an atlas-based brain parcellation. This process is non-trivial and can introduce ambiguity into connectome quantification. In many fibre-tracking algorithms, track termination criteria can cause premature termination of streamlines within WM or CSF, which can result in up to ~50–80% of streamlines failing in identifying pairwise connections between nodes from streamline endpoints. Our results demonstrate that such issue can be largely ameliorated through the combination of biologically meaningful track terminations and an appropriate node assignment mechanism. This could therefore be advantageous to structural connectome construction.

119 14:39
Behavioral response time as explained by a fiber-based analysis of generalized fractional anisotropy measured using diffusion spectrum imaging
Kayako Matsuo1, Yung-Chin Hsu2, Yasuo Takehara3, Wen-Yih Isaac Tseng2, and Norio Mori1

1Dept. Psychiatry, Hamamatsu University School of Medicine, Hamamatsu, Japan, 2Institute of Medical Devices and Imaging System, National Taiwan University College of Medicine, Taipei, Taiwan, 3Dept. Radiology, Hamamatsu University School of Medicine, Hamamatsu, Japan

DSI on a GE 3T was conducted for 22 normal controls to examine the neural basis of the response time (RT). RT was measured outside the scanner using button pressing by left or right hand in response to visual or auditory stimulation. Faster RT was associated with greater GFA of portions near the cortical hand area in the corticospinal tract (CST). Left and right hand specializations were found in the deeper CST. Greater GFA in portions near the cortex in the left auditory radiation was associated with faster RT by visual stimulations, suggesting an influence of language processing speed.

120 14:51
Image quality transfer benefits tractography of low-resolution data
Daniel C. Alexander1, Aurobrata Ghosh1, Samuel A. Hurley2, and Stamatios N. Sotiropoulos2

1Computer Science, UCL, London, United Kingdom, 2FMRIB, Oxford University, Oxford, United Kingdom

We show benefits of image quality transfer to tractography. Diffusion MRI super-resolution through image quality transfer enables recovery of thin tracts in a dataset with low spatial resolution (2.5mm isotropic). Specifically, we reconstruct four pathways arising from the motor area that have been distinguished before when using high (1.25mm) resolution HCP data. Quantitative results confirm that image quality transfer enhances tractography more than standard interpolation. The results highlight the major potential of image quality transfer in learning information from bespoke high quality data sets to enhance the specificity of information derived from more modest but readily available data.

121 15:03
QuickBundlesX: Sequential clustering of millions of streamlines in multiple levels of detail at record execution time
Eleftherios Garyfallidis1, Marc-Alexandre Côté1, François Rheault1, and Maxime Descoteaux1

1Computer Science, Université de Sherbrooke, Sherbrooke, QC, Canada

QuickBundlesX shows a remarkable 20+X speedup over it’s predecessor who was until today the fastest clustering algorithm for streamlines. In addition, it returns a useful tree of clusters at different resolutions which allows to query streamlines and easily process millions of streamlines by comparing only with their neighbours.

122 15:15
Structural Fingerprinting of the Human Brain: How unique is tract shape to the individual?
Greg D Parker1, George J.A. Evans2, and Derek K Jones1,3

1CUBRIC, School of Psychology, Cardiff University, Cardiff, United Kingdom, 2School of Medicine, Newcastle University, Newcastle, United Kingdom, 3Neuroscience and Mental Health Research Institute (NMHRI), School of Medicine, Cardiff University, Cardiff, United Kingdom

Even amongst healthy subjects, brain function and structure is known to be highly variable across individuals1,2. Recently3 it was shown that inter-subject variation in functional connectivity is sufficient to allow robust and reliable identification of individuals across different sessions and tasks. Here we demonstrate for the first time that the same is true of white matter structure; using the shape of an individual's white matter tracts we generate fingerprints that uniquely identify individuals across different scan sessions.

123 15:27
Fibers crossing the white/gray matter boundary: a semi-global, histology-informed dMRI model
Michiel Cottaar1, Matteo Bastiani1, Charles Chen2, Krikor Dikranian2, David C. Van Essen2, Timothy E. Behrens1, Stamatios N. Sotiropoulos1, and Saad Jbabdi1

1FMRIB, Oxford University, Oxford, United Kingdom, 2Washington University School of Medicine, Saint Louis, MO, United States

Close to the cortical white/gray matter boundary surface fiber orientations sharply transition from being nearly tangential to the surface in the white matter to mostly radial in the gray matter. We propose a geometric model that describes this transition at sub-voxel resolution based on high-resolution histology data and fit this model to lower resolution diffusion MRI data. We assess its performance using qualitative comparisons with histology and test the reproducibility of the estimated parameters across multiple diffusion MRI resolutions. This model allows the in-vivo estimation of fiber orientations across the white/gray matter boundary, which may improve tracking to the cortex.

124 15:39
Microscopic DTI for quantitative tractography of MAP6-KO mice: validation by fluorescent microscopy on cleared brains
Ulysse Gimenez1, Franck Mauconduit1, Benoit Boulan2, Eric Denarier2, Jacques Brocard2, Sylvie Gory-Fauré2, Annie Andrieux2, Jean Christophe Deloulme2, and Hana Lahrech1

1Clinatec Lab U1205, INSERM, Grenoble, France, 2Grenoble Institute of Neurosciences, INSERM, La Tronche, France

High spatial resolution 3D DTI was developed and used for white matter tractography to quantify neuronal tract alterations on the MAP6-KO mouse. In this model, the microtubule-associated protein 6 (MAP6) which is involved in the neuromorphogenesis is deleted leading to a model characterized by severe behavior impairments, similar to the clinical features of schizophrenia. As 3D DTI tractography and fluorescent microscopy on cleared brains both show a deficiency of the post-commissural fornix, in accordance with our previous 2D DTI results, the 3D DTI tractography imaging is validated. Using 3D DTI tractography, new major alterations in different neuronal tracts are detected. 

125 15:51
Network integration and segregation differentiate between Alzheimer Disease and Vascular Dementia
Fulvia Palesi1,2, Andrea De Rinaldis2,3, Letizia Casiraghi2,4, Gloria Castellazzi2,3, Paolo Vitali5, Nicoletta Anzalone6, Federica Denaro7, Elena Sinforiani8, Giuseppe Micieli7, Egidio D'Angelo2,4, and Claudia Angela Michela Gandini Wheeler-Kingshott2,9

1Department of Physics, University of Pavia, Pavia, Italy, 2Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy, 3Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy, 4Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy, 5Brain MRI 3T Mondino Research Center, C. Mondino National Neurological Institute, Pavia, Italy, 6Scientific Institute H. S. Raffaele, Milan, Italy, 7Department of Emergency Neurology, C. Mondino National Neurological Institute, Pavia, Italy, 8Alzheimer's Disease Assessment Unit, Laboratory of Neuropsychology, C. Mondino National Neurological Institute, Pavia, Italy, 9NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom

Dementia is the most common disorder in elderly people and comprises Alzheimer’s disease (AD) and vascular disease (VaD). In this work graph theoretical approach was applied to a cohort of AD, VaD and healthy controls (HC) aimed at investigating the presence of a disease-specific pattern of alterations. Brain structural networks were built using the Cohen functional atlas (nodes) and advanced probabilistic tractography (edges). Our main finding was that VaD patients showed severe impairment in the large-scale brain networks while AD patients mainly showed inefficiency of short-range connections emphasizing the fact that alterations are restricted to specific brain regions.

126 16:03
Estimating Network Topology in Weighted and Dense Connectomes
Luis Manuel Colon-Perez1, Michelle Couret2, William Triplett3, Catherine Price3, and Thomas H Mareci3

1Psychiatry, University of Florida, Gainesville, FL, United States, 2Medicine, Columbia University, New York, NY, United States, 3University of Florida, Gainesville, FL, United States

Brain networks are organized in a heterogeneous range of white-matter tract sizes suggesting that the brain is organized in broad range of white matter connection strengths. Studies of brain structure with a binary connection model have shown a small-world network topological organization of the brain. We developed a generalized framework to estimate the topological properties of brain networks using weighted connections, which offers a more realistic model of the brain compared to the binary connection model. In addition, this model reduces the need for thresholding to obtain topological properties in dense and weighted connectomes.


Oral

Tumour Response to Therapy

Room 331-332 14:15 - 16:15 Moderators:Richard Do & Sabrina Ronen

127 14:15
Texture Feature Analysis of Quantitative and Semi-Quantitative DCE-MRI Metrics for Early Prediction of Breast Cancer Therapy Response
Guillaume Thibault1, Alina Tudorica2, Aneela Afzal2, Stephen Chui2, Arpana Naik2, Megan Troxell3, Kathleen Kemmer2, Karen Oh2, Nicole Roy2, Megan Holtorf2, Wei Huang2, and Xubo Song2

1BME, OHSU, Portland, OR, United States, 2OHSU, Portland, OR, United States, 3OHSU, portland, OR, United States

36 breast cancer patients underwent research DCE-MRI before and after one cycle of neoadjuvant chemotherapy.  3D tumor imaging texture features were extracted from parametric maps of quantitative pharmacokinetic (PK) and semi-quantitative DCE-MRI parameters, and correlated with pathologically measured post-therapy residual cancer burden (RCB).  Texture features from quantitative PK parameters were found to be more useful than those from semi-quantitative metrics for early prediction of therapy response, while the features from the SSM PK parameters were superior to the SM counterparts for prediction of response.

128 14:27
Role of the Intravoxel Incoherent Motion (IVIM) Imaging in the Pre-treatment Prediction and Early Response Monitoring for Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer
Shunan Che1, Chunwu Zhou1, Xinming Zhao1, Jing Li1, and Bing Wu2

1department of radiology, Cancer Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China, People's Republic of, 2GE Healthcare MR Research China, Beijing, China, People's Republic of

Purpose: to explore whether IVIM can determine pre-treatment differences or monitor early response in breast cancer patients receiving NAC. Materials and Methods: thirty-six patients examined with multiple-b DWI were divided into MHR and NMHR groups. Parameters between MHR and NMHR groups were compared. Results: the D and f value at the baseline and mid-treatment of NAC showed significantly differences between MHR and NMHR. △D and △f were significantly higher in MHR than in NMHR. Conclusion: the D and f value showed potential value in the pre-treatment prediction and early response monitoring to NAC in local advanced breast.

129
14:39
Evaluation of FLAIR maps by PRM provides for glioma response assessment
Deborah Sharon Honrado Guest1, Craig Galbán1, Gary Luker1, Thomas Chenevert1, Benjamin Lemasson2, Robin Johannes Marius Navest3, Klaas Nicolaij3, and Brian Ross1

1Radiology, University of Michigan, Ann Arbor, MI, United States, 2Institut des Neurosciences, Université Grenoble Alpes, Grenoble, France, 3Department of Biomedical Engineering, Technische Universiteit Eindhoven, EINDHOVEN, Netherlands

This study investigates the possibility of adapting the PRM method for use with normalized FLAIR images to predict OS and TTP for indication of tumor recurrence. Glioma patients were separated into non-responders and responders to treatment. Voxels present in the union of the VOIs for the rFLAIR images were used to evaluate the PRMrFLAIR values and categorize patients into groups based on changes in signal intensity. This study shows that predicting TTP and OS is achievable using PRM with rFLAIR maps for patients treated with TMZ/IR and provides the first demonstration of quantifying FLAIR signals in patients over time.  

130
14:51
Intracellular-extracellular water exchange as a biomarker of tumor response to stereotactic radiosurgery
Hatef Mehrabian1,2, Kimberly L Desmond3, Arjun Sahgal1,4, Hany Soliman1,4, Anne L Martel1,2, and Greg J Stanisz1,2

1Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada, 2Medical Biophysics, University of Toronto, Toronto, ON, Canada, 3Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, Canada, 4Radiation Oncology, Odette Cancer Centre, Toronto, ON, Canada

Targeted radiation treatments are expected to induce DNA damage in tumor cells which leads to apoptosis. Apoptotic cells experience an increase in cell membrane permeability and surface-to-volume ratio, both of which result in increased water exchange rate between intracellular and extracellular compartments.

Using a three compartment relaxation model we demonstrate that early changes in intracellular-extracellular water exchange correlated well with tumor volume change one-month post-treatment. Moreover, when the water exchange rate was combined with early tumor volume change and was employed in a classifier, the patients with partial response and progressing disease could be identified with a very high accuracy.


131
15:03
Multimodality functional imaging in radiation therapy during treatment: relationship between DW-MRI and 18F FDG PET in head and neck squamous cell carcinoma
David Aramburu Nuñez1,2, Antonio Lopez Medina3, Moises Mera Iglesias4, Francisco Salvador Gomez5, Vaios Hatzoglou6, Ramesh Paudyal1, Alfonso Calzado2, Joseph O Deasy1, Amita Shukla-Dave7, and Victor M Muñoz8

1Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 2Department of Radiology, Complutense University, Madrid, Spain, 3Medical Physics & Radiological Protection, Galaria - Hospital do Meixoeiro – Complexo Hospitalario Universitario de Vigo, Vigo, Spain, 4Medical Physics, Oncoserv, Santiago de los Caballeros, Dominican Republic, 5Medical Physics and Radiological Protection, Galaria - Hospital do Meixoeiro – Complexo Hospitalario Universitario de Vigo, Vigo, Spain, 6Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 7Medical Physics & Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 8Radiation Oncology, Galaria - Hospital do Meixoeiro – Complexo Hospitalario Universitario de Vigo, Vigo, Spain

Biologically guided radiotherapy needs an understanding of how different functional imaging techniques interact and link together. DW-MRI and 18F FDG-PET techniques were used in this study for achieving this objective. 5 HPV-, HNSCC patients underwent 20 DW-MRI and 10 18F-FDG-PET/CT scans before and during radiation therapy. ADC maps derived from DW-MRI and SUV values from 18F-FDG were used for evaluating tumor response. The initial evaluation of the preliminary results suggests that in these solid tumors cellularity is inversely proportional to the glucose metabolic uptake. The survival status and functional metrics show different trends for NED, AWD and DOD. 

132 15:15
MRI in predicting the response of gastrointestinal stromal tumor to targeted therapy: a patient-based multi-parameter study
Lei Tang1, Jian Li2, Ying-Shi Sun1, Xiao-Ting Li1, Zi-Yu Li3, Xiao-Yan Zhang1, and Lin Shen 2

1Radiology, Peking University Cancer Hospital & Institute, Beijing, China, People's Republic of, 2GI medicine, Peking University Cancer Hospital & Institute, Beijing, China, People's Republic of, 3GI surgery, Peking University Cancer Hospital & Institute, Beijing, China, People's Republic of

The percentage changes of the ADC in GIST after two weeks of targeted therapy exhibited reliable performance in response prediction, and these variables outperformed T2WI-CNR and the longest diameter. We suggest that patients continue their treatment regimens if the percentage increases in the ADC are no less than 15% after two weeks of therapy. In contrast, if the ADC decreases or exhibits almost no change, then a shortening of the follow-up time intervals is highly recommended to detect possible drug resistance at an early stage.

133
15:27
Quantitative MRI and optoacoustic imaging tracks treatment response in tumor
Prashant Chandrasekharan1, Ghayathri Balasundaram1, Amalina Binte Ebrahim Attia1, Chris Jun Hui Ho1, Xuan Vinh To1, Hui Chien Tay1, Kai Hsiang Chuang1, and Malini Olivo1

1A*STAR, Singapore Bio Imaging Consortium, Singapore, Singapore

Quantification of oxygenation or hypoxia in a tumor plays a key role in the treatment response and the overall survival of glioma patient.  This work illustrates a preclinical study with the use of multimodal imaging technique to correlate tumor oxygenation and blood perfusion, as well as to assess the changes involved in the perturbation of the tumor system using a vascular disruptive agent.

134
15:39
Assessment of early treatment response by IVIM DW-MRI and DCE-MRI in patients with brain metastases treated with stereotactic radiosurgery.
David Aramburu Nuñez1,2, Kathryn Beal3, Vaios Hatzoglou4, Andrei Holodny4, Ramesh Paudyal1, Yonggang Lu5, Joseph O Deasy1, and Amita Shukla-Dave6

1Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 2Department of Radiology, Complutense University, Madrid, Spain, 3Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 4Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 5Radiation Oncology, Washington University, St. Louis, MO, United States, 6Medical Physics & Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States

In clinical settings it is essential to accurately assess, whether or not a brain metastasis has been successfully treated or whether the metastasis require additional treatment. This is the first study that evaluated brain metastases with IVIM DW-MRI and DCE-MRI data both pre- and post- stereotactic radiosurgery (SRS). The preliminary results are promising as it will inform the treating physicians at an early time point about which patients will benefit from SRS (or not). The survival status and functional metrics show different trends for both AWD and DOD that need to be validated in larger patient population.

135 15:51
T1 is a biomarker of therapy-induced cell death in the Th-MYCN genetically-engineered murine model of neuroblastoma.
Yann Jamin1, Evon S.C. Poon2, Albert Hallsworth2, Hannah Webber2, Laura S. Danielson2, Dow-Mu Koh1, Louis Chesler2, and Simon P. Robinson1

1Division of Radiotherapy & Imaging, The Institute of Cancer Research, London, United Kingdom, 2Division of Cancer Therapeutics and Division of Clinical Studies, The Institute of Cancer Research, London, United Kingdom

In this study we demonstrate that T1 provides a non-invasive biomarker of response to MLN8237, a potent Aurora A kinase inhibitor, in the Th-MYCN genetically-engineered murine model of neuroblastoma, a childhood cancer of the nervous system. Histopathological characterisation demonstrates that T1 is a generic biomarker of cell death in this model. T1 quantification in pediatric early-phase clinical trials could potentially help to accelerate the development of urgently needed novel targeted therapies for children with neuroblastoma. 

136
16:03
Can anti-VEGF Antibody Reverse Radiation Necrosis? A Preclinical Investigation
Chong Duan1, Carlos J Perez-Torres2, Liya Yuan3, John A Engelbach4, Christina T Tsien5, Keith M Rich3,5, Robert E Schmidt6, Joseph JH Ackerman1,4,7,8, and Joel R Garbow4,8

1Chemistry, Washington University in St. Louis, St. Louis, MO, United States, 2Radiological Health Sciences, Purdue University, West Lafayette, IN, United States, 3Neurosurgery, Washington University in St. Louis, St. Louis, MO, United States, 4Radiology, Washington University in St. Louis, St. Louis, MO, United States, 5Radiation Oncology, Washington University in St. Louis, St. Louis, MO, United States, 6Neuropathology, Washington University in St. Louis, St. Louis, MO, United States, 7Medicine, Washington University in St. Louis, St. Louis, MO, United States, 8Alvin J Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO, United States

Recently, radiation necrosis (RN) has been treated clinically using bevacizumab, an anti-VEGF antibody. While bevacizumab reduces radiographic RN volume, the treatment has potentially serious complications and rebound phenomena after the discontinuation of the therapy. In the present study, we investigated the anti-VEGF treatment of pure radiation necrosis in a mouse model. Favorable radiographic appearance of RN were observed following the anti-VEGF treatment. However, the lesions were not completely resolved histologically (e.g., focal mineral deposits were observed in the treated mice). In addition, despite the treatment, VEGF and HIF-1α were still upregulated, which presents the potential risk of recurrence of RN.


Oral

Myocardial Viability & Clinical Studies

Room 334-336 14:15 - 16:15 Moderators:Vincent Ho & Taehoon Shin

137 14:15
Fully Automatic Left Atrium and Pulmonary Veins Segmentation for Late Gadolinium Enhanced MRI Combining Contrast Enhanced MRA
Qian Tao1, Esra Gucuk Ipek2, Rahil Shahzad1, Floris F. Berendsen1, Saman Nazarian2, and Rob J. van der Geest1

1Department of Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Department of Cardiology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States

The extent and distribution of left atrial (LA) scar, visualized by LGE MR, can provide important information for treatment of atrial fibrillation (AF) patients. However, in current practice, to extract such information requires substantial manual effort and expertise. In this study, a fully automatic method was developed to segment LA and PV’s in LGE-MRI, combining robust multi-atlas segmentation and flexible level-set based segmentation optimization. The method demonstrated comparable accuracy to manual segmentation, with improved 3D continuity. The method enables automated generation of patient-specific LA and PV geometry models, and potentially objective LA scar assessment for individual AF patients.

138 14:27
Dark Blood Late Gadolinium Enhanced Imaging of Myocardial Scar using First-Moment-Nulled Motion Sensitized Driven Equilibrium (m2MSDE)
Gregory J Wilson1, Niranjan Balu1, Jinnan Wang1,2, Chun Yuan1, and Jeffrey H Maki1

1University of Washington, Seattle, WA, United States, 2Bayer Healthcare, Whippany, NJ, United States

A novel black-blood pre-pulse is described that darkens intraventricular blood pool signal in late gadolinium enhanced (LGE) imaging of myocardial scar. The pre-pulse is m1-nulled motion-sensitized driven equilibrium (m2MSDE) with user-specified motion-sensitizing direction. The pre-pulse nulls blood signal while maintaining good myocardial image quality. Preliminary results are described.

139 14:39
Visual quality assessment of 3D High Resolution Late Gadolinium Enhancement with Compressed-Sensing in a Clinical Setting: the impact of patient factors
Charlene Liew1,2, Tamer Basha1, Mehmet Akcakaya1, Connie Tsao1, Francesca Delling1, Kraig Kissinger1, Beth Goddu1, Sophie Berg1, Warren Manning1,3, and Reza Nezafat1

1Division of Cardiology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, United States, 2Department of Radiology, Changi General Hospital, Singapore, Singapore, 3Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, United States

Compressed sensing can be used to reduce 3D LGE scan time by factor of 5 with isotropic spatial resolution. However, clinical feasibility and overall image quality of 3D LGE with compressed sensing is still unknown. In this study, we sought to assess the image quality of 3D LGE with isotropic spatial resolution of 1-1.5 mm3 in 268 consecutive patients with known or suspected cardiovascular disease and investigate the impact of patient characteristics on overall image quality. 

140 14:51
Detection of myocardial infarcts without contrast agent injection: Comparison of spin-lock with magnetization transfer MR imaging
Joep van Oorschot1, Martijn Froeling1, Thijs van den Broek2, Frebus van Slochteren2, Steven Chamuleau2, Peter Luijten1, Tim Leiner1, and Jaco Zwanenburg1

1Radiology, University Medical Center Utrecht, Utrecht, Netherlands, 2Cardiology, University Medical Center Utrecht, Utrecht, Netherlands

Two promising techniques for endogenous myocardial infarct detection are Magnetization Transfer  and T1ρ-MRI. Goal of the study was to compare the ability to detect and quantify myocardial scar tissue in a chronic infarct model using MT and T1ρ mapping. In vivo MRI was performed on a clinical 1.5 MR scanner in 3 anesthetized pigs, 4 weeks after 90 minutes occlusion of the LAD. The MTR was significantly lower in the infarcted region (0.27±0.01 ms), compared to remote myocardium (0.38±0.01 ms).The T1ρ relaxation time was significantly higher in the infarcted region (87.0±1 ms), compared to healthy remote myocardium (56.4± 1 ms).

141 15:03
Free-breathing 3D late gadolinium enhancement cardiovascular magnetic resonance using outer volume suppressed projection navigators: Development and clinical validation
Rajiv G Menon1, G Wilson Miller2, Jean Jeudy1, Sanjay Rajagopalan3, and Taehoon Shin1

1Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, Baltimore, MD, United States, 2Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, United States, 3Division of Cardiovascular Medicine, University of Maryland, Baltimore, Baltimore, MD, United States

We developed a free-breathing, 3D late gadolinium enhancement (FB 3D-LGE) cardiovascular magnetic resonance  technique based on outer volume suppressed 1D-projection navigators and a stack-of-spirals acquisition. The free-breathing 3D-LGE and conventional breath-hold 2D-LGE scans were performed on 29 cardiac patients. 2D and 3D techniques showed no significant differences in overall image quality scores and image artifact scores (P  >  0.1). There was a significant correlation in the average difference in fractional scar volume (r=0.96). The FB 3D-LGE is a viable option for patients, particularly in acute settings or in patients who are unable to comply with breath-hold instructions.

142 15:15
Cardiac 31P MRS in breast cancer patients undergoing chemotherapy
Gillian Macnaught1,2, Christopher Rodgers3, Martin Denvir4, Olga Oikonomidou5,6, Annette Cooper1, William Clarke3, Heather McVicars6, Larry Hayward6, Saeed Mirsadraee1, and Scott Semple1,4

1Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, United Kingdom, 2the MRC Centre for inflammation Research, University of Edinburgh, Edinburgh, United Kingdom, 3RDM Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, 4BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom, 5Edinburgh Cancer Research Centre, University of Edinburgh, Edinburgh, United Kingdom, 6Edinburgh Cancer Centre, NHS Lothian, Edinburgh, United Kingdom

Anthracyclines are chemotherapy agents widely used to treat cancer but that can also induce cardiotoxicity. Techniques are required to provide an earlier warning of cardiotoxicity before irreversible myocardial damage. 9 subjects were recruited to this on-going 31P MRS study to detect changes in cardiac energetics of breast cancer patients undergoing chemotherapy. Between pre- and mid-chemotherapy four subjects experienced a greater than 20% decrease in their cardiac PCr/ATP ratio, 1 subject experienced a 13.8% decrease in left ventricular ejection fraction (LVEF) and all had increased troponin levels. Ultimately this study aims to determine whether changes in PCr/ATP precede changes in LVEF.

143 15:27
Significant improvement of survival by T2* MRI in thalassemia major
Antonella Meloni1, Caterina Borgna-Pignatti2, Giovanni Carlo Del Vecchio3, Maria Antonietta Romeo4, Maria Rita Gamberini5, Federico Bonetti6, Maria Giovanna Neri1, Elisabetta Chiodi7, Vincenzo Positano1, and Alessia Pepe1

1Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy, 2Università di Ferrara, Ferrara, Italy, 3Uiversity of Bari, Bari, Italy, 4University of Catania, Catania, Italy, 5Arcispedale "S.Anna", Ferrara, Italy, 6Policlinic Foundation San Matteo IRCCS, Pavia, Italy, 7Arcispedale “S. Anna”, Ferrara, Italy

The introduction of T2* CMR for the reproducible and non-invasive assessment of myocardial iron overload reduced the likelihood of developing decompensated cardiac failure, allowing the reduction of cardiac mortality in chronically transfused TM patients

144 15:39
Elevated Hemoglobin A1c(HbA1c) Is Independently Associated with Large Lipid-Rich Necrotic Cores in Hypertensive Patients with Symptomatic Carotid Atherosclerosis: A 3.0T MRI Study
Huilin Zhao1, Beibei Sun1, Xiaosheng Liu1, Xihai Zhao2, Yongming Dai3, Chun Yuan4, and Jianrong Xu1

1Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China, People's Republic of, 2Center for Biomedical Imaging Research, Tsinghua University School of Medicine, Beijing, China, People's Republic of, 3Philips Healthcare, Shanghai, China, People's Republic of, 4Radiology, University of Washington, Seattle, WA, United States

Further understanding of the association of hemoglobin A1c(HbA1c) levels with symptomatic carotid plaque characteristics will be helpful for stroke risk stratification and treatment strategy modification. This study sought to investigate the associations of HbA1c levels with MR-identified carotid plaque characteristics in hypertensive patients with acute stroke. Our key findings are that elevated HbA1c was associated with carotid plaque presence, higher HbA1c level tended to exhibit an increased plaque burden and larger lipid-rich necrotic core, independent of other cardiovascular risk factors. Our findings indicate that elevated HbA1c may contribute to the development of advanced carotid plaques in stroke patients with hypertension.

145 15:51
Cardiac Magnetic Resonance detects an association between aortic stiffness and epicardial fat volume in patients with increased cardiovascular risk
Rami Homsi1, Alois Martin Sprinkart1, Jürgen Gieseke1,2, Julian Luetkens1, Michael Meier-Schroers1, Darius Dabir1, Daniel Kuetting1, Christian Marx1, Hans Schild1, and Daniel Thomas1

1Radiology, University Hospital Bonn, Bonn, Germany, 2Philips Healthcare, Hamburg, Germany

In a Cardiac Magnetic Resonance based approach the study reveals a relationship between epicardial fat and aortic stiffness which are both associated with cardiovascular risk and disease.

146 16:03
Intradialytic MRI for the assessment of Cardiovascular Function
Charlotte E Buchanan1,2, Azharuddin Mohammed2, Eleanor F Cox1, Maarten W Taal2, Nicholas M Selby2, Susan T Francis1, and Christopher W McIntyre3

1Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 2Division of Medical Sciences and Graduate Entry Medicine, University of Nottingham, Nottingham, United Kingdom, 3Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada

We perform the first study of intradialytic MRI to assess cardiovascular stress during dialysis. A significant reduction in cardiac output (CO), stroke volume (SV) and IVC flux was seen during dialysis. Myocardial strain measures revealed significant stunned segments in the long axis in all individuals. No significant change in coronary artery flow was evident, and both myocardial perfusion and T1 measures in a single short axis slice showed no significant change. The change in CO and SV was negatively correlated with dialysis ultrafiltration volume. This work demonstrates MRI can be used to assess cardiac stress during dialysis.


Oral

Dementia: Alzheimer's Disease

Hall 606 14:15 - 16:15 Moderators:Ellen Ackerstaff & Ganesh Adluru

147 14:15
MR Elastography Demonstrates Unique Regional Brain Stiffness Patterns in Dementias
Mona ElSheikh1, Arvin Arani1, Avital Perry2, Nealey Cray2, Fredric Meyer2, David Lake1, Armando Manduca3, Kevin Glaser1, Richard L Ehman1, and John Huston1

1Radiology, Mayo Clinic, Rochester, MN, United States, 2Neurosurgery, Mayo Clinic, Rochester, MN, United States, 3Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States

The development of advanced MRI techniques has enabled noninvasive evaluation of subtle changes of brain architecture in dementia. We report a specific pattern of regional brain stiffness changes using Magnetic Resonance Elastography (MRE) in three different dementia groups: Alzheimer’s disease, frontotemporal dementia, and normal pressure hydrocephalus. MRE offers a potential biomarker to characterize the viscoelastic properties of the brain in dementia patients, and may have a role in the diagnosis and differentiation between common subtypes of dementia.


148
14:27
High resolution MR elastography of the hippocampus reveals differential tissue elasticity in Alzheimer's disease – a pilot study
Andreas Fehlner1, Lea M Gerischer2, Agnes Flöel2,3, Jürgen Braun4, and Ingolf Sack1

1Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany, 2Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany, 3NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany, 4Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Berlin, Germany

Multifrequency MR elastography (MMRE) was applied to 14 patients with Alzheimer's disease (AD) and compared to 14 age matched asymptomatic controls. We observed a marked decrease of the white-matter complex shear modulus |G*| in patients with AD. This reduction in |G*| was even more pronounced in the hippocampal region. In this region a diagnostic performance of 78% sensitivity and 92% specificity (AUROC-value 0.918) was obtained based on a viscoelasticity cutoff value of 0.9 kPa. In the future MMRE-measured |G*| could serve as a quantitative imaging marker for early diagnosis and progression monitoring of AD.

149 14:39
1H-[13C]-NMR Investigation of Neuroprotective Action of Ayurvedic Formulation in AβPP-PS1 Mouse Model of Alzheimer’s Disease
Kamal Saba1, Niharika Rajnala1, and Anant Bahadur Patel1

1NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India

Alzheimer's disease (AD) is a progressive neurodegenerative disorder. Currently no definite treatment available for AD. We have examined the efficacy of Rasa Sindoor, an Ayurvedic formulation, for the improvement of memory and neuronal activity in AβPP-PS1 mouse model of AD. Neuronal metabolism was followed by 1H-[13C]-NMR spectroscopy together with an infusion of [1,6-13C2]glucose. Our results indicate that the Rasa-Sindoor improved memory, and excitatory and inhibitory neuronal metabolic activity in AD mice.

150
14:51
Brain phospholipid and energy metabolism in mild Alzheimer’s disease and healthy aging: a 31P Magnetic Resonance Spectroscopy study
Anne Rijpma1,2, Marinette van der Graaf3,4, Olga Meulenbroek1,2, Marcel Olde Rikkert1,2, and Arend Heerschap3

1Geriatric Medicine, Radboud university medical center, Nijmegen, Netherlands, 2Radboud Alzheimer Centre, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, Netherlands, 3Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, Netherlands, 4Paediatrics, Radboud university medical center, Nijmegen, Netherlands

In this study we assessed phospholipid and energy metabolism in patients with mild Alzheimer’s disease and healthy age-matched control subjects by 3D 31P MRS imaging. Four brain regions were investigated: left and right hippocampus, anterior cingulate cortex, and retrosplenial cortex. Disease specific differences as well as differences between brain regions were found. 

151
15:03
4D Flow MRI for assessing flow pulsatility along the carotid siphon in Alzheimer’s disease
Leonardo A Rivera-Rivera1, Tilman Schubert2, Kevin M Johnson1, Sterling C Johnson3, Oliver Wieben1,2, and Patrick Turski2

1Medical Physics, University of Wisconsin Madison, Madison, WI, United States, 2Radiology, University of Wisconsin Madison, Madison, WI, United States, 3Medicine, University of Wisconsin Madison, Madison, WI, United States

Cerebral arteries are often morphologically altered and dysfunctional in Alzheimer’s disease (AD). In this study, 4D flow MRI was used to assess flow pulsatility along the carotid siphon in patients with AD, mild cognitive impairment (MCI) and in healthy age matched controls. We found the physiologic dampening of pulsatility along the distal ICA is significantly diminished in patients with AD. With the large volume coverage and high temporal and spatial resolution, 4D flow MRI can provide additional biomarkers of vascular health that can contribute to the identifying patients who could benefit from interventions to improve circulatory system functions.

152 15:15
In Vivo Visualization of Iron-Rich Amyloid Plaques In Cholesterol-Fed Rabbits using Clinical Field-Strength Magnetic Resonance Imaging
Yuanxin Chen1, Yong Wang1,2, Kem A Rogers1, John A Ronald1, and Brian K Rutt3

1Western University, London, ON, Canada, 2Lawson Health Research Institute, London, ON, Canada, 3Stanford University, Stanford, CA, United States

Hypercholesterolemia is a risk factor for AD and promotes increased production of beta-amyloid protein. Our lab has developed a rabbit model of AD by enriching the diets of rabbits with low amounts of cholesterol. In this study, we combined this cholesterol-fed rabbit model of AD with iron-sensitive, high-resolution MRI and demonstrated non-invasive in vivo visualization of AD plaques throughout the brains of these animals. The imaging techniques have been developed and optimized using a clinical field strength scanner (3T), which is an important step towards clinical application in human AD patients.  

153
15:27
Latent Atrophy Factors in Alzheimer's Disease
Xiuming Zhang1, Elizabeth C. Mormino2, Reisa A. Sperling2, Mert R. Sabuncu3,4, and B.T. Thomas Yeo1,3,5

1ASTAR-NUS Clinical Imaging Research Centre, Department of Electrical and Computer Engineering, Singapore Institute for Neurotechnology and Memory Networks Program, National University of Singapore, Singapore, Singapore, 2Department of Neurology, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, United States, 3Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, United States, 4Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, United States, 5Centre for Cognitive Neuroscience, Duke-NUS Graduate Medical School, Singapore, Singapore

Alzheimer's disease (AD) is the most common form of dementia and greatly heterogeneous. Here we develop a model of the heterogeneity of AD-related atrophy, demonstrating that most AD dementia patients and at-risk nondemented participants express multiple latent atrophy factors to varying degrees. Our study also demonstrates that these atrophy factors are associated with distinct cognitive decline trajectories across the preclinical and clinical stages. Our results provide a framework by which biomarker readouts could potentially predict disease progression at the individual level. Our analytic strategy is general and might be utilized to discover subtypes within and across other heterogeneous brain disorders.

154 15:39
Association of Alzheimer’s disease GWAS loci with default mode network
fan su1

1southeast university, nanjing, China, People's Republic of

To investigate the altered pattern of DMN in amnestic mild cognitive impairment (aMCI) subjects and the genetic factors that lead to the DMN dysfunctions, 87 individuals with aMCI and 131 matched healthy controls were recruited and an average 3-year follow-up study was performed. We studied the differences of DMN between aMCI subjects and healthy controls at baseline and how the DMN changed over time. Regression analyses were performed to explore whether the GRS influence the DMN dysfunctions. We observed that DMN disengage in the early stage of AD and the combined effect of AD-related loci influence the DMN pattern.

155 15:51
The effect of Alzheimer's disease on the viscoelasticity of the mouse brain under the influence of enriched environment.
Jing Guo1, Tonia Munder2, Charlotte Klein2, Anna Pfeffer2, Jürgen Braun3, Barbara Steiner2, and Ingolf Sack1

1Department of Radiology, Charité - University Medicine Berlin, Berlin, Germany, 2Department of Neurology, Charité - University Medicine Berlin, Berlin, Germany, 3Institute of Medical Informatics, Charité - University Medicine Berlin, Berlin, Germany

MRE was used to study environmental influences on viscoelasticity of the murine hippocampus in Alzheimer's disease (AD). In wild type control mice, hippocampal viscosity was significantly increased within 6 months while elasticity remained unchanged. This suggests that environment-stimulated neuronal proliferation adds mobile elements to the mechanical matrix of the brain which increases mechanical attenuation properties. Within 6 months, AD caused a decline of hippocampal viscosity only in the enriched environment while standard mouse remained unaffected suggesting that AD in an early phase primarily affects new neurons in the murine hippocampus.

156 16:03
A preliminary study on MR amide proton imaging in patients with Alzheimer’s disease and mild cognitive impairment
Rui Wang1, Chunmei Li1, Yongming Dai2, Dantao Peng3, Xuna Zhao4, and Min Chen1

1Radiology, Beijing Hospital, Beijing, China, People's Republic of, 2Philips Heathcare, Shanghai, China, People's Republic of, 3China-Japan Friendship Hospital, Beijing, China, People's Republic of, 4Philips Heathcare, Beijing, China, People's Republic of

The aim of this study is to evaluate the feasibility of MR amide proton transfer (APT) imaging for the detection of cerebral abnormalities in patients with Alzheimer’s disease (AD) and amnestic mild cognitive impairment (aMCI), and to explore its clinical utility. Twenty-one AD patients, 11 aMCI patients and 19 normal controls (NC) underwent APT MR imaging. The magnetic resonance ratio asymmetry (MTRasym) values at 3.5ppm of bilateral hippocampi, temporal white matter regions, occipital white matter regions and cerebral peduncles were measured on the oblique APT images. We found that MTRasym(3.5ppm)asym in bilateral hippocampi showed a consistently increasing trend from NC to MCI, to AD. MTRasym(3.5ppm) values of bilateral hippocampi were significantly negatively correlated with MMSE. Our results suggested that APT imaging is a useful tool to diagnose early AD and monitor the disease. 


Oral

Hepatobiliary 1: Liver Perfusion/Flow & Function

Summit 1 14:15 - 16:15 Moderators:Scott Reeder & Alejandro Roldán-Alzate

157
14:15
MR elastography and DCE-MRI of the liver and spleen for non-invasive prediction of portal pressure
Stefanie Hectors1, Mathilde Wagner1, Octavia Bane1, Aaron Fischman2, Thomas Schiano3, and Bachir Taouli1,4

1Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2Department of Interventional Radiology, Icahn School of Medicine at Mount SInai, New York, NY, United States, 3Department of Internal Medicine, Icahn School of Medicine at Mount SInai, New York, NY, United States, 4Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States

The goal of this study was to assess whether DCE-MRI parameters and MR elastography-derived stiffness in liver and spleen can predict portal pressure. Liver time-to-peak (TTP), mean transit time (MTT), upslope and stiffness (LS) all significantly correlated with hepatic venous pressure gradient (HVPG) measurement. Sensitivity-specificity of LS for detection of HVPG≥5mmHg and HVPG≥10mmHg were 64%-91% and 71%-89% respectively, while combined LS and spleen TTP yielded the highest sensitivity-specificity (92%-86% for HVPG≥5mmHg, 100%-92% for HVPG≥10mmHg). These results indicate that combination of liver and spleen perfusion and stiffness metrics into a multiparametric analysis maximizes diagnostic performance for the prediction of portal pressure.

158
14:27
Longitudinal assessment of structural and haemodynamic parameters in compensated cirrhosis using Quantitative Magnetic Resonance Imaging
Chris Bradley1, Eleanor F Cox1, David Harman2, Martin W James2, Guru P Aithal2, I Neil Guha2, and Susan T Francis1

1Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom, 2NIHR Biomedical Research Unit in Gastrointestinal and Liver Diseases, University of Nottingham, Nottingham, United Kingdom

We perform a longitudinal 3 year study to assess progression of disease in compensated cirrhosis (CC) using annual haemodynamic and structural MR measures, and compare with a healthy volunteer group. Longitudinal relaxation time (T1) correlates with liver disease severity, and shows a small variance across years in stable, compensated cirrhosis. In contrast a large variance is shown for liver stiffness measures using Fibroscan®. MR measures correlate well with Enhanced Liver Fibrosis (ELF) scores. This study suggests that MR provides a sensitive technique to assess changes in pathophysiology of CC.

159 14:39
Hemodynamic Changes in the Portal Circulation in Living Related Liver Donors, Assessed by 4D flow MRI
Alejandro Roldán-Alzate1,2, Luis A Fernandez3, Oliver Wieben2,4, and Scott B Reeder2,4

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

The purpose of this study was to evaluate hemodynamic changes in the mesenteric and portal circulation of LDLT donors in response to surgical liver resection. Four living related liver donors were studied. Subjects were imaged using 4D Flow MRI before and after liver resection surgery. Highly patient-specific responses to each surgical procedure were found. The ability to quantify hemodynamic changes in the portal and mesenteric circulation non-invasively demonstrates that 4D flow MRI may be a suitable tool for both surgical planning of LDLT, and for improved understanding of the hemodynamic changes that occur in the liver remnant of the donor.

160
14:51
Free-Breathing 3D Liver Perfusion Quantification Using a Dual-Input Two-Compartment Model
Satyam Ghodasara1, Vikas Gulani2, and Yong Chen2

1Case Western Reserve University School of Medicine, Cleveland, OH, United States, 2Radiology, Case Western Reserve University, Cleveland, OH, United States

The dual-input two-compartment model was applied to liver perfusion data, and significant differences in perfusion parameters were found between normal hepatic parenchyma and focal lesions, and also between HCC and metastatic lesions. These findings support the possibility of using a two-compartment model with 3D free-breathing acquisitions, for lesion characterization.

161 15:03
Acceleration of Image Analysis for Liver Perfusion Quantification Using Parallel Computational Techniques
Satyam Ghodasara1, Yong Chen2, Mark Griswold2, Nicole Seiberlich3, and Vikas Gulani2

1Case Western Reserve University School of Medicine, Cleveland, OH, United States, 2Radiology, Case Western Reserve University, Cleveland, OH, United States, 3Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States

To make free-breathing liver perfusion quantification feasible for a clinical timescale, acceleration of both non-Cartesian parallel imaging reconstruction and non-rigid image registration was performed with parallel computing techniques. Our results show massively increased speed (12 minutes compared to >22.5 hours for standard computations) with extremely minor differences in both image quality and perfusion quantification.

162
15:15
Measurement of bulk liver perfusion: Assessment of agreement between ASL and caval subtraction phase-contrast MRI at 9.4T
Manil Chouhan1, Rajiv Ramasawmy2, Alan Bainbridge3, Adrienne Campbell-Washburn2, Jack Wells2, Shonit Punwani1, Rajeshwar Mookerjee4, Simon Walker-Samuel2, Mark Lythgoe2, and Stuart Taylor1

1UCL Centre for Medical Imaging, University College London, London, United Kingdom, 2UCL Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom, 3Department of Medical Physics, University College London Hospitals NHS Trust, London, United Kingdom, 4UCL Institute for Liver and Digestive Health, University College London, London, United Kingdom

Non-invasive preclinical liver perfusion measurements could be used to develop biomarkers and assess new treatments for liver disease and primary/secondary malignant liver lesions.  ASL can provide regional hepatic perfusion maps, and in this study we compare FAIR ASL tissue perfusion measurements with caval subtraction phase-contrast MRI, a validated method for measuring total liver blood flow, to demonstrate ASL overestimation but encouraging agreement between both methods.

163 15:27
Quantitative Liver Function Analysis using Volumetric T1 Mapping with Fast Multi-Slice B1 Correction on Hepatocyte-specific Contrast Enhanced Liver Magnetic Resonance Imaging
Jeong Hee Yoon1, Jeong Min Lee1, Eun Ju Kim2, Tomoyuki Okuaki3, and Joon Koo Han1

1Radiology, Seoul National University Hospital, Seoul, Korea, Republic of, 2Philips Healthcare, Seoul, Korea, Republic of, 3Philips Healthcare, Tokyo, Japan

Liver signal intensity on hepatobiliary phase at gadoxetic acid-enhanced liver MRI has been reported to be useful to estimate global and regional liver function quantitatively. However, simple MR signal measurement is often suffering from its sensitivity of MR field inhomogeneity and non-linear relationship with contrast medium concentration. Herein, we investigated of B1 correction effect on T1 map and compared its diagnostic performance to assess liver function according to Child-Pugh classification. In addition, we attempted to investigate risk assessment capability of B1 corrected T1 map for long-term clinical outcome in patients with cirrhosis.

164 15:39
Gd-EOB-DTPA-enhanced MRI: evaluation of liver function by multiple hepatocyte-phase images and T1 mapping in rats
Jia Xu1, Xuan Wang1, Yan You2, Qin Wang1, Hui Liu3, Jing Lei1, Huadan Xue1, and Zhengyu Jin1

1Department of Radiology, Peking Union Medical College Hospital, Beijing, China, People's Republic of, 2Department of Pathology, Peking Union Medical College Hospital, Beijing, China, People's Republic of, 3Siemens Ltd. China, Shanghai, China, People's Republic of

To evaluate regional liver function preoperatively is of great value in planning surgical management. Our Aim is to investigate the potential of Gd-EOB-DTPA enhanced MRI in evaluating hepatic function in rats with liver fibrosis. Parameters calculated from Gd-EOB-DTPA enhanced MRI exhibited moderate to high correlation with plasma indocyanine green retention rate at 15 minutes after intravenous injection of ICG (ICG R15) in rats with liver fibrosis, indicating its potential in liver function evaluation. 

165 15:51
Comparison of the Hepatocyte Fraction and Conventional Image Based Methods for the Estimation of Liver Function
Tomoyuki Okuaki1, Kosuke Morita2, Tomohiro Namimoto3, Morikatsu Yoshida3, Shinya Shiraishi3, Masanori Komi2, Yasuyuki Yamashita3, and Marc Van Cauteren1

1Philips Healthcare, Tokyo, Japan, 2Department of Central Radiology, Kumamoto University Hospital, Kumamoto, Japan, 3Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan

The hepatocyte fraction (HeF) is based on simple pharmacokinetics, and can quantitatively estimate the fraction of hepatocytes. In this study, the HeF, liver-spleen contrast ratio and delta T1 value were compared to the results of 99mTc-GSA scintigraphy using the blood clearance index (HH15) and receptor index (LHL15). The correlation coefficients of the HH15 were 0.602, 0.544 and 0.773, respectively, and of the LHL15 were 0.612, 0.670 and 0.762, respectively. The HeF quantification showed the highest correlation with the 99mTc-GSA, proving it to be useful for a robust evaluation of liver function, compared to conventional imaging based quantitative methods.

166 16:03
The change and interrelation of quantitative hepatic MR imaging biomarkers in the course of chronic hepatitis.
Akira Yamada1, Yasunari Fujinaga1, Yoshihiro Kitoh2, Takeshi Suzuki1, Daisuke Komatsu1, Aya Shiobara2, Yasuo Adachi2, Atsushi Nozaki3, Yuji Iwadate3, Kazuhiko Ueda1, and Masumi Kadoya1

1Department of Radiology, Shinshu University School of Medicine, Matsumoto, Japan, 2Division of Radiology, Shinshu University Hospital, Matsumoto, Japan, 3GE Healthcare Japan, Hino, Japan

Variable quantitative hepatic imaging biomarkers including pharmacokinetic parameters of hemodynamics and hepatocellular uptake function, R2* and fat fraction, apparent diffusion coefficient (ADC), liver stiffness were obtained from the patients with chronic hepatitis using MR imaging. The change and interrelation of these imaging biomarkers in the course of chronic hepatitis were evaluated quantitatively. Portal venous inflow and hepatocellular uptake function correlated well with liver stiffness, meanwhile, ADC showed weak correlation. Arterial compensation, decreased blood flow speed and volume were observed in the patients with decreased portal venous inflow. No significant correlation was observed between liver stiffness and R2* or fat fraction.


Oral

RF Coil Arrays

Summit 2 14:15 - 16:15 Moderators:Randy Duensing & Fraser Robb

167 14:15
A 32-channel integrated body coil for 7 Tesla whole-body imaging
Stephan Orzada1, Andreas K. Bitz2, Oliver Kraff1, Mark Oehmigen1,3, Marcel Gratz1,3, Sören Johst1, Maximilian N. Völker1, Stefan H. G. Rietsch1,3, Martina Flöser2, Thomas Fiedler2, Samaneh Shooshtary4, Klaus Solbach4, Harald H. Quick1,3, and Mark E. Ladd1,2

1Erwin L. Hahn Institute for MRI, Essen, Germany, 2Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 3High Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany, 4High Frequency Technology, University of Duisburg-Essen, Duisburg, Germany

Due to the severe problems with B1 inhomogeneity, volume resonators are not a good choice for body applications at ultra-high fields, and local multi-channel arrays are commonly used for transmission. In this work we present an integrated 32ch transmit/receive body array for 7 Tesla whole-body imaging. First in vivo images show a human volunteer imaged completely in 4 stations.

168
14:27
Approaching the Ultimate Intrinsic SNR with Dense Arrays of Electric Dipole Antennas
Gang Chen1,2,3, Riccardo Lattanzi1,2, Daniel Sodickson1,2, and Graham Wiggins1,2

1The Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University School of Medicine, New York, NY, United States, 2The Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, United States, 3The Sackler Institute of Graduate Biomedical Science, New York University School of Medicine, New York, NY, United States

Coil designs motivated by the ideal current patterns corresponding to the Ultimate Intrinsic SNR (UISNR) have been used to boost central SNR at 3T and 7T. For a cylindrical phantom and a current distribution defined on a concentric cylindrical surface, the ideal current pattern for optimal central SNR includes both divergence-free and curl-free components. While loops are exclusively divergence-free, recent work has shown that electric dipole antennae include both divergence-free and curl-free current components. Here we explore in simulation whether arrays with an increasing number of electric dipole antennas can approach UISNR in the center of a head-sized phantom at 7T, and investigate selected practical design considerations.

169 14:39
Optimization of the Transceiver Phased Array for Human Brain Imaging at 9.4 T: Loop Overlapping Rediscovered.
Nikolai I Avdievich1, Ioannis Giapitzakis1, Andreas Pfrommer1, and Anke Henning1,2

1High-field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany, 2Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

Ultra-high field (UHF) (>7T) transmit (Tx) and transceiver surface loop phased arrays improve Tx-efficiency and homogeneity for human brain imaging. Overlapping the loops enhances Tx-efficiency and SNR by increasing the penetration depth. However, overlapping can compromise decoupling and SNR by generating a substantial mutual resistance. Therefore, UHF Tx-arrays are commonly constructed using gapped loops. Based on analytical optimization we constructed a 9.4T 8-loop head transceiver array. Both the magnetic and electric coupling were compensated at the same time by overlapping and excellent decoupling was obtained. Tx- and Rx-performance of the array was compared favorably to that of a gaped array.

170 14:51
Comparison of 3T whole body parallel transmit arrays based on measured data from full scale models
Eddy B Boskamp1, Saikat Saha1, Ricardo Becerra1, and Michael Edwards1

1Engineering, GE Healthcare, Waukesha, WI, United States

In this study we are comparing 16 channel TEM, 8 channel TEM and 8 loop array pTx body coils based on experimental data obtained from full scale whole body prototypes as opposed to only simulation. Besides SAR, efficiency and uniformity, there are additional criteria to include when selecting a body coil for parallel transmit. Examples are star intensity artifact, E fields that heat up cables and baluns, VSWR, and perturbation sensitivity, which may make it impossible to build a certain design given obtainable tolerances.

171 15:03
A 3D Loop-Loopole Receive  Array for Spine Imaging at 3.0 T.
Karthik Lakshmanan1,2, Ryan Brown1,2, and Graham C Wiggins1,2

1Center for Biomedical Imaging, Department of Radiology, NYU School of Medicine, Newyork, NY, United States, 2Center for Advanced Imaging Innovation and Research (CAI2R), NYU School of Medicine, Newyork, NY, United States

High channel count RF receive coil arrays have become commonplace due to the advent of parallel imaging techniques and due to technical advances in receive chain technology. Using these general purpose coil arrays SNR can be maximized over wide depths by covering the imaging region with an array of planar loops. This is usually achieved by reducing the coil dimensions while still maintaining sufficiently high unloaded-to-loaded Q ratio. In this work we aim to improve upon the SNR of a high element count array by adding concentric orthogonal "Loopole" elements. The asymmetric behavior of the loopoles combined with its orthogonal location provided SNR improvements both at shallow and deep regions in an imaging plane.

172 15:15
Detailing Local Multi-Channel RF Surface Coil versus Body RF Coil Transmission for Cardiac MRI at 3 Tesla: Which Configuration is Winning the Game?
Oliver Weinberger1,2, Lukas Winter1, Matthias A Dieringer1, Antje Els1, Celal Oezerdem1, Antonino Cassara3, Harald Pfeiffer3, and Thoralf Niendorf1,2

1Berlin Ultrahigh Field Facility (BUFF), Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany, 2Experimental and Clinical Research Center (ECRC), Charité Medical Faculty, Berlin, Germany, 3Physikalisch Technische Bundesanstalt (PTB), Berlin, Germany

In this work a local four-channel transmit/receive RF coil dedicated for cardiac MR at 3T is compared to a conventional built-in body RF coil in conjunction with a four-channel receive-only RF coil. SAR and B1+ simulations of both configurations are shown. The invivo efficiency performance of both coils in respect to B1+/sqrt(SAR) is demonstrated in 12 healthy subjects. The efficiency surplus of the local RF coil was used to increase the applicable flip angle FASSFP of a standard high resolution 2D SSFP protocol or to shorten the used repetition time TRSSFP by 54%.

173 15:27
Design of a 8-channel transceive dipole array with up to 64 receive-only loop coils
Ingmar Voogt1, Dennis W.J. Klomp1, Hans Hoogduin1, Peter R. Luijten1, Cornelis A.T. van den Berg1, and Alexander J.E. Raaijmakers1

1UMC Utrecht, Utrecht, Netherlands

We have developed an array combination consisting of eight fractionated dipole antennas combined with 64 receive loops. Loops are combined in 16 linear groups of four. Eight are equipped with a transmit dipole antenna, eight are not. The coupling between all elements is below -15 dB. The transmit efficiency is not influenced by the presence of the receive loops. Phantom MRI measurements show strong enhancement of the SNR. Finally, preliminary human scans (T2w images) have been acquired.

174
15:39
Parallel Transmit (pTx) Capability of Various RF Transmit Elements and Arrays at 7T UHF MRI
Stefan HG Rietsch1,2, Stephan Orzada1, and Harald H Quick1,2

1Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany, 2High Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany

First steps towards whole body imaging with remote arrays at 7T UHF MRI are currently undertaken. Parallel transmit (pTx) capabilities of transmit arrays can be evaluated by the number of degrees of freedom which characterize the shim capabilities. In this work, 16 different pTx arrays with different transmit elements and combinations of transmit elements are simulated to examine inter element coupling behavior, singular values to determine the degrees of freedom and shim capabilities. Combining dipoles and loops seems to be the most promising approach among the investigated pTx arrays.

175 15:51
About the Ultimate SNR for Cylindrical and Spherical RF Arrays in a Realistic Human Head Model
Andreas Pfrommer1 and Anke Henning1,2

1Max Planck Institute for Biological Cybernetics, Tuebingen, Germany, 2Institute for Biomedical Engineering, UZH and ETH Zurich, Zurich, Switzerland

In this work we investigated differences in the ultimate SNR in a realistic human head model for two configurations with the RF array elements distributed on either a cylindrical or a spherical holder. The basis set of solutions in our approach was created by vector cylindrical and spherical harmonics, which are known to form a complete set of eigenfunctions to Maxwell’s equations in free-space. Assuming both surfaces have the same radius, the spherical geometry yielded higher SNR in grey and white matter compared to the cylindrical one. Moreover it allowed higher acceleration factors with the same g-factors.

176 16:03
High-quality flexible printed MRI receive coils towards garment integration
Pierre Balthazar Lechene1, Joe Corea1, Anita Flynn1, Michael Lustig1, and Ana Arias1

1EECS, UC Berkeley, Berkeley, CA, United States

Close proximity of MRI receive coils to the patient can allow an increase of signal-to-noise ratio (SNR). Integrating the coils into garments that tightly conform to the body can provide such proximity. This work develops flexible printed MRI coils on a mesh with the potential to be integrated into garments. The dielectric used in the coil’s capacitors is optimized to provide SNR within 91% of conventional coils. Encapsulation enhances the coils mechanical robustness, allowing bending below 1mm of radius of curvature. It is shown that, by cutting and sewing, the coils can be tailored to intimately fit a brassiere cup.   


Combined Educational & Scientific Session

Ultrastructural & Functional Bone & Muscle Imaging

Organizers:Jenny T. Bencardino, M.D., Eric Y. Chang, M.D., Christine Chung, M.D., Ravinder R. Regatte, Ph.D., Philip Robinson, M.D. & Siegfried Trattnig, M.D.

Nicoll 1 14:15 - 16:15 Moderators:Mark Does & Jiang Du

14:15
Muscle Quality and Function
John Thornton1

1MRC Centre for Neuromuscular Diseases, University College London, London, United Kingdom

Target audience: This presentation is intended to inform those interested in the application of quantitative MRI to probe structure, function or pathology in skeletal muscle.    Objectives: To outline the properties of skeletal muscle pertinent to quantitative MRI, the various MRI-accessible quantities that reflect muscle quality, and how MRI measurements correlate with disease severity and functional assessment

14:45
Clinical Applications
Thomas M Link1

1Department of Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States

Over the past decade advanced quantitative MRI techniques have evolved which allow to characterize bone and muscle structure and function. Clinically applicable techniques analyzing bone quality and strength are high resolution, morphological MRI, UTE and MRS. These techniques have shown promise in clinical studies, providing information beyond bone mineral density, the current standard measurement. Novel technologies focusing on the assessment of muscle structure and function are chemical shift-based fat quantification techniques, MRS, T2 relaxation time measurements and BOLD MRI, all of which are also clinically applicable and were used in investigating pain syndromes and disorders of muscle function.   

177
15:15
Bound- and Pore-Water MRI of Cortical Bone in Osteoporotic Patients
Mary Kate Manhard1, S Bobo Tanner2, Daniel F Gochberg3, Jeffry S Nyman4, and Mark D Does1

1Biomedical Engineering, Vanderbilt University, Nashville, TN, United States, 2Department of Medicine, Vanderbilt University, Nashville, TN, United States, 3Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 4Department of Orthopaedics & Rehabilitation, Vanderbilt University, Nashville, TN, United States

Osteoporotic fractures are a growing problem, and X-ray based methods do not always identify individuals at risk of a fracture. MRI based methods of bound and pore water in cortical bone have the potential to offer new information about fracture resistance. These methods were implemented on both osteoporotic volunteers and healthy controls in the tibia. Osteoporotic subjects had significant decreases in bound water concentration and slight increases in pore water concentration compared to healthy subjects. These promising results will allow for further investigation of changes of bound and pore water concentrations across diseases and with response to various treatment methods. 

178
15:27
Magnetic resonance elastography characterization of skeletal muscle stiffness changes resulting from pressure ulcers
Jules Laurent Nelissen1,2, Willeke Traa3, Larry de Graaf1, Kevin Moerman4, Cees Oomens3, Aart Nederveen5, Ralph Sinkus6, Klaas Nicolay1, and Gustav Strijkers2

1Biomedical NMR, Eindhoven University of Technology, Eindhoven, Netherlands, 2Preclinical and Translational MRI, Academic Medical Center, Amsterdam, Netherlands, 3Biomechanics of Soft Tissues, Eindhoven University of Technology, Eindhoven, Netherlands, 4MIT media lab, Massachusetts Institute of Technology, Cambridge, MA, United States, 5Radiology, Academic Medical Center, Amsterdam, Netherlands, 6Imaging Sciences & Biomedical Engineering, King's College London, London, United Kingdom

We have investigated the feasibility of using Magnetic Resonance Elastography (MRE) to quantify muscle-tissue mechanical properties and changes therein related to the development of deep tissue injury type of pressure ulcers. MRE measurements were performed before and after damage-inducing indentation of the tibialis-anterior muscle of Sprague Dawley rats. Current study demonstrates that changes in muscle-tissue mechanical properties associated with deep tissue injury can be quantified by MRE. We expect that better knowledge of changes in soft tissue mechanical properties due to damage, measured with MRE, will provide new insights in the aetiology of deep tissue injury and other muscle pathologies.

179
15:39
Selective in Vivo Bone Imaging with Long-T2 suppressed PETRA MRI
Cheng Li1, Jeremy F. Magland1, Xia Zhao1, Alan C. Seifert2, and Felix W. Wehrli1

1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States

An IR-based long-T2 suppressed PETRA sequence was designed and optimized to image sub-millisecond-T2 tissue components, e.g. collagen-bound bone water. To minimize scan time signal was sampled repeatedly after each inversion with individual excitation flip-angle designed to yield constant short-T2 signal amplitude. A fast non-iterative reconstruction algorithm combined with phase-modulated excitation pulse was applied to minimize image artifacts due to non-uniform excitation profile, allowing for increased flip-angle and higher SNR. Optimized long-T2 suppressed PETRA allows imaging of bone matrix water, opening up new possibilities for anatomic bone imaging at isotropic resolution and quantification in clinically practical scan times.

180 15:51
In vivo skeletal muscle fiber length measurements using a novel MRI diffusion tensor imaging approach: reproducibility and sensitivity to passive stretch.
Jos Oudeman1, Valentina Mazzoli1,2,3, Marco A Marra2, Klaas Nicolay3, Mario Maas1, Nico Verdonschot2, Andre M Sprengers2, Aart J Nederveen1, Gustav J Strijkers4, and Martijn Froeling5

1Radiology, Academic Medical Center, Amsterdam, Netherlands, 2Orthopedic Research Lab, Radboud UMC, Nijmegen, Netherlands, 3Biomedical NMR, Eindhoven University of Technology, Eindhoven, Netherlands, 4Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, Netherlands, 5Radiology, University Medical Center, Utrecht, Utrecht, Netherlands

Diffusion Tensor Imaging in combination with tractography facilitates 3D visualizations of the muscle architecture, which is described by fiber length and pennation angle. In order to get accurate fiber length estimation, tendinous structures need to be separated from muscles. In this work we propose a new method for semiautomatic tendon segmentation. The fiber length obtained after tendon segmentation is seen to be reproducible. Furthermore the sensitivity of the method allows for detection of change in fiber length whit muscle stretch. The observed behavior is in agreement with the known antagonistic function of muscles.

181
16:03
31P-MRS and MRI of lower leg muscle oxidative metabolism in heart failure patients
Ding Xia1, Stuart D. Katz2, and Ravinder R. Regatte1

1Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY, United States, 2Division of Cardiology, Department of Medicine, New York University Langone Medical Center, New York, NY, United States

We measured the lower leg muscle oxidative metabolism in healthy volunteers (n=5) and heart failure patients (n=6) with quantitative 31P-MRS and MRI at 3T clinical scanner. The post-exercise rate of phosphocreatine (PCr) resynthesis was decreased in heart failure subjects (i.e. delayed PCr recovery time) compared to healthy volunteers in global calf muscle, as well as in predominantly fast twitch (type II) gastrocnemius muscle (medial and lateral, GM and GL) and predominantly slow twitch (type I) soleus (SOL) muscle.

16:15
Adjournment & Meet the Teachers


Educational Course

Updates From Big Data Initiatives

Organizers:Jonathan Gillard, M.D., FRCR, MBA & Jennifer A McNab, Ph.D.

Nicoll 2 14:15 - 16:15 Moderators:James Gee & Jennifer McNab

14:15
Big Data: The Rhineland Study
Tony Stöcker1

11German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany

This lecture briefly introduces the Rhineland Study and summarizes the concepts of its MR protocol. The Rhineland Study investigates aging, in particular of the human brain and related neurological disorders, across the adult lifespan. The Rhineland Study will include up to 30,000 subjects, aged 30 years or over at first visit, and reexamination every three years. The emphasis is on quantitative measures, including one-hour MRI examination of brain structure and function.

14:45
Big Data: UK Biobank
Stephen Smith

I will give an overview of the UK Biobank brain imaging component, which will carry out multimodal brain imaging on 100,000 subjects as part of the UK Biobank long-term prospective epidemiological study. UK Biobank data is open access.

15:15
Big Data: Human Connectome Project
Bruce R. Rosen1

1Radiology, Massachusetts General Hospital, Charlestown, MA, United States


15:45
The Baseline Study of Human Health and the Transition to Illness
Sanjiv Gambhir1

1Radiology, Stanford University, Stanford, CA, United States


16:15
Adjournment & Meet the Teachers


Educational Course

ISMRM/SMRT Joint Forum: Update on MRI Contrast Agents - Recent Controversies

Organizers:Chris Kokkinos, B.App.Sc., Pg.Cert.(MRI) & Scott B. Reeder, M.D., Ph.D.

Nicoll 3 14:15 - 16:15 Moderators:Jeffrey Weinreb

14:15
Update on Nephrogenic Systemic Fibrosis: Should We Stop Screening?
Sadhana Nandwana

This presentation will provide a current update on nephrogenic systemic fibrosis (NSF) and where we stand with exposure of selected gadolinium based contrast agents (GBCAs) in renally impaired patients and risk of NSF. Risk stratification based on safety profiles of GBCAs and current national and international guidelines and recommendations will be examined. Evaluation of whether these guidelines should be modified in light of recent publications demonstrating a lack of NSF occurrence in patients exposed to specific GBCAs will be discussed. 

14:45
Panel Discussion

15:15
Gadolinium Deposition: Imaging Phenomenon or Should We Change Our Practice?
Greg C. Brown1

1Centre for Advanced Imaging, The University of Queensland, St Lucia, Australia

Reports of gadolinium accumulation in the brain have surprised many practitioners, and raised questions of potential harm to patients. The FDA & NIH recommend reconsideration of GBCA use while investigations continues. The accumulation calls into doubt a common assumption that existing renal function mediated guidelines are sufficient to avoid significant biological interaction.

This presentation reviews the recent reports and presents literature concerning gadolinium chelate stability, transmetalation, gadolinium interactions in biochemistry, observations of bone and skin accumulation (beyond NSF definitions), and environmental build up to provide a context for a reconsideration  by clinical and research practitioners of our current GBCA usage.


15:45
Panel Discussion

16:15
Ferumoxytol: Should We Be Using It in Clinical Practice?
Mustafa Bashir1

1Duke University Medical Center

Ferumoxytol has seen increasing use as a contrast agent in both clinical and research MRI.  This talk will describe some of the potential uses and risks associated with the agent.

16:45
Panel Discussion

17:15
Adjournment & Meet the Teachers


Traditional Poster : Contrast Mechanisms

Exhibition Hall 16:30 - 18:30 (no CME credit)

Electronic Poster : Diffusion

Exhibition Hall 16:30 - 17:30 (no CME credit)

Electronic Poster : CV

Exhibition Hall 17:30 - 18:30 (no CME credit)

Study Groups

High Field Systems & Applications; MR Safety

Hall 405 E 16:30 - 18:30


Study Groups

Hyperpolarized Media

Hall 406 D 16:30 - 18:30


Power Pitch

At the Cutting-Edge of Cancer Imaging

Power Pitch Theatre, Exhibition Hall 16:30 - 17:30 Moderators:Sungheon Gene Kim & Linda Moy

182
16:30
Immune co-stimulatory blockade permits human glioblastoma xenografting in immunocompetent mice: model validation with MRI and bioluminescence imaging
Samantha Lynn Semenkow1, Shen Li2, Eric Raabe1,3, Jiadi Xu2,4, Miroslaw Janowski2,5, Byoung Chol Oh6, Gerald Brandacher6, Jeff W. Bulte2,4, Charles Eberhart1,3,7, and Piotr Walczak2

1Department of Pathology, Johns Hopkins Medical Institue, Baltimore, MD, United States, 2Department of Radiology and Radiological Science, Johns Hopkins Medical Institue, Baltimore, MD, United States, 3Department of Oncology, Johns Hopkins Medical Institue, Baltimore, MD, United States, 4F. M. Kirby Center for Functional Brain Imaging Kennedy Krieger Institute, Johns Hopkins Medical Institue, Baltimore, MD, United States, 5NeuroRepair Department, Mossakowski Medical Research Centre, Warsaw, Poland, 6Department of Plastic and Reconstructive Surgery, Vascularized Composite Allotransplantation (VCA) Laboratory, Johns Hopkins Medical Institue, Baltimore, MD, United States, 7Department of Opthalmology, Johns Hopkins Medical Institue, Baltimore, MD, United States

183
16:33
In vivo 1H MRS and MRI longitudinal assessment of GBM mouse xenografts derived from freshly injected human cells
Marta Lai1, Cristina Cudalbu2, Marie-France Hamou3,4, Mario Lepore2, Lijing Xin2, Roy Thomas Daniel4, Andreas Felix Hottinger5, Monika Hegi3,4, and Rolf Gruetter1,6,7

1Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 2Animal Imaging and Technology Core (AIT), Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 3Laboratory of Brain Tumor Biology and Genetics, Neuroscience Research Center, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 4Service of Neurosurgery, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 5Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Lausanne, Switzerland, 6Department of Radiology, University of Geneva, Geneva, Switzerland, 7Department of Radiology, University of Lausanne, Lausanne, Switzerland

184 16:36
Multi-modal MRI Parametric Maps Combined with Receptor Information to Optimize Prediction of Pathologic Response to Neoadjuvant Chemotherapy in Breast Cancer
Hakmook Kang1,2, Allison Hainline1, Xia Li3, Lori R. Arlinghaus4, Vandana G. Abramson5,6, A. Bapsi Chakravarthy5,7, Brian Bingham8, and Thomas E. Yankeelov2,4,5,9

1Biostatistics, Vanderbilt University, Nashville, TN, United States, 2Center for Quantitative Science, Vanderbilt University, Nashville, TN, United States, 3GE Global Research, Niskayuna, NY, United States, 4Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 5Ingram Cancer Center, Vanderbilt University, Nashville, TN, United States, 6Medical Oncology, Vanderbilt University, Nashville, TN, United States, 7Radiation Oncology, Vanderbilt University, Nashville, TN, United States, 8School of Medicine, Vanderbilt University, Nashville, TN, United States, 9Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States

185
16:39
Early post-treatment changes of multi-parametric whole-body MRI quantitative parameters following Bortezomib induction in multiple myeloma; Preliminary results at 3.0 T
Arash Latifoltojar1, Margaret Hall-Craggs2, Alan Bainbridge2, Magdalena Sokolska2, Kwee Yong1, Neil Rabin2, Liam Watson1, Michelle Siu2, Matthew Benger2, Nikolaos Dikaios1, and Shonit Punwani1

1University College London, London, United Kingdom, 2University College London Hospital, London, United Kingdom

186
16:42
­The origins of glucoCEST signal: effect inhibiting glucose transport in brain tumors
Xiang Xu1,2, Jiadi Xu1,2, Linda Knutsson3, Yuguo Li1,2, Huanling Liu1,4, Guanshu Liu1,2, Bachchu Lal5,6, John Laterra5,6, Dmitri Artemov7,8, Michael T. McMahon1,2, Peter C.M. van Zijl1,2, and Kannie WY Chan1,2

1Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2FM Kirby Research Center, Kennedy Krieger Institute, Baltimore, MD, United States, 3Department of Medical Radiation Physics, Lund University, Lund, Sweden, 4Department of Ultrasound, Guangzhou Panyu Central Hospital, Panyu, China, People's Republic of, 5Department of Neurology, Kennedy Krieger Institute, Baltimore, MD, United States, 6Department of Neuroscience, Kennedy Krieger Institute, Baltimore, MD, United States, 7Division of Cancer Imaging Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 8JHU In Vivo Cellular Molecular Imaging Center, Baltimore, MD, United States

187 16:45
CEST Metrics for Assessing Early Response to Stereotactic Radiosurgery in Human Brain Metastases
Kimberly L. Desmond1,2, Hatef Mehrabian1,2, Arjun Sahgal1,3, Hany Soliman1,3, and Greg J. Stanisz1,2

1Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada, 2Medical Biophysics, University of Toronto, Toronto, ON, Canada, 3Radiation Oncology, Odette Cancer Centre, Toronto, ON, Canada

188 16:48
Predicting TP53 mutational status of breast cancers on clinical DCE MRI using directional-gradient based radiogenomic descriptors
Nathaniel Braman1, Prateek Prasanna1, Donna Plecha2, Hannah Gilmore2, Lyndsay Harris2, Kristy Miskimen1, Tao Wan3, Vinay Varadan1, and Anant Madabhushi1

1Case Western Reserve University, Cleveland, OH, United States, 2University Hospitals, Cleveland, OH, United States, 3Beihang University, Beijing, China, People's Republic of

189 16:51
A Prototype Image Quality Assurance System for Accelerated Quantitative Breast DCE-MRI
Yuan Le1, Aneela Afzal2, Xiao Chen3, Bruce Spottiswoode4, Wei Huang2, and Chen Lin1

1Radiology and Imaging Science, Indiana University School of Medicine, Indianapolis, IN, United States, 2Advanced Imaging Research Center, Oregon Health and Science University, Portland, OR, United States, 3Siemens Healthcare, Princeton, NJ, United States, 4Siemens Healthcare, Chicago, IL, United States

190 16:54
Model Evolution Concept in Dynamic Contrast Enhanced MRI for Prediction of Tumor Interstitial Fluid Pressure
Hassan Bagher-Ebadian1,2, Azimeh NV Dehkordi3, Rasha Alamgharibi2, Tavarekere Nagaraja1, David Nathanson1, Hamid Soltanian-Zadeh1, Stephen Brown1, Hamed Moradi4, Ali Arbab5, and James R Ewing1,2

1Henry Ford Hospital, Detroit, MI, United States, 2Oakland University, Rochester, MI, United States, 3Shahid Beheshti University, Tehran, Iran, 4Tarbiat Modares University, Tehran, Iran, 5Georgia Regents University, Augusta, GA, United States

191 16:57
Automation of Pattern Recognition Analysis of Dynamic Contrast-Enhanced MRI Data to Assess the Tumor Microenvironment
SoHyun Han1, Radka Stoyanova2, Jason A. Koutcher3, HyungJoon Cho1, and Ellen Ackerstaff3

1Ulsan National Institute of Science and Technology, Ulsan, Korea, Republic of, 2Miller School of Medicine, University of Miami, Miami, FL, United States, 3Memorial Sloan Kettering Cancer Center, New York, NY, United States

192 17:00
In vivo measurement of tumor T1 relaxation time using a whole body clinically feasible multiple flip angle method can predict response to chemotherapy
Harbir Singh Sidhu1, Anna Barnes2, Nikolaos Dikaios1, Scott Rice1, Alan Bainbridge3, Robert Stein4, Sandra Strauss5, David Atkinson1, Stuart Taylor1, and Shonit Punwani1

1Centre for Medical Imaging, University College London, London, United Kingdom, 2Institute of Nuclear Medicine, University College London Hospital, London, United Kingdom, 3Medical Physics and Biomedical Engineering, University College London Hospital, London, United Kingdom, 4Medical Oncology, University College London Hospital, London, United Kingdom, 5Research Department of Oncology, University College London, London, United Kingdom

193
17:03
Quantitative Susceptibility Mapping to Interrogate Colorectal Metastases in Mouse Liver during Normoxia and Hyperoxia
Eoin Finnerty1, Rajiv Ramasawmy2, James O'Callaghan2, Mark F Lythgoe2, Karin Shmueli1, David L Thomas3, and Simon Walker-Samuel2

1Medical Physics and Biomedical Engineering, University College London, London, United Kingdom, 2University College London, London, United Kingdom, 3Institute of Neurology, University College London, London, United Kingdom

194
17:06
Early Brain Tumor Detection by Active-Feedback MRI
Zhao Li1, Chaohsiung Hsu1, Ryan Quiroz1, and Yung-Ya Lin1

1Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA, United States

195 17:09
In Vivo Conductivity Imaging of Rat Tumor Model Using MRI
Jiaen Liu1, Qi Shao1, Yicun Wang1, Gregor Adriany2, John Bischof3, Pierre-Francois Van de Moortele2, and Bin He1,4

1Biomedical Engineering, Univeristy of Minnesota, Minneapolis, MN, United States, 2Center for Magnetic Resonance Research, Univeristy of Minnesota, Minneapolis, MN, United States, 3Mechanical Engineering, Univeristy of Minnesota, Minneapolis, MN, United States, 4Institute for Engineering in Medicine, Univeristy of Minnesota, Minneapolis, MN, United States

196 17:12
Evaluation of T2W MRI-derived Textural Entropy for Assessment of Prostate Cancer Aggressiveness
Gabriel Nketiah1, Mattijs Elschot1, Eugene Kim 1, Tone Frost Bathen 1, and Kirsten Margrete Selnæs1

1Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway


Oral

MR-Guided Interventions

Room 300-302 16:30 - 18:30 Moderators:Joshua de Bever & Axel Krafft

197 16:30
Rapid Device Localization for Prospective Stereotaxy: Using Computation Instead of Imaging
Miles E. Olsen1, Ethan K. Brodsky1, Jonathan A. Oler2, Marissa K. Riedel2, Eva M. Fekete2, Ned H. Kalin2, and Walter F. Block1

1Medical Physics, University of Wisconsin - Madison, Madison, WI, United States, 2Psychiatry, University of Wisconsin - Madison, Madison, WI, United States

We present a technique for rapidly aiming interventional devices during prospective stereotaxy procedures. Our approach enables accurate computational determination of trajectory guide orientation and the true physical pivot point of frameless stereotaxy guides that mount on the skull.

 

Historically, these neurosurgical tasks require minutes per iterative cycle consisting of: scan, interpret image, adjust aim, repeat – or no intraoperative imaging at all, relying on preoperative images registered to stereotactic frame coordinates. Our rapid technique (~5 FPS) is closer to the clinician’s preferred responsiveness of optical tracking of devices in the OR (~30 FPS).


198 16:42
Evaluation of Infection Risk for MR Guided DBS Implantations in a Radiology Suite
Alastair Martin1, Paul Larson2, Nadja Levesque2, Jill Ostrem3, and Philip Starr2

1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, 2Neurological Surgery, UCSF, San Francisco, CA, United States, 3Neurology, UCSF, San Francisco, CA, United States

Hardware infection incidence for DBS implantations performed in a diagnostic MR suite is reported.  A total of 164 DBS procedures were performed in movement disorder patients resulting in six (3.7%) hardware related infections.  Two infections occurred within the first 10 cases and led to a change in sterile practice.  Over the last 154 cases four (2.6%) infections have been reported and all were associated with implantation of the IPG controller, which is done in a separate surgical procedure 1-3 weeks after DBS implantation.  Infection risk when implanting DBS electrodes in a diagnostic MR suite is comparable to conventional OR procedures.   

199 16:54
Time-resolved 23-Na Imaging for Monitoring of Thermochemical Ablation Injections
Nicolas G.R. Behl1, Armin M. Nagel1,2, Erik N.K. Cressman3, Reiner Umathum1, David Fuentes4, R. Jason Stafford4, Peter Bachert1, Mark E. Ladd1, and Florian Maier1

1Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Diagnostic and Interventional Radiology, University Medical Center Ulm, Ulm, Germany, 3Interventional Radiology, M. D. Anderson Cancer Center, Houston, TX, United States, 4Imaging Physics, M. D. Anderson Cancer Center, Houston, TX, United States

Thermochemical ablation (TCA) is a novel minimally invasive ablation approach. Acetic acid and sodium hydroxide are injected simultaneously and mix and react directly before entering the tissue. The exothermal reaction releases heat that is used for thermal ablation. For a detailed characterization of TCA injection, 4D 23Na-data with reasonable temporal resolution are required. In this work, a compressed sensing approach was applied to acquire 4D 23Na-data of injections with high spatial and good temporal resolution.

200
17:06
Intrinsic MR visualization of RF lesions using IR-SSFP after MR-guided ablation
Philippa Krahn1,2, Venkat Ramanan2, Labonny Biswas2, Nicolas Yak2, Kevan Anderson2, Jennifer Barry2, Sheldon Singh3, Mihaela Pop1,2, and Graham A Wright1,2

1Medical Biophysics, University of Toronto, Toronto, ON, Canada, 2Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada, 3Cardiology, Sunnybrook Health Sciences Centre, Toronto, ON, Canada

Here we explored an efficient imaging protocol for visualizing both the edema (reversible) and necrosis (irreversible) regions of myocardial injury in RF lesions. Using an MR-guided catheter system, we performed ablation in swine, immediately followed by T1-based imaging (IR-SSFP) and T2 mapping (T2-prepared SSFP) for lesion characterization. The areas of edema segmented from IR-SSFP images and T2 maps were visually similar and showed good correlation. IR-SSFP is known to visualize lesion cores at a specific TI--selecting an additional TI which emphasizes edema, we successfully demonstrated that both regions could be visualized by a single IR-SSFP acquisition.

201
17:18
In-vivo echo-navigated MR thermometry for real-time monitoring of cardiac radiofrequency ablation
Solenn Toupin1,2, Matthieu Lepetit-Coiffe2, Pierre Bour1, Valery Ozenne1, Baudouin Denis de Senneville3, Rainer Schneider4, Kimble Jenkins5, Arnaud Chaumeil1, Pierre Jais1, and Bruno Quesson1

1IHU-LIRYC, Bordeaux, France, 2Siemens Healthcare, Saint Denis, France, 3Mathematical Institute of Bordeaux, Bordeaux, France, 4Siemens Healthcare, Erlangen, Germany, 5MRI Interventions, Irvine, CA, United States

The visualization of lesion formation in real time is one potential benefit of carrying out radiofrequency ablation (RFA) under magnetic resonance (MR) guidance in the treatment of ventricular arrhythmia. In this study, we propose a real-time MR thermometry method to visualize online the temperature distribution in the myocardium during catheter-based RFA. An echo-navigated sequence is used with slice tracking to compensate respiratory-induced through-plane motion and allow all image orientation. The method was evaluated during free breathing in 5 healthy volunteers and during RF delivery on the left ventricle (LV) of a sheep in vivo.

202 17:30
GPU Accelerated Dynamic Respiratory Motion Model Correction for MRI-Guided Cardiac Interventions
Robert Xu1,2 and Graham Wright1,2

1Medical Biophysics, University of Toronto, Toronto, ON, Canada, 2Schulich Heart Research Program, Sunnybrook Research Institute, Toronto, ON, Canada

The objective of this study is to explore the use of a rapidly updated dynamic motion model to correct for respiratory motion induced errors during MRI-guided cardiac interventions. The motivation for the proposed technique is to improve the accuracy of MRI guidance by taking advantage of the anatomical context provided by the high-resolution prior images and the respiratory motion information present in a series of real-time MR images. To achieve this goal, the proposed dynamic motion model is updated continuously, and is used to predict the motion estimate for realigning the prior volume with the real-time images during an intervention.

203 17:42
An MR-compatible Assistance System for MR-guided Needle Interventions: Initial Phantom Evaluation
Axel Joachim Krafft1,2,3, Simon Reiss2, Andreas Reichert2, Michael Vogele4, and Michael Bock2

1German Cancer Consortium (DKTK), Heidelberg, Germany, 2Radiology – Medical Physics, University Medical Center Freiburg, Freiburg, Germany, 3German Cancer Research Center (DKFZ), Heidelberg, Germany, 4iSYS Medizintechnik GmbH, Kitzbuehel, Austria

Minimally invasive interventions highly benefit from imaging guidance during instrument positioning and monitoring of therapeutic progress. MRI with its unique soft tissue contrast and ability for functional imaging is ideally suited for interventional guidance. To enable and facilitate minimally invasive interventions in closed-bore high-field MR systems with small bore diameters that severely limit patient access, we propose a novel, versatile assistance system in combination with passive instrument tracking. The system was studied in a systematic phantom experiment during needle procedures, and a mean targeting accuracy of less than 2 mm was achieved (mean procedure time: 6.5 min). 

204
17:54
Dual echo z-shimmed sequence for PRF-shift MR thermometry near metallic ablation probes
Yuxin Zhang1 and William A Grissom2

1Biomedical Engineering, Tsinghua University, Beijing, China, People's Republic of, 2Biomedical Engineering, Vanderbilt University Institute of Imaging Science, Nashville, TN, United States

Signal loss induced by ablation probe prevents accurate temperature monitoring where the thermal dose is highest. To address this problem, a dual echo sequence with z-shimming is proposed to recover the signal and an associated penalized likelihood approach is applied to estimate a single temperature map from both echoes. Phantom experiments were conducted to validate the effect of the proposed sequence. Evident signal recovery is shown in the magnitude images and temperature maps with heating. Standard deviation maps with no heating are presented to reflect the large reduction in uncertainty over time with dual-echo z-shimmed thermometry.

205
18:06
In vivo monitoring of percutaneous thermal ablation by simultaneous MR Elastography and Thermometry
Nadège Corbin1, Jonathan Vappou1, Pramod Rao1, Benoit Wach1, Laurent Barbé1, Pierre Renaud1, Michel de Mathelin1, and Elodie Breton1

1ICube-University of Strasbourg, Strasbourg, France

MR-guided percutaneous thermal ablations are currently monitored by MR thermometry. However, no information related to intrinsic property changes of the tissue is available during the procedure. The feasibility of monitoring in vivo thermal ablations by simultaneous Magnetic Resonance Elastography (MRE) and MR-thermometry is demonstrated in this work. The interventional MRE system includes a needle MRE driver, a respiratory triggered gradient-echo sequence with motion encoding and an online reconstruction method that provides elasticity and temperature measurements in real-time.  Changes in elasticity and temperature occurring during laser thermal ablation are successfully measured in vivo over 20 minutes thanks to this interventional MRE system.

206 18:18
Preliminary evaluation of R2*-based temperature mapping for predicting the kill zone in MRI-guided renal cryoablation
Junichi Tokuda1, Kemal Tuncali1, Lisanne Kok1,2, Vincent M Levesque 1, Ravi T Seethamraju 3, Clare M Tempany1, and Ehud J Schmidt1

1Department of Radiology, Brigham and Women's Hospital, Boston, MA, United States, 2Eindhoven University of Technology, Eindhoven, Netherlands, 3Siemens Healthcare, Boston, MA, United States

We tested the feasibility of R2*-based temperature mapping using a PETRA UTE sequence to determine the “kill zone” within an ice ball in the kidney during MRI-guided renal cryoablation. R2*-maps were calculated from dual-echo PETRA images acquired during six renal cryoablation cases, and converted to temperature maps using R2*-temperature calibrations performed in swine kidneys. We compared ablation volumes estimated from (a) the -20°C boundary on the temperature maps; (b) the signal void on intra-procedural T2-weighted images; and (c) post-ablation contrast-enhanced MRI as the “gold standard”. Results show that R2*-based temperature maps provided a reliable lower limit of the kill-zone volume.


Oral

Diffusion Acquisition

Room 324-326 16:30 - 18:30 Moderators:Kawin Setsompop

207 16:30
Optimal data acquisition for application to the continuous time random walk diffusion model
Thomas Richard Barrick1, Andrew Mott1, Diggory North1, and Franklyn Arron Howe1

1Neuroscience Research Centre, St George's, University of London, London, United Kingdom

This study aims to optimise diffusion-weighted MRI (DW-MRI) acquisition for applications involving the continuous time random walk (CTRW) diffusion model. Minimum acquisition time and effects of inversion recovery are considered.  Optimisation indicates a 6 minute 4 b-value DW-MRI acquisition is sufficient for diffusion tensor data. Inversion recovery significantly reduces the variability in calculated α, β and ADC due to effects of CSF in grey matter and periventricular white matter. Analysis of water diffusion in brain with the CTRW model may reveal more subtle effects of neuronal damage than conventional DWI.

208 16:42
The Effects of Navigator Distortion Level on Interleaved EPI DWI Reconstruction: A Comparison between Image and K-space Based Method
Erpeng Dai1, Xiaodong Ma1, Zhe Zhang1, Chun Yuan1,2, and Hua Guo1

1Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, People's Republic of, 2Vascular Imaging Laboratory, Department of Radiology, University of Washington, Seattle, WA, United States

One of the challenges for interleaved EPI (iEPI) DWI is the phase inconsistency among different shots. Several methods, performed either in the image or k-space domain, have been proposed to solve this problem with extra acquired navigator data. However, the navigator is usually acquired with a lower bandwidth in the phase encoding direction than the image echo, which can cause different distortion levels. In this study, the effects of such distortion for the image or k-space based reconstruction are investigated. It has been shown that the k-space based method is more tolerant to the navigator distortion.

209 16:54
Experimental detection of imaginary signals in diffusion pore imaging using double diffusion encoding
Kerstin Demberg1, Frederik Bernd Laun1, Johannes Windschuh1, Reiner Umathum1, Peter Bachert1, and Tristan Anselm Kuder1

1Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany

By diffusion pore imaging, the average shape of arbitrary closed pores in an imaging volume element can be detected employing a long-narrow gradient profile. Alternative approaches use short gradient pulses only. Until now, however, diffusion pore imaging of non-point-symmetrically shaped pores has not been demonstrated using short gradient pulses only. In this abstract, we present a first experimental verification using double diffusion encoded experiments. Non-point-symmetric pores result in non-vanishing imaginary parts in the double diffusion encoded signal. Thus the phase of the form factor can be estimated with an iterative approach. This allows for unambiguous pore image reconstruction.

210 17:06
Virtual Coil Reconstruction for 3D Diffusion-Weighted Multi-Shot MRI using a Single Reference Shot.
Eric Y. Pierre1, Jacques-Donald Tournier1,2, and Alan Connelly1

1Florey Institute of Neuroscience and Mental Health, Melbourne, Australia, 2Centre for the Developing Brain, King's College London, London, United Kingdom

We introduce an efficient Mult-Shot Diffusion-Weighted (DW) 3D-GRASE acquisition and reconstruction technique to produce DW image volumes free of motion-induced phase artifacts, without relying on explicit measurement or inference of the phase information. The method replaces navigators measurements by a single reference scan for the whole acquisition. Virtual Coil concepts for Parallel Imaging techniques are used to map the multi-shot data onto a k-space signal with consistent phase information.

211
17:18
Convex Optimized Diffusion Encoding (CODE) Gradient Waveforms for Minimum TE and Bulk Motion Compensated Diffusion Weighted MRI
Eric Aliotta1,2, Holden H Wu1,2, and Daniel B Ennis1,2

1Radiological Sciences, UCLA, Los Angeles, CA, United States, 2Biomedical Physics IDP, UCLA, Los Angeles, CA, United States

Spin-Echo EPI Diffusion Weighted MRI (SE-EPI DWI) typically uses a  diffusion encoding gradient waveform with two identical gradients on either side of the 180° pulse which, in combination with the temporal footprint of the EPI readout results in sequence dead time. This dead time can be used for additional diffusion encoding which can, in turn, reduce TE and/or be used to null gradient moments for bulk motion compensated diffusion encoding. Convex Optimized Diffusion Encoding (CODE) was developed to minimize TE for DWI with and without motion compensation, implemented on a clinical scanner and tested in volunteers.

212 17:30
Detection of Microscopic Diffusion Anisotropy in Human Brain Cortical Gray Matter in Vivo with Double Diffusion Encoding
Marco Lawrenz1 and Juergen Finsterbusch1

1Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

Double diffusion encoding experiments with two weighting periods applied successively in the same acquisition offer access to microscopic tissue properties. Rotationally invariant measures of the so-called microscopic diffusion anisotropy as a marker for cell or compartment shape have reliably been determined in brain white matter. In this study, it is demonstrated that microscopic diffusion anisotropy can also be detected in cortical gray matter in vivo and measures of it can be determined extending first evidences presented recently. However, an inversion recovery pulse is required to null white matter signals and avoid partial volume effects.

213 17:42
High-resolution diffusion imaging at 7T using 3D multi-slab EPI
Wenchuan Wu1, Peter J Koopmans1, Robert Frost1, Myung-Ho In2, Oliver Speck3, and Karla L Miller1

1FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 2Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States, 3Department of Biomedical Magnetic Resonance, Otto-von-Guericke University, Magdeburg, Germany

In this work, we combined 3D multi-slab imaging (optimal SNR efficiency for spin-echo sequence) and 7T (higher SNR) to enhance diffusion imaging. With the newly developed Slice-FLEET technique and NPEN correction, we successfully achieved robust high resolution diffusion MRI at 7T with high SNR.

214 17:54
Efficient quiet multiband accelerated HARDI fetal Diffusion
Jana Maria Hutter1, J-Donald Tournier1, Anthony N Price1, Lucilio Cordero Grande1, Emer Judith Hughes1, Kelly Pegoretti1, Laura McCabe1, Mary Rutherford1, and Joseph V Hajnal1

1Centre for the developing brain, King's College London, London, United Kingdom

 Fetal diffusion MRI analysis is often limited by the ability of the conventional ssEPI to allow an efficient, high-resolution acquisition, able to produce multi-shell high angular resolution dMRI data as required by advanced analysis tools. This abstract presents a novel, multiband accelerated, sinusoidal, quiet and efficient ssEPI acquisition. The first results on 3 fetuses with 54 directions show promising data quality and significantly decreased scan time.

215 18:06
Microscopic Anisotropy of the Rat Spinal Cord In vivo with DW PRESS
Matthew Budde1 and Nathan Skinner1

1Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, United States

Diffusion weighted imaging of the spinal cord has seen promising applications to diagnosis and prognosis, yet it is limited by technical challenges.  This work presents the implementation of diffusion weighted spectroscopy of the water signal in the rat spinal cord in vivo with the goal of reducing acquisition times and post processing requirements to promote wider clinical feasibility.

216 18:18
Diffusion-weighted MRI using undersampled radial STEAM with iterative image reconstruction
Andreas Merrem1, Jakob Klosowski1, Sabine Hofer1, Klaus-Dietmar Merboldt1, and Jens Frahm1

1Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für Biophysikalische Chemie, Göttingen, Germany

Single-shot STEAM MRI is a method for black-blood diffusion-weighted imaging where the use of radiofrequency-refocussed echoes leads to no image distortions, no susceptibility artifacts, and no violations of the Carr-Purcell-Meiboom-Gill condition. Despite these favorable properties, clinical applications have been limited by a low signal-to-noise ratio. Here, we demonstrate the development of highly undersampled radial diffusion-weighted single-shot STEAM MRI with iterative reconstruction to achieve acceptable signal-to-noise for studies of the human brain.


Oral

fMRI in Disease

Room 331-332 16:30 - 18:30 Moderators:Qiyong Gong & Jie Tian

217 16:30
Presurgical brain mapping in epilepsy using simultaneous EEG and functional MRI at ultra-high field: feasibility and first results
Frédéric Grouiller1, Joao Jorge2,3, Francesca Pittau4, Wietske van der Zwaag 5,6, Christoph M Michel7, Serge Vulliémoz 4, Rolf Gruetter2, Maria I Vargas8, and François Lazeyras1

1Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland, 2Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 3Institute for Systems and Robotics, Department of Bioengineering, Instituto Superior Técnico, University of Lisbon, Lisbon, Portugal, 4EEG and Epilepsy Unit, Department of Neurology, Geneva University Hospital, Geneva, Switzerland, 5Biomedical Imaging Research Center (CIBM), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 6Spinoza Centre for Neuroimaging, Amsterdam, Netherlands, 7Functional Brain Mapping Laboratory, Department of Fundamental Neurosciences, University of Geneva, Geneva, Switzerland, 8Division of Neuroradiology, Geneva University Hospital, Geneva, Switzerland

The aim of this study was to demonstrate that EEG can be used safely at ultra-high field to locate epileptic focus and functional eloquent cortex in patients. We recorded simultaneous EEG-fMRI at 7T in 9 patients. Despite large artifacts in intra-MRI EEG recordings, it was possible to detect interictal epileptiform discharges and to perform noise-sensitive topography-related analyses. Using an optimized setup and appropriate artifact removal algorithms, localization of epileptic networks and of functional eloquent cortex is possible at ultra-high field. Therefore, the increased fMRI sensitivity offered by this technology may be beneficial to improve presurgical evaluations of patients with epilepsy.

218 16:42
High-Frequency and Other Pathological Network Hemodynamics Observed in Epilepsy Patients Imaged With Multi-Band Multi-Echo BOLD Functional MRI at 7T
Prantik Kundu1,2, Lara V. Marcuse3, Bradley Delman1, Rebecca Feldman1, Madeline C. Fields3, and Priti Balchandani1

1Department of Radiology, Icahn School of Medicine at Mt. Sinai, New York, NY, United States, 2Department of Psychiatry, Icahn School of Medicine at Mt. Sinai, New York, NY, United States, 3Department of Neurology, Icahn School of Medicine at Mt. Sinai, New York, NY, United States

Clinical assessment of epilepsy based on extra-cranial EEG electrophysiology has moderate diagnostic sensitivity (40%), poor spatial specificity (1-5 cm), and no prognostic value. We seek to utilize MRI for more effective non-invasive characterization of epilepsy than currently established. We implemented multi-echo multi-band (MEMB) BOLD fMRI at 7T to map the hemodynamic signatures of seizure zones and networks in spontaneous brain activity of focal epilepsy patients versus matched controls. We mapped seizure networks in patients at millimeter-resolution, and observed epileptiform BOLD to have significantly amplified infra-slow and high-frequency temporal oscillations, analogous to characteristic epileptiform activity from EEG. 

219 16:54
Mapping resting state networks in epilepsy with Arterial Spin Labeling connectivity analysis
Ilaria Boscolo Galazzo1,2, Silvia Francesca Storti3, Anna Barnes1, Enrico De Vita4, Francesca Benedetta Pizzini2, John Duncan5, Ashley Groves1, Gloria Menegaz3, and Francesco Fraioli1

1Institute of Nuclear Medicine, University College London, London, United Kingdom, 2Department of Neuroradiology, University Hospital Verona, Verona, Italy, 3Department of Computer Science, University of Verona, Verona, Italy, 4Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, United Kingdom, 5Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, United Kingdom

In this study, we propose the assessment of resting-state brain networks (RSNs) using Arterial Spin Labeling perfusion MRI as an alternative to the gold-standard sequence represented by the Blood-oxygenation-level-dependent (BOLD) contrast. RSNs have been derived by means of independent component analysis (ICA) and spatially compared to literature networks. In addition, functional connectivity changes in epileptic patients have been quantified in comparison to healthy controls. The results demonstrated ASL suitability in identifying RSNs, with a strong agreement with BOLD, and in detecting functional alterations in pathological conditions.

220 17:06
BOLD Hemodynamic alteration in Brain Tumors
Lalit Gupta1, Rakesh K Gupta2, Prativa Sahoo1, Pradeep K Gupta2, Rana Patir3, Sandeep Vaishya3, Indrajit Saha4, and Walter Backes5

1Philips India Ltd., Bangalore, India, 2Department of Radiology, Fortis Memorial Research Institute, Gurgaon, India, 3Department of Neurosurgery, Fortis Memorial Research Institute, Gurgaon, India, 4Philips India Ltd., Gurgaon, India, 5Department of Radiology, Maastricht University Medical Center, Maastricht, Netherlands

The objective of the study is to determine the temporal delay in cerebral hemodynamic flow in brain tumors relative to normal brain tissue using rsfMRI and compare this with DCE derived cerebral blood volume(CBV) maps. Time series from all the voxels were cross-correlated with the mean time series from the normal hemisphere. The time point with maximum correlation was used to generate temporal shift map(TSM) for each voxel. We observed early hemodynamic changes in high grade glioma and found significant difference in the mean TSM ratio between Glioblastoma(GBM) and low grade tumors. TSM also appeared similar to rCBV perfusion maps. 

221 17:18
Investigating the impact of temporal signal fluctuations and local effective echo times on indices of BOLD sensitivity in healthy subjects and tumor patients at 7T.
Barbara Dymerska1, Pedro Cardoso1, Nina Mahr2, Eva Matt2, Florian Fischmeister2, Roland Beisteiner2, Siegfried Trattnig1, and Simon Daniel Robinson1

1High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 2High Field MR Centre, Department of Neurology, Medical University of Vienna, Vienna, Austria

Temporal signal fluctuations (tSNR) and local effective echo time (TElocal) are explored and their influence on BOLD sensitivity is investigated at 7T for healthy subjects and tumor patients, where prominent spatial variations in those two measures are expected. We show that tSNR may indicate sufficient sensitivity to detect activation but that BOLD sensitivity may be dramatically reduced by changes in TElocal close to pathologies and vital brain functions (motor, speech, auditory). Neglecting local TE variations can thus lead to false negative results in clinical fMRI. We thus suggest a new BOLD sensitivity metric based on TElocal∙tSNR.

222 17:30
Hemodynamic Alterations in Posttraumatic Stress Disorder and Mild Traumatic Brain Injury
Gopikrishna Deshpande1,2,3, D Rangaprakash1, Wenjing Yan1, Jeffrey S Katz1,2,3, Thomas S Denney1,2,3, and Michael N Dretsch4,5

1AU MRI Research Center, Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, United States, 2Department of Psychology, Auburn University, Auburn, AL, United States, 3Alabama Advanced Imaging Consortium, Auburn University and University of Alabama Birmingham, Birmingham, AL, United States, 4U.S. Army Aeromedical Research Laboratory, Fort Rucker, AL, United States, 5Human Dimension Division, HQ TRADOC, Fort Eustis, VA, United States

Functional MRI is an indirect measure of neural activity, as it is the convolution of the hemodynamic-response function (HRF) and a latent neural response. Recent studies show variance in HRF across brain regions and subjects. This raises the question of reliability of fMRI results if, for example, a canonical HRF is used in analysis. Using whole-brain resting-state fMRI, we employed blind hemodynamic deconvolution to estimate HRF parameters. We uncovered hemodynamic alterations in Soldiers with PTSD and mTBI, and found that certain subcortical and default-mode network regions showed significant alterations in HRF.

223 17:42
Assessment of brain cognitive functions in patients with vitamin B12 deficiency using resting state functional MRI
Lalit Gupta1, Rakesh K Gupta2, Pradeep K Gupta2, Hardeep Singh Malhotra3, Indrajit Saha4, and Ravindra K Garg3

1Philips India Ltd., Bangalore, India, 2Department of Radiology, Fortis Memorial Research Institute, Gurgaon, India, 3Department of Neurology, King George Medical University, Lucknow, India, 4Philips India Ltd., Gurgaon, India

The alterations in the brain cognitive functions due to vitamin B12 deficiency and reversibility of these alterations following therapy was studied using resting state fMRI. Regional Homogeneity (ReHo) was used to assess functional changes in patients with vitamin B12 deficiency. ReHo was significantly lower in patients than controls in the entire cerebrum and in the brain networks associated with cognition control i.e. default mode, cingulo-opercular and fronto-parietal network. We conclude that the brain networks associated with cognition control, in particular pre-frontal regions, are altered in patients with vitamin B12 deficiency that partially recovered following six weeks of replacement therapy.

224 17:54
Longitudinal Changes in Intrinsic Brain Activity in Cirrhotic Patients Before and One Month After Liver Transplantation
yue cheng1, Li-xiang Huang1, Shuang-shuang Xie1, Tian-yi Qian2, and Wen Shen1

1Tianjin First Central Hospital, Tianjin, China, People's Republic of, 2Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, People's Republic of

In this study, we evaluated brain activity changes in cirrhotic patients referred for liver transplantation (LT). Twenty cirrhotic patients and 25 healthy controls were included. Amplitude of low-frequency fluctuation (ALFF) values were compared between cirrhotic patients (pre- and post-LT) and healthy controls as well as patients pre- and post-LT. In cirrhotic patients, decreased ALFF in most brain regions can be reversed one month after LT, and the increased ALFF in temporal and frontal lobe may also return to normal. The reduced ALFF in the right supplementary motor area, inferior parietal lobule and calcarine persisted. One month after LT, the spontaneous brain activity partially renormalized, but complete cognitive function restoration may need a longer time.

225
18:06
Perils in the Use of Cross-validation for Performance Estimation in Neuroimaging-based Diagnostic Classification
Pradyumna Lanka1, D Rangaprakash1, and Gopikrishna Deshpande1,2,3

1AU MRI Research Center, Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, United States, 2Department of Psychology, Auburn University, Auburn, AL, United States, 3Alabama Advanced Imaging Consortium, Auburn University and University of Alabama, Birmingham, AL, United States

In this study, we highlight the fact that cross-validation accuracy might not be a good measure of performance estimation in neuroimaging-based diagnostic classification, especially with smaller sample sizes typically encountered in neuroimaging. We trained an array of classifiers using resting state fMRI-based functional connectivity measures from subjects in a particular age group using cross-validation, and then tested on an independent set of subjects with the same diagnosis (mild cognitive impairment and Alzheimer’s disease), but from a different age group. We demonstrate that cross-validation accuracy might give us an inflated estimate of the true performance of the classifiers.

226 18:18
fMRI indicates central TRPV1 modulation on gouty pain
Chiao-Chi Chen1, Yi-Hua Hsu1, Yi-Jen Peng2, Guo-Shu Huang3, and Chen Chang1

1Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, 2Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, 3Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan

Gout is one of the most painful forms of diseased conditions. Non-steroid anti-inflammatory drugs and colchicine are first-line agents for the acute attack, but these drugs are poorly tolerated or contraindicated in some patients. Elucidating the pain signaling pathway of gout may shed light on the key molecules that may be pursued as therapy targets in the future. Our neuroimaging, cellular, and molecular investigations regarding transient receptor potential vanilloid 1 (TRPV1) reveal a novel transduction pathway from the periphery to the brain during the attack of gout.


Oral

Human Brain Tumours: Diagnosis & Response to Therapy

Room 334-336 16:30 - 18:30 Moderators:Ravikanth Balaji & Natalie Serkova

227 16:30
Multi-Center and Multi-Vendor Study of Long-TE 1H MRS at 3T for Detection of 2-Hydroxyglutarate in Brain Tumors In Vivo
Changho Choi1, Thomas Huber2, Anna Tietze3, Byung Se Choi4, Jung Hee Lee5, Seung-Koo Lee6, Alexander Lin7, and Sunitha Thakur8

1UT Southwestern Medical Center, Dallas, TX, United States, 2Technical University of Munich, Munich, Germany, 3Aarhus University Hospital, Aarhus, Denmark, 4Seoul National University College of Medicine, Seongnam, Korea, Republic of, 5Sungkyunkwan University School of Medicine, Seoul, Korea, Republic of, 6Yonsei University College of Medicine, Seoul, Korea, Republic of, 7Harvard Medical School, Boston, MA, United States, 8Memorial Sloan-Kettering Cancer Center, New York, NY, United States

The non-invasive identification of elevated 2-hydroxyglutarate (2HG) in IDH-mutated gliomas by 1H MRS in vivo is a major breakthrough in brain tumor research. Studies have shown that optimized long-TE approaches may confer advantages over short-TE MRS for detecting 2HG. Here we report an evaluation of the feasibility of long-TE 2HG MRS in Philips, Siemens and GE 3T scanners. Echo times were optimized, with numerical simulations and phantom validation, for the vendor-specific RF pulses. In-vivo data from IDH-mutated glioma patients, obtained in the three vendors, are discussed.

228
16:42
Metabolic Profiling of Malignant Transformation and IDH-mutation in Diffuse Infiltrating Gliomas
Llewellyn Jalbert1, Adam Elkhaled1, Joanna J Phillips2, Evan Neill3, Marram P Olson3, Mitchel S Berger4, John Kurhanewicz1,3, Susan M Chang4, and Sarah J Nelson1,3

1Department of Bioengineering & Therapeutic Sciences, University of California, San Francisco (UCSF), San Francisco, CA, United States, 2Department of Pathology, University of California, San Francisco (UCSF), San Francisco, CA, United States, 3Department of Radiology & Biomedical Imaging, University of California, San Francisco (UCSF), San Francisco, CA, United States, 4Department of Neurological Surgery, University of California, San Francisco (UCSF), San Francisco, CA, United States

Patients diagnosed with infiltrating low-grade glioma have a relatively long survival, and a balance is often struck between treating the tumor and impacting quality of life. Aggressive treatments are typically reserved for lesions that have undergoing malignant transformation (MT) to a higher-grade lesion. Mutations in the isocitrate dehydrogenase 1 & 2 oncogenes and production of 2-hydroxyglutarate further characterize these tumors and are associated with improved outcome and treatment sensitivity. In this study, we found distinct metabolic profiles associated with patients' tumors that had undergone MT, as well as contained the IDH­-mutated genotype, using proton HR-MAS spectroscopy.

229
16:54
Noninvasive Assessment of IDH Mutational Status in Glioma using MR Elastography
Kay Pepin1, Arvin Arani1, Mona El Sheikh1, Nikoo Fattahi1, David Lake1, Armando Manduca1, Kiaran McGee1, Ian Parney1, Richard Ehman1, and John Huston1

1Mayo Clinic, Rochester, MN, United States

MR elastography (MRE) has been used to characterize the mechanical properties of normal and diseased brain tissue (1-4). This study evaluated MRE for the noninvasive characterization of gliomas, specifically investigating the relationship between tumor stiffness and mutations in the IDH1 gene, an important prognostic biomarker for improved outcome. Eighteen patients were enrolled in this study. MRE examinations were performed at 3T using an EPI-MRE sequence and 60Hz vibration frequency. Tumor stiffness was quantified and compared to IDH mutation status, as determined by histology. Twelve tumors were identified as IDH1 mutation positive and were significantly stiffer than tumors with non-mutated IDH1.  

230
17:06
Amide-Proton-Transfer-Weighted (APTw) MRI as a Surrogate Biomarker to Detect Recurrent High-grade Gliomas after Treatment with Chemoradiation: Validation by Image-Guided Stereotactic Biopsy
Shanshan Jiang1,2, Charles Eberhart3, Jaishri Blakeley4, Lindsay Blair4, Huamin Qin 3, Michael Lim5, Alfredo Quinones-Hinojosa5, Hye-Young Heo1, Yi Zhang1, Dong-Hoon Lee1, Xuna Zhao1, Zhibo Wen2, Peter C.M. van Zijl1, and Jinyuan Zhou1

1Department of Radiology, Johns Hopkins University, Baltimore, MD, United States, 2Department of Radiology, Southern Medical University Zhujiang Hospital, Guangzhou, China, People's Republic of, 3Department of Pathology, Johns Hopkins University, Baltimore, MD, United States, 4Department of Neurology, Johns Hopkins University, Baltimore, MD, United States, 5Department of Neurosurgery, Johns Hopkins University, Baltimore, MD, United States

We explored the imaging features of treatment effects and active tumor in glioma patients after surgery and chemoradiation using amide-proton-transfer-weighted (APTw) imaging at 3 Tesla. Needle biopsy samples were obtained for pathological validation. Corresponding APTw signal intensities were recorded. Results showed that APTw signal intensities had strong positive correlations with cellularity and proliferation. The active tumor had significantly higher APTw signal intensity, compared to treatment effects. The area-under-curve (AUC) for APTw intensities to differentiate treatment effects from active tumor was 0.959. APT imaging has potential for molecular image-guided biopsy for post-treatment glioma patients to distinguish pseudoprogression from tumor recurrence.

231 17:18
Amide Proton Transfer (APT) Imaging of Brain Tumors using 3D Fast Spin-Echo Dixon Method: Comparison with Separate B0 Mapping
Osamu Togao1, Akio Hiwatashi1, Jochen Keupp2, Koji Yamashita1, Kazufumi Kikuchi1, Masami Yoneyama3, and Hiroshi Honda1

1Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan, 2Philips Research, Hamburg, Germany, 3Philips Electronics Japan, Tokyo, Japan

Recently, the FSE Dixon APT acquisition protocol with intrinsic B0 correction was developed and implemented on 3T clinical MRI scanners. This technique allows simultaneous acquisition of APT imaging and intrinsic B0 mapping without increasing scan time. In the present study, we demonstrated the quantitative performance of the 3D FSE Dixon APT imaging of brain tumors in comparison with the separate B0 mapping method. 


232 17:30
Introducing steady state blood volume mapping using ferumoxytol, a new MRI tool to assess the intravascular space in brain tumors and other intracranial pathologies
Csanad Varallyay1, Daniel Schwartz2, Joao Prola Netto1, Prakash Ambady2, Andrea Horvath2, and Edward Neuwelt2

1Diagnostic Radiology and Neurology, Oregon Health and Science University, Portland, OR, United States, 2Neurology, Oregon Health and Science University, Portland, OR, United States

Steady state blood volume (SS-CBV) mapping using the blood pool agent ferumoxytol as an MRI contrast agent is feasible in brain tumors and other intracranial pathologies. It allows high resolution, distortion free blood volume maps, which can be a useful MRI tool to improve diagnosis and assessment of response to therapy. Ferumoxytol dose and MRI sequences may be optimized for various clinical applications. 

233 17:42
Semi-quantitative MRI Assessment of anti-PD1 Immunotherapy Response in Recurrent Glioblastoma
Lei Qin1,2, Xiang Li2,3, Amanda Stroiney4, David A Reardon1,2, and Geoffrey Young2,3

1Dana-Farber Cancer Institute, boston, MA, United States, 2Harvard Medical School, boston, MA, United States, 3Brigham and Women's Hospital, Boston, MA, United States, 4Northeastern University, Boston, MA, United States

The purpose of this study is to evaluate the predictive value of quantitative and semi-quantitative MRI biomarkers in determining patient benefit in anti-PD1 immunotherapy treatments. Longitudinal MRIs were performed on patients diagnosed with recurrent GBM. Volumetric analysis of abnormal tissue from contrast enhanced T1, FLAIR, and ADC revealed two distinct patterns: a) progressive increase volume in patients who derived no significant benefit, and b) a transient increase in the volume, followed by a delayed decrease in patients with >6 mo survival on trial. In this preliminary study (n=10), the data suggest that the volume of abnormal tissue on ADC seems to correlate better with patient benefit than abnormality on FLAIR and T1. 

234 17:54
Serial 3D H-1 MRSI of Patients with Newly Diagnosed GBM being Treated with Radiation, Temozolomide, Erlotinib and Bevacizumab
Sarah Nelson1, Yan Li1, Janine Lupo1, Marram Olson1, Jason Crane1, Annette Molinaro2, Ritu Roy3, Soonmee Cha1, and Susan Chang2

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, 3Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, United States

Patients with newly diagnosed GBM are typically treated with a combination of radiation and temozolomide in conjunction with a variety of investigational agents. Assessing the effectiveness of such therapies is complicated by differences in their mechanisms of action that lead to ambiguities in the interpretation of conventional anatomic images and difficulties in assessing the spatial extent of tumor.  The results of this study demonstrate that integrating 3D lactate edited H-1 MRSI into routine MR examinations and applying quantitative analysis methods allows for the objective evaluation of changes in tumor burden and the early assessment of outcome.  

235 18:06
Differential imaging biomarker response to sunitinib across tumor histologies in a prospective trial of brain metastases
Caroline Chung1, Brandon Driscoll1, Warren Foltz1, Cynthia Menard1, David Jaffray1, and Catherine Coolens1

1Princess Margaret Cancer Centre, Toronto, ON, Canada

Our preclinical study of sunitinib (SU) in combination with conformal large single fraction radiation in an orthotopic murine brain tumor model, discovered that changes in apparent diffusion coefficient (ADC), AUC and Ktrans were promising imaging biomarkers that could predict response to SU as well as combined SU and radiation. Based on our preclinical findings, we designed a prospective phase I trial of SU and radiosurgery (SRS) for brain metastases that incorporated translational investigation of these imaging biomarkers.  Here we summarize our discovery of differential ADC and AUC responses to sunitinib between renal cell cancer and other histology brain metastases.

236
18:18
Optimal time-window and perfusion protocol for MRI in early assessment of high grade glioma treatment response
Christopher Larsson1,2, Jonas Vardal1, Inge Rasmus Groote3, Magne Mørk Kleppestø1,2, Petter Brandal4, and Atle Bjørnerud1,5

1The Intervention Centre, Oslo University Hospital, Oslo, Norway, 2Faculty of Medicine, University of Oslo, Oslo, Norway, 3Department of Psychology, University of Oslo, Oslo, Norway, 4Department of Cancer Medicine, Surgery & Transplantation, Oslo University Hospital, Oslo, Norway, 5Faculty of Physics, University of Oslo, Oslo, Norway

Due to limitations in structural MRI in assessment of overall survival (OS) in high grade glioma interest in more advanced functional MRI methods has risen. A prospective longitudinal high grade glioma study including structural imaging and T1/T2* perfusion was performed in 27 patients to investigate the optimal time-window and most sensitive MRI perfusion method for early OS analysis.

No structural imaging, DSC or absolute perfusion parameter was found significant for early OS assessment. Change in median Ktrans and CBF from baseline to eight weeks was found significant and CBF change >15% most accurate predictor for poor OS.



Oral

Multiple Sclerosis: Novel Techniques & Studies

Hall 606 16:30 - 18:30 Moderators:Roland Henry & Jongho Lee

237
16:30
Association between cortical demyelination and structural connectomics in early multiple sclerosis
Gabriel Mangeat1,2, Russell Ouellette2,3, Constantina Andrada Treaba2,3, Tobias Granberg2,3, Elena Herranz2,3, Celine Louapre2,3, Nikola Stikov1,4, Jacob A. Sloane3,5, Eric C. Klawiter2,3,6, Caterina Mainero2,3, and Julien Cohen-Adad1,7

1Polytechnique Montreal, Montreal, QC, Canada, 2Athinoula A. Martinos Center for Biomedical Imaging, MGH, Charlestown, MA, United States, 3Harvard Medical School, Boston, MA, United States, 4Montreal Health Institute, Montreal, QC, Canada, 5Beth Israel Deaconess Medical Center, Boston, MA, United States, 6Department of Neurology, MGH, Boston, MA, United States, 7CRIUGM, Functional Neuroimaging Unit, Université de Montréal, Montreal, QC, United States

Multiple sclerosis (MS) is a chronic disorder of the central nervous system characterized by diffuse abnormalities along white matter tracts and demyelination, including cortical lesions. In this study, we explored the interplay between cortical and brain structural networks integrity in a cohort of early MS subjects by combining quantitative mapping of T2* and T1 relaxation rates from 7T MRI acquisitions to measure cortical demyelination with diffusion imaging and graph theory to assess the structural brain architecture. Results suggest that motor, premotor and anterior cingulate cortices are affected simultaneously by cortical demyelination and connectomics alterations, at a very early stage of MS.

238
16:42
Cerebellar-cerebral connections with the default mode network influence working memory performance in MS
Giovanni Savini1,2, Matteo Pardini3, Alessandro Lascialfari1,4, Declan Chard5, David Miller5, Egidio D'Angelo2,6, and Claudia Angela Michela Gandini Wheeler-Kingshott2,5

1Department of Physics, University of Milan, Milan, Italy, 2Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy, 3Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genoa, Genoa, Italy, 4Department of Physics, University of Pavia, Pavia, Italy, 5NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL, Institute of Neurology, University College London, London, United Kingdom, 6Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy

The cerebellum is linked to the default mode network (DMN) and its contribution to non-motor functions is now increasingly recognized. In Multiple Sclerosis (MS) motor and cognitive functions are both impaired. Here we aimed at assessing a possible link between cognition and cerebellar-cerebral fibers disruption in MS. Probabilistic tractography and graph theory derived metrics were compared to Symbol Digit Modalities Test (SDMT) scores in MS. We found that accounting for cerebellar-cerebral connections when calculating DMN graph metrics yielded a stronger correlation between network efficiency and SDMT scores, suggesting that disruption of the cerebellar-cerebral connections has significant cognitive consequences in MS.

239 16:54
Outer and inner cortical MTR abnormalities observed in clinically isolated syndromes
Rebecca Sara Samson1, Manuel Jorge Cardoso2,3, Wallace J Brownlee1, J William Brown1,4, Matteo Pardini5, Sebastian Ourselin2,3, Claudia Angela Michela Gandini Wheeler-Kingshott1,6, David H Miller1,7, and Declan T Chard1,7

1NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom, 2Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Bioengineering, University College London, London, United Kingdom, 3Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Institute of Neurology, London, United Kingdom, 4Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom, 5Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy, 6Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy, 7National Institute for Health Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre, London, United Kingdom

Cortical magnetization transfer ratio (cMTR) is potentially a sensitive measure of pathology linked with disease progression in relapse-onset multiple sclerosis (MS). We investigated outer cMTR changes in people following a clinically isolated syndrome (CIS), and compared those who later developed MS with those who did not. Compared with controls, the outer-to-inner cMTR ratio was significantly lower in patients who developed MS after 15 years but not in those who remained CIS. This suggests that the pathological processes underlying preferential reductions in outer cMTR start early in the clinical course of MS, and may be relevant to conversion to MS.

240 17:06
Variable Density Magnetization Transfer (vdMT) imaging for 7 T MR Imaging
Se-Hong Oh1, Wanyong Shin1, Jongho Lee2, and Mark J. Lowe1

1Imaging Institute, Cleveland Clinic Foundation, Cleveland, OH, United States, 2Laboratory for Imaging Science and Technology, Department of Electrical and Computer Engineering, Seoul National University, Seoul, Korea, Republic of

Because of the much higher SAR and longer acquisition time, in-vivo studies using MT at UHF have not been clinically feasible. In this work, we demonstrated a new approach (variable density MT [vdMT])for acquiring whole brain covered 7T MT data in a clinically reasonable time. vdMT provides similar image quality to that obtained with conventional MT imaging, and shortens the scan time by avoiding from SAR limitation. The proposed method generates high-resolution MT data in reasonable scan time and it exhibits high similarity with the conventional method. Moreover, it maintains sensitivity to MS lesions.

241 17:18
The neuroinflammatory component of gray matter pathology in multiple sclerosis by in vivo combined 11C-PBR28 MR-PET and 7T imaging
Elena Herranz1,2, Costanza Giannì1,2, Céline Louapre1,2, Constantina Andrada Treaba1,2, Sindhuja T Govindarajan1, Gabriel Mangeat1,3, Russell Ouellette1, Marco L Loggia1,2, Noreen Ward1, Eric C Klawiter1,2,4, Ciprian Catana1,2, Jacob A Sloane2,5, Jacob M Hooker1,2, Revere P. Kinkel6, and Caterina Mainero1,2

1Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada, 4Department of Neurology, Massachusetts General Hospital, Boston, MA, United States, 5Beth Israel Deaconess Medical Center, Boston, MA, United States, 6University of California, San Diego, CA, United States

In multiple sclerosis (MS) histopathological investigations implicated neuroinflammation through microglia and/or macrophages activation in the pathogenesis of cortical and subcortical diffuse damage. By combining 11C-PBR28 positron emission tomography (PET) imaging with anatomical 7T and 3T MRI, we investigated the presence and correlates of neuroinflammation in cortex and gray matter of subjects with MS. We found that neuroinflammation was present in thalamus, hippocampus, basal ganglia as well as cortex, particularly cortical lesions, and associated with structural damage, increased neurological disability and impaired information processing speed. Our data indicate that neuroinflammation is closely associated with neurodegeneration.

242 17:30
Quantitative Susceptibility Mapping (QSM) in patients with clinically isolated syndrome (CIS) and multiple sclerosis (MS) - a large cohort study
Ferdinand Schweser1,2, Jesper Hagemeier1, Paul Polak1, Michael G Dwyer1, Niels P Bergsland1,3, Nicola Bertolino1, Bianca Weinstock-Guttman4, Andreas Deistung5, Jürgen R Reichenbach5,6, and Robert Zivadinov1,2

1Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States, 2MRI Molecular and Translational Research Center, Jacobs School of Medicine and Biomedical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States, 3MR Research Laboratory, IRCCS Don Gnocchi Foundation ONLUS, Milan, Italy, 4Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States, 5Medical Physics Group, Department of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, 6Michael Stifel Center for Data-driven and Simulation Science Jena, Friedrich Schiller University Jena, Jena, Germany

Quantitative susceptibility mapping (QSM) is the most sensitive technique available for studying tissue iron in vivo. In this work, we applied QSM to more than 1000 patients with multiple sclerosis (MS) and almost 250 patients with clinically isolated syndrome (CIS). Our results provide strong support for changed deep gray matter iron concentrations in MS and CIS. 

243 17:42
Dissociated longitudinal patterns of neural activation, functional connectivity and structural connectivity in a mouse model of de- and re-myelination
Yi-Ching Lynn Ho1,2, Fiftarina Puspitasari1, Way-Cherng Chen1, and Kai-Hsiang Chuang1

1Singapore Bioimaging Consortium, Agency for Science, Technology & Research (A*STAR), Singapore, Singapore, 2Interdisciplinary Institute of Neuroscience & Technology (ZIINT), Zhejiang University, Hangzhou, China, People's Republic of

We hypothesized that structure and functional responses do not demonstrate the same pattern of impairment across time. Using the cuprizone mouse model of reversible demyelination, we show different longitudinal patterns of neural activation and functional connectivity, compared to healthy mice and also to the extent of cuprizone demyelination.

244
17:54
Hyperpolarized 13C MRSI can detect neuroinflammation in vivo in a Multiple Sclerosis murine model
Caroline Guglielmetti1,2, Chloe Najac1, Annemie Van der Linden2, Sabrina M Ronen1, and Myriam M Chaumeil1

1University of California San Francisco, San Francisco, CA, United States, 2University of Antwerp, Antwerp, Belgium

This study demonstrates that 13C MRS of hyperpolarized pyruvate can be used to detect increased lactate production from pro-inflammatory macrophages, mechanism mediated by pyruvate dehydrogenase kinase-1 upregulation and pyruvate dehydrogenase inhibition,  in a preclinical model of multiple sclerosis, hence providing a novel tool for in-vivo detection of neuroinflammation.

245
18:06
Axon Loss as an Outcome Measure for Assessing Therapeutic Efficacy
Tsen-Hsuan Lin1, Mitchell Hallman1,2, Mattew F. Cusick3, Jane E. Libbey3, Peng Sun1, Yong Wang1,4,5,6, Robert S. Fujinami3, and Sheng-Kwei Song1,5,6

1Radiology, Washington University School of Medicine, St. Louis, MO, United States, 2Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States, 3Pathology, University of Utah School of Medicine, Salt Lake City, UT, United States, 4Obstertic and Gynecology, Washington University School of Medicine, St. Louis, MO, United States, 5The Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States, 6Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, United States

Diffusion basis spectrum imaging (DBSI) has successfully distinguished co-existing pathologies in CNS, such as MS. The utility of DBSI derived “axon volume” has not been explored previously. In this study, we demonstrated the use of axon loss, reflecting irreversible tissue damage, as an outcome measure for assessing therapeutic efficacy in a mouse model of multiple sclerosis.  

246
18:18
In vivo 7T Quantitative Susceptibility Mapping of Cortical Lesions in Multiple Sclerosis
Wei Bian1, Eric Tranvinh1, Thomas Tourdias2, May Han3, Tian Liu4, Yi Wang4, Brian Rutt1, and Michael Zeineh1

1Department of Radiology, Stanford University, Stanford, CA, United States, 2Service de NeuroImagerie Diagnostique et Thérapeutique, CHU de Bordeaux, Bordeaux, France, 3Department of Neurology, Stanford University, Stanford, CA, United States, 4Department of Radiology, Weill Medical College of Cornell University, New York, NY, United States

Magnetic susceptibility measured with quantitative susceptibility mapping (QSM) has been proposed as a biomarker for inflammation in multiple sclerosis (MS) white matter (WM) lesions. However, a detailed in vivo characterization of cortical lesions has not been performed. In this study, the susceptibility in both cortical and WM lesions relative to adjacent normal-appearing parenchyma was measured and compared for 14 MS patients using QSM at 7T. Our results showed that relative susceptibility was negative for cortical lesions but positive for WM lesions. The opposite pattern of relative susceptibility suggests that iron loss dominates the susceptibility contrast in cortical lesions.


Oral

Automating & Speeding Algorithms

Summit 1 16:30 - 18:30 Moderators:James Pekar

247 16:30
Fully Automated Data Management and Quality Assurance in Very Large Prospective Cohort MR Imaging Studies – the MR Imaging Study within the German National Cohort
Jochen G. Hirsch1, Alexander Köhn1, Daniel C. Hoinkiss1, Jonas Peter1, Andreas Thomsen1, Matthias Günther1,2, and the German National Cohort MRI Study Investigators3

1Fraunhofer MEVIS, Bremen, Germany, 2University Bremen, Bremen, Germany, 3NAKO MR Imaging Core, Munich, Germany

We present a fully automated data management workflow and quality assurance, which is set up for large, multicentric cohort studies including whole-body MR imaging. The workflow includes a modality worklist, exam-synchronous DICOM transfer to centralized storage, quality control of MR acquisition, various image-based quality measures, web-based radiological image review for incidental findings, visual quality scores, as well as long-term archiving. This workflow, implemented in the MRI Study of the German National Cohort, enables to acquire and process more than 30 whole-body MRI scans per day, available for IF reading within 4 hours. Deviations, outliers, technical failures are pointed out on-the-fly.

248 16:42
Automated slice positioning for 2D MRA in bolus tracking of DCE-MRI
Takao Goto1 and Mirai Araki1

1MR Engineering, GE Healthcare, Hino-shi, Japan

Accurate placement of a 2D plane across the aorta while examining scout images is a complex task and  makes the operator's workflow difficult in bolus tracking of DCE-MRI. We present a new method for automated slice positioning for 2D MRA used to monitor bolus arrival. The 2D plane was planned by aorta detection using both Hough Forests and AdaBoost classifiers following the classification of axial images. A dataset with 40 patients was tested, and 35 cases depicted the cross section of the aorta clearly. This automation will help the operator and decrease the total study time.

249 16:54
Automatic Pipeline for Regional Brain Analyses in Demyelinated Mice
Emilie Poirion1, Daniel Garcia Lorenzo1, Isaac Adanyeguh1, Marie-Stéphane Aigrot1, Alexandra Petiet2, and Bruno Stankoff1,3

1Brain and Spine Institute, INSERM U1127/CNRS UMR 7225, Sorbonnes Universités, UPMC, CHU Pitié-Salpêtrière, 47 Bd de l'hôpital, 75013 Paris, Paris, France, 2Brain and Spine Institute, Center for Neuroimaging Research (CENIR), CHU Pitié-Salpêtrière, 47 Bd de l'hôpital, 75013 Paris, Paris, France, 3AP-HP, Saint Antoine Hospital, Department of Neurology, 184 Bd du Faubourg Saint Antoine, 75012 Paris, Paris, France

Experimental studies in mouse models offer the opportunity to combine in-vivo longitudinal high-field MRI and histological analyses. However, automatic MRI tools for processing rodent data to avoid manual processing are lacking. We proposed an automatic pipeline to perform systematic analyses on large murine cohorts with longitudinal data. We first applied artifacts correction as bias correction to optimize the subsequent steps. We then registered masks of regions of interest (ROIs) for our analyses onto each subject from which we extracted the quantitative data. This pipeline provides a way of quickly analyzing ROI regardless of disease models or the MRI sequence.

250 17:06
Improving robustness in automated slice positioning for knee MR by combining landmark detection and image processing
Takamasa Sugiura1, Shuhei Nitta1, Taichiro Shiodera1, Yuko Hara1, Yasunori Taguchi1, Tomoyuki Takeguchi1, Takuya Fujimaki2, Kensuke Shinoda2, Hiroshi Takai2, and Ayako Ninomiya2

1TOSHIBA CORPORATION, Kawasaki, Japan, 2TOSHIBA MEDICAL SYSTEMS CORPORATION, Otawara, Japan

We propose an improved automatic slice positioning algorithm for knee MR which combines conventional machine-learning based landmark detection with advanced image processing techniques. Conventional slice positioning methods determine the diagnostic slice center and orientation by detecting anatomical landmarks in the scout image. However, computing slice positions from landmarks can be inadequate since landmarks vary across patients and can be cut-off from scout images. Here, we use not only landmark detection but also image processing based contour detection of the femoral condyle and angle estimation of the femur and tibia to enable slice positioning for a wider range of scout images.

251
17:18
3D magnetic resonance fingerprinting with a clustered spatiotemporal dictionary
Pedro A. Gómez1,2, Guido Buonincontri3, Miguel Molina-Romero1,2, Cagdas Ulas1,2, Jonatahn I. Sperl2, Marion I. Menzel2, and Bjoern H. Menze1

1Technische Universität München, Garching, Germany, 2GE Global Research, Garching, Germany, 3Istituto Nazionale di Fisica Nucleare, Pisa, Italy

We present a method for creating a spatiotemporal dictionary for magnetic resonance fingerprinting (MRF). Our technique is based on the clustering of multi-parametric spatial kernels from training data and the posterior simulation of a temporal fingerprint for each voxel in every cluster. We show that the parametric maps estimated with a clustered dictionary agree with maps estimated with a full dictionary, and are also robust to undersampling and shorter sequences, leading to increased efficiency in parameter mapping with MRF. 

252 17:30
Multi-dimensional phase unwrapping: a new and efficient linear algebraic formulation using weighted least-squares
Laurent Lamalle1,2, Georgios Gousios3, and Matthieu Urvoy3

1Inserm US 17 & CNRS UMS 3552, Grenoble, France, 2Université Joseph Fourier & CHU de Grenoble, UMS IRMaGe, Grenoble, France, 3SFR RMN Biomédicale et Neurosciences, Université Joseph Fourier, Grenoble, France

Phase information of MR images can provide quantitative access to various physical properties of the examined sample, such as local $$$B_0$$$ values, magnetic susceptibility or flow. Phase is a continuous information whose estimation typically requires unwrapping. In this study, we propose a novel phase estimation algorithm which: (1) relies on a numeric scheme that is robust to phase jumps, and (2) is optimized for execution on modern parallel processors.

253 17:42
Fast liver FOV localization for improved liver-MRI workflow
Arathi Sreekumari1, K S Shriram1, Uday Patil1, Ersin Bayram2, Dattesh Shanbhag1, and Rakesh Mullick1

1GE Global Research, Bangalore, India, 2GE Healthcare, Houston, TX, United States

In this work we are focusing on automating the scan coverage and FOV for liver MRI acquisitions. We demonstrate that using fast scout images, we can achieve very good localization of liver FOV, irrespective of anatomy differences and hand-up / hands-down positioning.

254
17:54
Simultaneous measurement of short and long T2* components using hybrid encoding
Hyungseok Jang1,2, Curtis N Wiens1, and Alan B McMillan1

1Department of Radiology, University of Wisconsin, Madison, WI, United States, 2Department of Electrical and Computer Engineering, University of Wisconsin, Madison, WI, United States

In this study, we propose a highly time efficient quantitative imaging scheme where short and long T2* components can be simultaneously estimated. This method is based on a multi-echo UTE hybrid encoding scheme, where the central SPI region is oversampled to allow measurement of short T2* across a wide range of TEs. The UTE acquisition is immediately followed by a gradient echo train to measure long T2*. We show the proposed method can obtain an extensive number of images (e.g., approximately 750 images) within a single acquisition and reasonable scan time.

255 18:06
Automatic Classification of Brain Connectivity Matrices - a toolbox for supporting neuropsychiatric diagnosis
Ricardo Jorge Maximiano1, Tiago Constantino1,2,3, André Santos-Ribeiro1,4, and Hugo Alexandre Ferreira1

1Institute of Biophysics and Biomedical Engineering, Faculty of Sciences of the University of Lisbon, Lisbon, Portugal, 2Spitalzentrum Biel, Bienne, Switzerland, 3Lisbon School of Health Technology - ESTeSL, Lisbon, Portugal, 4Centre for Neuropsychopharmacology, Imperial College London, London, United Kingdom

In this work, a user-friendly toolbox that aims to classify automatically brain connectivity matrices is described. To test this tool, we used the Parkinson’s Progression Markers Initiative (PPMI) data which includes structural and functional Magnetic Resonance Imaging data of healthy subjects, patients with “scans without evidence for dopaminergic deficit” (SWEDD) and patients diagnosed with Parkinson’s Disease (PD). Using default parameters, this tool was able to achieve a maximum accuracy of 85.4% in classifying the 3 groups of subjects by selecting features that were related to the rostral middle frontal gyrus and splenium, which are in agreement with PD literature.

256
18:18
Rapid Two-Step QSM Without A Priori Information
Christian Kames1,2, Vanessa Wiggermann1,3,4, and Alexander Rauscher1,4

1UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada, 2Department of Engineering Physics, University of British Columbia, Vancouver, BC, Canada, 3Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 4Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada

Current state-of-the-art QSM reconstruction algorithms are plagued by the trade-off between reconstruction speed and quality. We propose a novel two-step dipole inversion algorithm 20x faster than MEDI and HEIDI, while producing qualitatively appealing images with a root-mean-square error less than MEDI’s and HEIDI’s when compared to COSMOS. The proposed method works by first reconstructing the well-conditioned k-space region through the use of a Krylov subspace solver, followed by a total variation minimization to fill in the ill-conditioned k-space region.


Oral

Quantitative MSK Imaging

Summit 2 16:30 - 18:30 Moderators:Delphine Perie & Yongxian Qian

257 16:30
Measurement and Compensation of Respiration-Induced B0 Variations for Bone Marrow Fat Quantification in Lumbar Spine
Yoonho Nam1, Joon-Yong Jung1, Hyun Seok Choi1, Eojin Hwang1, Hongpyo Lee2, and Dong-Hyun Kim2

1Department of Radiology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of, 2Department of Electrical and Electronic Engineering, Yonsei University, Seoul, Korea, Republic of

Fat fraction of the bone marrow has been suggested as an important quantitative parameter in the assessment of treatment response and determination of the benignity in oncologic imaging. Therefore, accurate fat quantification is a prerequisite for the fat fraction to be established as a reliable imaging biomarker. For this purpose, spoiled gradient echo sequences have been commonly used. However, gradient echo imaging is susceptible to B0 variations from various sources such as respiration, cardiac pulsation. In this study, we investigate and compensate the effects of respiration-induced B0 variations on fat quantification of the bone marrow in the lumbar spine.

258 16:42
Quantitative Muscle Perfusion with DCE-MRI Shows Distinct Load-Dependent Exercise-Stimulated Muscle Perfusion Patterns
Jeff L. Zhang1, Christopher Hanrahan1, Christopher C. Conlin1, Corey Hart2, Gwenael Layec2, Kristi Carlston1, Daniel Kim1, Michelle Mueller3, and Vivian S. Lee1

1Radiology, University of Utah, Salt Lake City, UT, United States, 2Internal Medicine, University of Utah, Salt Lake City, UT, United States, 3Vascular surgery, University of Utah, Salt Lake City, UT, United States

Noninvasive mapping of calf muscle perfusion with high spatial resolution has potential for assessing the severity of peripheral artery disease (PAD) and studying associated capillary density abnormality. We tested our novel DCE-MRI method to measure calf muscle hyperemia stimulated by plantar flexion at three different workloads. Increases in exercise load caused increased total perfusion in gastrocnemius, with a heterogeneous pattern at medium load and homogeneous at higher load. Perfusion in soleus did not increase until very heavy load of 16 lbs. DCE-MRI provides high spatial resolution measurement of post-exercise muscle perfusion.  

259 16:54
Gender Differences in Sodium Deposition in Muscle and Skin
Ping Wang1,2, Muge Serpil Deger3, Hakmook Kang4, T. Alp Ikizler3, Jens M. Titze5, and John C. Gore1,2

1Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States, 2Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, 3Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States, 4Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, United States, 5Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States

 
Sodium ions play a vital role in cellular homeostasis and electrochemical activity throughout the human body.  Previous studies have measured muscle and skin sodium contents in vivo in humans using MRI and have shown characteristic changes with age and as a result of pathological changes.  In this study, we found significant gender differences in sodium deposition between muscle and skin, with male has higher sodium content in skin than in muscle, while female has higher muscle sodium than skin sodium.  This observation seems to be more reliable with the increase of age.
 

260 17:06
Correlation of Mono-exponential and Bi-exponential UTE-T2* Analyses and Biomechanics in Human Achilles Tendons
Eric Y Chang1,2, Robert M Healey3, Reni Biswas2, Sheronda Statum2, Betty Tran2, Kenyu Iwasaki4, Jiang Du2, Won C Bae2, and Christine B Chung1,2

1Radiology Service, VA San Diego Healthcare System, San Diego, CA, United States, 2Department of Radiology, University of California, San Diego Medical Center, San Diego, CA, United States, 3Department of Orthopaedic Surgery, University of California, San Diego Medical Center, San Diego, CA, United States, 4Department of Orthopaedic Surgery, Kyushu University, Fukuoka, Japan

In this pilot study, we sought to determine if mono-exponential T2, mono-exponential UTE-T2*, or bi-exponential UTE-T2* correlated with biomechanical properties in human Achilles tendons. We found very high and significant correlation coefficients between mono-exponential T2* (rho = 0.90, p = 0.002) and bi-exponential T2* fractions (rho = -0.97, p < 0.001) obtained using the UTE-Cones sequence and ultimate tensile strain. Ultimate tensile strain represents the percentage change in tendon length prior to failure and high strains have been previously associated with tendon degeneration. Our results suggest that non-invasive MRI of the Achilles tendon may serve as a surrogate measure.

261 17:18
A comparison of denoising methods in dynamic MRS
Benjamin C Rowland1 and Alexander P Lin1

1Centre for Clinical Spectroscopy, Brigham and Women's Hospital, Boston, MA, United States

 MR spectroscopy is often used to study dynamic systems, such as muscle energetics using 31P. The need to perform temporal averaging to improve signal to noise ratios can compromise the temporal resolution of the measurements. Indirect time domain denoising can help to resolve this issue. In this study we evaluate six potential denoising approaches for dynamic MRS.

262 17:30
Extracting Quantitative Information From MRI Bound- and Pore-Water Maps of Cortical Bone
Mary Kate Manhard1, Sasidhar Uppuganti2, Mathilde C Granke2, Daniel F Gochberg3, Jeffry S Nyman2, and Mark D Does1

1Biomedical Engineering, Vanderbilt University, Nashville, TN, United States, 2Department of Orthopaedics & Rehabilitation, Vanderbilt University, Nashville, TN, United States, 3Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States

Bound and pore water concentration measures of cortical bone found from MRI have been shown to correlate with material properties of bone, but the ideal way to analyze and draw information from 3D quantitative maps remains unclear. Material properties of cadaver radii found from a 3-point bend test were correlated with characteristics of the distribution of bound and pore water concentrations (e.g. mean, skewness) in ROIs found from different segmentations. Results highlighted the importance of segmentation method as well as quantitative measures drawn from the maps.  

263 17:42
Detection of the meniscal blood supply changes in meniscal problems with Intravoxel incoherent motion MR imaging
Tan Guo1, Dandan Zheng2, Bing Wu2, and Min Chen1

1Radiology, Beijing Hospital, Beijing, China, People's Republic of, 2GE Healthcare, MR Research China, Beijing, Beijing, China, People's Republic of

The blood supply of meniscus is an essential indicator for the prognosis of meniscal problems. With a favorable blood supply of the teared meniscus, it’s tend to preserve the meniscus as much as possible at partial meniscetomy and meniscal repair. Intravoxel incoherent motion (IVIM) theory provide information about microcirculation of blood in addition to the pure molecular diffusion. The perfusion information detected with IVIM is emphasized on microvascular bed, which is the typical blood supply pattern of meniscus. In this study, IVIM model were used to estimate the change of vasculature in normal, degenerated and teared meniscus.

264 17:54
Orientation anisotropy of quantitative rotating and laboratory frame relaxation parameters in articular cartilage
Jari Rautiainen1, Lassi Rieppo2,3, Simo Saarakkala2,3,4, and Mikko Johannes Nissi1,5

1Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, 2Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland, 3Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland, 4Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland, 5Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland

Classical ($$$T_1$$$, $$$T_2$$$) and several rotating frame quantitative MR parameters have been used for evaluation of composition and structure of articular cartilage, and demonstrated to have variable sensitivity to tissue orientation. The orientation dependence of $$$T_1$$$, $$$T_2$$$, $$$T_2^*$$$, CW-$$$T_{1\rho}$$$ with four spin-lock amplitudes, adiabatic $$$T_{1\rho}$$$ with three different pulse modulations, adiabatic $$$T_{2\rho}$$$ and $$$T_{\rm RAFF}$$$ relaxation times were further investigated at 9.4T at different orientations of articular cartilage relative to B0 and compared with polarized light microscopy of the same tissue. $$$T_1$$$, adiabatic $$$T_{1\rho}$$$ with HS1-pulse and CW-$$$T_{1\rho}$$$ at 2 kHz spin-lock demonstrated the least orientation dependence.

265 18:06
The value of DWI with ADC mapping for assessing synovitis and bone erosion in early stage of RA
Xinwei Lei1, Jin QU1, Ying ZHAN1, Huixia Li1, and Yu Zhang2

1Tianjin First Center Hospital, Tianjin, China, People's Republic of, 2Philips Healthcare, Beijin, China, People's Republic of

The aim of study was to explore whether synovitis and bone erosion judged by ADC values correspond exactly or not to those judged by CE-MRI. 25 patients were examined by 3.0T MR including DWI and CE-MRI. ADC value of synovitis and bone erosion was significantly lower than that of joint effusion and cysts. ADC values of 2.0 was found distinguishing joint effusion from synovitis, and bone erosion from cysts. Therefore, MR diffusion provides additional information to the routine MRI sequences rendering it an effective non-invasive tool in differentiating between synovitis and joint effusion, as well as bone erosion and cysts.

266 18:18
Measurement of proteoglycan concentration in intervertebral discs assessed by 1HMRS at 1.5T
Lisa Maria Harris1,2, Ella Hodder2,3, Mara Cercignani2, Jan Bush2, Derek Convill3, Paul Colley1, and Nicholas Dowell2

1Radiological Sciences, Brighton and Sussex University Hospitals NHS Trust, Brighton, United Kingdom, 2Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom, 3Computing, Engineering and Mathematics, University of Brighton, Brighton, United Kingdom

An assessment was made to determine whether proteoglycan concentration could accurately be quantified at 1.5T using 1HMRS in a group of 13 healthy volunteers.  A peak from the N-acetyl resonance associated with proteoglycan was seen in all thirteen spectra, and reliably measured (308.8±59.9).  This compares favourably with studies performed at higher field strengths, thus showing that is it possible even at 1.5T to measure proteoglycans in intervertebral discs.


Combined Educational & Scientific Session

Quantitative Biomarkers in Renal MRI: Adding Physiologic Information to the Morphologic Assessment

Organizers:Lorenzo Mannelli, M.D., Ivan Pedrosa, M.D., Ph.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Nicoll 1 16:30 - 18:30 Moderators:Sooah Kim & S. Sendhil Velan

16:30
Introduction by Moderator

16:33
Arterial Spin Labeled Measurement of Renal Perfusion
Ananth J Madhuranthakam1

1Radiology, UT Southwestern Medical Center, Dallas, TX, United States

ASL has become a mainstream application for brain perfusion, but still has challenges for renal perfusion. Various improvements including pseudo-continuous labeling combined with background suppression and timed-breathing approaches have enabled robust renal perfusion imaging. This presentation will discuss different types of arterial spin labeling technique along with the acquisition methods and strategies for robust renal perfusion imaging without the administration of exogeneous contrast agent.  

267 16:48
Assessing longitudinal renal blood flow changes in children following renal replacement therapy using Arterial Spin Labelling MRI
Fábio Nery1, Enrico De Vita2,3, Chris A. Clark1, Isky Gordon1, and David L. Thomas3

1UCL Institute of Child Health, Developmental Imaging and Biophysics Section, LONDON, United Kingdom, 2National Hospital for Neurology and Neurosurgery, Lysholm Department of Neuroradiology, LONDON, United Kingdom, 3UCL Institute of Neurology, Department of Brain Repair and Rehabilitation, LONDON, United Kingdom

Arterial spin labelling (ASL) is a contrast-free MRI technique that allows for the quantitative measurement of organ perfusion. In this study, we non-invasively evaluated renal perfusion changes in sixteen children within the first year following renal replacement therapy using ASL. Each child was scanned in three occasions : (A) immediately post-transplant; (B) “1 month” post-transplant and (C) “1 year” post-transplant. The highest renal cortical blood flow was seen on the first scan in the majority of children while in later scans equilibrium between child and kidney was reached. 


268 17:00
Noninvasive Measurement of Single Renal Oxygen Extraction Fraction using Focused Asymmetric Spin Echo Approach - a feasibility study
CY Wang1, R Zhang2, L Jiang3, R Wang4, XD Zhang4, H Wang3, K Zhao4, LX Jin3, J Zhang1,2, XY Wang1,4, and J Fang1,2

1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, People's Republic of, 2College of Engineering, Peking University, Beijing, China, People's Republic of, 3Philips Healthcare, Suzhou, China, People's Republic of, 4Department of Radiology, Peking University First Hospital, Beijing, China, People's Republic of

This study demonstrates the feasibility of combining 2D-RF excitation pulse and ASE sequence (focused ASE sequence, FASE) for single renal OEF measurement. Comparison between images acquired with full-FOV ASE and focused ASE was conducted to confirm the advantages of the focused ASE sequence for single renal imaging.  The new technique could reduce artifacts and distortion caused by susceptibility differences, and limit spatial blurring due to T2-decay, which is promising for diagnosis of some renal diseases.

17:12
How Bold is BOLD MRI of the Kidney: Detailing Renal Hypoxia with MRI, Electrochemical Physiological Methods and Optical Imaging
Thoralf Niendorf1

1Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Berlin

This presentation is designed to inspire the preclinical and clinical imaging, renal physiology, and nephrology communities to foster explorations into the assessment of renal oxygenation and haemodynamics by exploiting the powers of MRI. For this purpose the merits and limitations of renal BOLD-MRI are surveyed together with their implications. Explorations into detailing the relation between renal T2* and renal tissue partial pressure of oxygen (pO2) are discussed. Multi-modality in vivo approaches suitable for detailing the role of the confounding factors that govern T2* are considered. Future directions of MRI assessment of renal oxygenation and perfusion are explored.


 

269 17:27
Quantitative MRI of Renal Function in a Mouse Model of Unilateral Ureteral Obstruction
Haiying Tang1, Matthew Fronheiser1, Guoqiang Zhang2, Adrienne Pena1, Daniel Kukral1, Cindy Cai2, Rachel Zebo2, Jeff L L Zhang3, Bradley Zinker2, Anthony Azzara2, Patrick Chow1, Feng Luo4, and Wendy Hayes1

1Bristol Myers Squibb, Princeton, NJ, United States, 2Bristol Myers Squibb, Hopewell, NJ, United States, 3Radiology, University of Utah, Salt Lake City, UT, United States, 4Bristol Myers Squibb, Wallingford, CT, United States

Recent advances in magnetic resonance imaging (MRI) allow the development of non-invasive and quantitative tools to assess renal function. DCE-MRI using low dose Gd-based contrast has been established as a reliable technique for measuring glomerular filtration rate (GFR) in individual kidneys. Other promising markers for renal function include R2* measured with BOLD MRI, and the longitudinal relaxation time T1. Unilateral ureteral obstruction (UUO) has been developed in rodents as a model of renal fibrosis. The purpose of the study is to evaluate the various MRI techniques in assessing kidney tissue properties and renal function in the UUO mouse model.

270
17:39
Determination of Parameters Variation in DTI, BOLD, and ASL MRI for Transplanted Kidneys
Maryam Seif1, Laila Yasmin Mani2, Chris Boesch1, Bruno Vogt2, and Peter Vermathen1

1Depts. Radiology and Clinical Research, University of Bern, Bern, Switzerland, 2Dept. Nephrology, Hypertension and Clinical Pharmacology, Hospital University of Bern, Bern, Switzerland

DTI, BOLD and ASL MRI techniques have gained acceptance to evaluate different physiological aspects of the renal function both in research and clinics. However, there are not yet sufficient studies available investigating the accuracy and repeatability of renal MRI techniques. The main aim of this study was therefore to evaluate the reproducibility of DTI, BOLD MRI and ASL parameters derived from two scans and to investigate whether there are significant correlations  between renal parameters obtained from these MR techniques in transplanted kidneys.

17:51
Diffusion
Hersh Chandarana1

1NYU School of Medicine

Conventional methods of measuring renal function including estimated GFR are insensitive to early renal dysfunction and cannot assess single kidney function/dysfunction. Advance MR imaging techniques including diffusion weighted imaging (DWI) are being investigated to study renal microstructure and function in health and disease. Various flavors of diffusion weighted imaging including intra-voxel incoherent motion (IVIM) and diffusion tensor imaging (DTI) have shown considerable promise in evaluation of kidney structure and function. 

271 18:06
Diffusion Tensor Imaging (DTI) of the kidneys incorporating advanced geometric distortion correction using reversed phase encoding images.
Jose Teruel1,2, Jeremy C. Lim3, Eric E. Sigmund4, Elissa Botterill5, Jas-mine Seah6, Shawna Farquharson7, Elif E. Ekinci6,8, and Ruth P. Lim5,9

1Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway, 2St. Olavs University Hospital, Trondheim, Norway, 3Department of Radiology, The Royal Melbourne Hospital, Melbourne, Australia, 4Department of Radiology, NYU Langone Medical Center, New York, NY, United States, 5Department of Radiology, Austin Health, Melbourne, Australia, 6Department of Endocrinology, Austin Health, Melbourne, Australia, 7Florey Neuroscience Institute, Melbourne, Australia, 8Department of Endocrinology, The University of Melbourne, Melbourne, Australia, 9Departments of Radiology and Surgery, The University of Melbourne, Melbourne, Australia

Diffusion tensor imaging is emerging as a promising technique for structural and functional evaluation of the kidneys. However, diffusion sequences employing echo planar imaging readout are prone to geometric distortions due to static field inhomogeneities arising from different magnetic susceptibilities from adjacent tissues and bowel gas. In this study, we evaluated the efficacy of distortion correction using a reversed phase encoding approach for diffusion tensor imaging of healthy controls and patients with Type 1 diabetes.

272 18:18
Kidney diffusion-weighted imaging based on multi-band multi-shot DW-EPI acquisition and multi-band multiplexed sensitivity encoding (MB-MUSE) reconstruction
Hing-Chiu Chang1,2, Arnaud Guidon3, Mustafa R. Bashir4, Dan Xu5, Lloyd Estkowski6, Ersin Bayram7, Allen W. Song2, and Nan-Kuei Chen2

1Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong, Hong Kong, 2Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC, United States, 3Global MR Application and Workflow, GE Healthcare, Boston, MA, United States, 4Department of Radiology, Duke University Medical Center, Durham, NC, United States, 5Global MR Application and Workflow, GE Healthcare, Waukesha, WI, United States, 6Global MR Application and Workflow, GE Healthcare, Menlo Park, CA, United States, 7Global MR Application and Workflow, GE Healthcare, Houston, TX, United States

DWI has been shown to be useful in characterizing renal carcinoma with quantitative measurement of ADC. However, with echo-planar imaging (EPI) based DWI protocols, the application of body DWI remains limited due to suboptimal EPI image quality. The multi-band multi-shot EPI with multiplexed sensitivity encoding (MB-MUSE) has been developed and shown to be useful in achieving high-resolution and high-quality DWI and DTI of brains, with improved scan throughput. In this study, we propose to use MB multi-shot EPI to acquire kidney DWI data with reduced geometric distortion and bilateral coverage, demonstrating the feasibility of MB multi-shot DWI of body applications.

18:30
Adjournment & Meet the Teachers


Educational Course

Cardiac MRI: Non-Ischemic Cardiomyopathies

Organizers:Daniel Ennis, Ph.D. & Martin Graves, Ph.D.

Nicoll 2 16:30 - 18:30 Moderators:Harald Kramer & Jeanette Schulz-Menger

16:30
CMR in Inflammatory Systemic Disorders
Andrew Taylor1,2

1Department of Cardiovascular Medicine, Alfred Hospital, Melbourne, Australia, 2BakerIDI Heart and Diabetes Institute, Melbourne, Australia

Cardiac manifestations are frequently observed in many inflammatory systemic disorders. Identification of cardiac involvement is of high clinical importance, as in many instances a large proportion of the morbidity and mortality in systemic inflammatory diseases is due to cardiac complications, which if identified early may be amenable to therapeutic intervention. In order to simplify the protean cardiac manifestations observed in inflammatory systemic disorders, these diseases can be discussed under the general headings of sarcoidosis, connective tissue diseases, and hypereosinophilic syndromes.

17:00
CMR for Identification of Secondary Left Ventricular Hypertrophy  
Marianna Fontana1

1University College London


17:30
CMR in Metabolic Disorders
Harald Kramer1

1University Hospital Munich

Besides particular cardiac disease like congenital heart disease, ischemic heart disease or myocarditis the heart can be involved in numerous systemic disease entities. These include endstage kidney disease, liver cirrhosis, metabolic syndrome, amyloidosis, autoimmune disorders, hereditary metabolic defects and malignant disease.  Cardiac involvement can include coronary artery disease, valvular disease, endocardial, myocardial or pericardial disorders. Detailed knowledge of the potential cardiac alterations in systemic disease is key in their accurate diagnosis and treatment. 

18:00
CMR in Genetic Disorders
Bernd J. Wintersperger1

1Department of Medical Imaging, University of Toronto, Toronto, ON, Canada

Continuous discoveries in genome abnormities result in an ever increasing number of cardiovascular diseases being considered of genetic cause. High importance is furthermore emphasis of either heritable disease or individual mutation caused abnormality. While beyond assessment of genomics, the versatile toolbox of cardiac MRI enables detailed insight into subtle phenotypes that may be linked to changes in genotype (genotype +) and as such provides insight into a possible clinical course of a disease. Furthermore, cardiac MRI provides ongoing excellence in the important aspect of initial diagnosis, therapy monitoring and identification of possible complications in a large variety of genetic CV diseases.

18:30
Adjournment & Meet the Teachers


Educational Course

MR Physics & Techniques for Clinicians

Organizers:Marcus T. Alley, Ph.D., Brian Hargreaves, Ph.D., Michael Markl, Ph.D., Bernd Jung, Ph.D. & Nicole Seiberlich, Ph.D.

Nicoll 3 16:30 - 18:30 Moderators:Vikas Gulani & Bernd Jung

16:30
Spin Gymnastics
Walter Kucharczyk

Spin Gymnastics is both an introduction to MRI physics and a summary of its most important concepts. It is intended to "set the table" for a series of subsequent lectures in the Physics for Clinicians Course that build on the basic concepts presented in this lecture. The information is presented in a graphical, animated format to assist in the complex understanding of the spatial and temporal components of the MR imaging process.

17:00
K-Space
Rafael O'Halloran1

1Icahn School of Medicine at Mount Sinai

We will take a graphical approach to review key concepts of k-space as they relate to MRI image quality. Using cartoons and images we will demonstrate how resolution, field-of-view, and SNR can be understood in terms of k-space coverage and sampling. The implications on image quality will be discussed and demonstrated with example images.

17:30
Adjournment & Meet the Teachers


Study Groups

Molecular & Cellular Imaging

Hall 406 D 18:45 - 20:45


Gold Corporate Symposium

Gold Corporate Symposium: GE Healthcare

Plenary Hall 13:00 - 14:00


Other

Special Session: Manuscript Reviewing for ISMRM’s Scientific Journals

Room 300-302 18:45 - 19:45



Tuesday, May 10, 2016

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Sunrise Session

Multiparametric MR for Cancer

Organizers:Guanshu Liu, Ph.D. & Mark D. Pagel, Ph.D.

Room 300-302 7:00 - 7:50 Moderators:Rosella Canese & Katja Pinker

Tumor Diagnosis with MR Spectroscopy.
Arend Heerschap

MRS - Response to Therapy
Tone Frost Bathen

Adjournment & Meet the Teachers


Sunrise Session

High-Throughput: The 5 Minute MR Scan

Organizers:Garry E. Gold, M.D. & Joshua D. Trzasko, Ph.D.

Room 324-326 7:00 - 7:50 Moderators:Joshua Trzasko

Cardiac MRI
Daniel Sodickson

MR Angiography
Tim Leiner

Adjournment & Meet the Teachers


Sunrise Session

Addressing Clinical Challenges in the Body with MRI: Incidental Cystic Lesions

Organizers: Ivan Pedrosa, M.D., Lorenzo Mannelli, M.D., Ph.D., Scott B. Reeder, M.D., Ph.D. & Edwin J.R. van Beek, M.D., Ph.D., M.Ed., FRCR

Room 331-332 7:00 - 7:50 Moderators:Mustafa Bashir

A Guideline Based Approach to the Incidental Pancreatic Cysts
Masoom Haider

Incidental Cystic Lesions: Kidney
Kartik Jhaveri

Adjournment & Meet the Teachers


Sunrise Session

Techniques for Imaging White Matter

Organizers:Andrew Alexander, Ph.D. & Jennifer A McNab, Ph.D.

Room 334-336 7:00 - 7:50 Moderators:Cornelia Laule

White Matter Imaging: Established Techniques
Mara Cercignani

White Matter Imaging: Emerging Techniques
Susie Huang

Adjournment & Meet the Teachers


Sunrise Session

Interventional MRI: Technology

Organizers:Michael S. Hansen, Ph.D. & Viola Rieke, Ph.D.

Summit 1 7:00 - 7:50 Moderators:Michael Hansen

Introduction

The Interventional MRI Suite
Anthony Faranesh

Real-Time Image Guidance
Adrienne Campbell-Washburn

Adjournment & Meet the Teachers


Sunrise Session

Hyperpolarisation & MR Applications

Organizers:Thomas K. F. Foo, Ph.D. & N. Jon Shah, Ph.D.

Summit 2 7:00 - 7:50 Moderators:Sean Fain & Philip Lee


Sunrise Session

Ultra-High Field Cardiovascular MRI

Organizers:Harald Kramer, M.D. & Jeanette Schulz-Menger, M.D.

Nicoll 1 7:00 - 7:50 Moderators:Harald Kramer & Jeanette Schulz-Menger

Vascular MR at 7T
Harald H. Quick

Cardiac Spectroscopy at 7T
Christopher Rodgers

Morphological Cardiac MR at 7T
Thoralf Niendorf

Adjournment & Meet the Teachers


Sunrise Session

Advanced Quantitative MSK Imaging Techniques

Organizers:Jenny T. Bencardino, M.D., Eric Y. Chang, M.D., Christine Chung, M.D., Ravinder R. Regatte, Ph.D., Philip Robinson, M.D. & Siegfried Trattnig, M.D.

Nicoll 2 7:00 - 7:50 Moderators:Eric Chang & Ashley Williams


Sunrise Session

Controversies in Diffusion & Functional MRI

Organizers:Daniel C. Alexander, Ph.D., Jay J. Pillai, M.D. & Jonathan R. Polimeni, Ph.D.

Nicoll 3 7:00 - 7:50 Moderators:Daniel Alexander

Microstructural Features Accessible from Diffusion MRI
Sune Jespersen

Benefits of a Multimodal Approach
Nikola Stikov

Adjournment & Meet the Teachers


Plenary Session

MRI Biomarkers: Paradigm Shift or Contradiction in Terms?

Organizers:Steven P. Sourbron, Ph.D., Guoying Liu, Ph.D. & Garry E. Gold, M.D.

Plenary Hall 8:30 - 9:30 Moderators:Steven Sourbron & Guoying Liu

The Quantitative Imaging Biomarkers Alliance (QIBA)
Daniel C Sullivan1

1Radiology, Duke University Medical Center, Durham, NC, United States
Daniel Sullivan

Reproducibility & Standardisation of MR Biomarkers
Edward F Jackson1

1Medical Physics, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States
Edward Jackson

Integration of MRI Biomarkers into Radiology Practice
Nandita deSouza1

1The Institute of Cancer Research, London, UK
Nandita deSouza

Adjournment


Traditional Poster : Body

Exhibition Hall 10:00 - 12:00 (no CME credit)

Electronic Poster : Acquisition, Reconstruction & Analysis

Exhibition Hall 10:00 - 11:00 (no CME credit)

Study Groups

Musculoskeletal MR

Hall 405 E 10:00 - 12:00


Study Groups

X-Nuclei Imaging

Hall 406 D 10:00 - 12:00


Power Pitch

Neuroimaging: Novel Findings & Techniques

Power Pitch Theatre, Exhibition Hall 10:00 - 11:00 Moderators:Peter Barker & Peter Bandettini

273
10:00
Simultaneous evaluation of hemodynamic and functional connectivity in patients with chronic steno-occlusive disease of the cerebrovascular system: A study using BOLD with acetazolamide
Junjie Wu1, Seena Dehkharghani1, Tyler Gleason1, Fadi Nahab2, and Deqiang Qiu1

1Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States, 2Department of Neurology, Emory University, Atlanta, GA, United States

274 10:03
Electrical Conductivity Characteristics of Glioma: Noninvasive Assessment by MRI and Its Validity
Khin Khin Tha1,2, Ulrich Katscher3, Shigeru Yamaguchi4, Shunsuke Terasaka4, Toru Yamamoto5, Kohsuke Kudo2,6, and Hiroki Shirato1,2

1Department of Radiobiology and Medical Engineering, Hokkaido University Graduate School of Medicine, Sapporo, Japan, 2Global Institution for Quantum Medical Science and Engineering, Hokkaido University, Sapporo, Japan, 3Research Laboratories, Hamburg, Germany, 4Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan, 5Graduate School of Health Sciences, Sapporo, Japan, 6Hokkaido University Hospital, Sapporo, Japan

275
10:06
Quantifying differences in the cerebral blood flow (CBF) between controls, professional boxers and Mixed Martial Arts (MMA) fighters using arterial spin labeling (ASL) MRI
Virendra R Mishra1, Karthik Sreenivasan1, Xiaowei Zhuang1, Zhengshi Yang1, Sarah Banks1, Dietmar Cordes1, and Charles Bernick1

1Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV, United States

276 10:09
The Evolution of the Mammalian Connectome
Yossi Yovel1, Omri Zomet1, Arieli Bonzach2, Assaf Marom1, and Yaniv Assaf1

1Tel Aviv University, Tel Aviv, Israel, 2Beit Dagan Veterinary institute, Beit Dagan, Israel

277
10:12
Neurite Orientation Dispersion and Density Imaging (NODDI) in Young Onset Alzheimer's Disease and Its Syndromic Variants
Jiaying Zhang1, Catherine F Slattery2, Ross W Paterson2, Alexander JM Foulkes2, Laura Mancini2, David L Thomas2, Marc Modat1, Nicolas Toussaint2, David M Cash2, John S Thornton2, Daniel C Alexander1, Sebastien Ourselin1, Nick C Fox2, Jonathan M Schott2, and Hui Zhang1

1Department of Computer Science and Centre for medical image computing, University College London, London, United Kingdom, 2Department of Neurodegenerative disease, Institute of Neurology, University College London, London, United Kingdom

278 10:15
Developmental processes on the neonatal brain revealed by white matter tract integrity metrics derived from diffusion kurtosis imaging
Xianjun Li1,2, Jie Gao1, Yumiao Zhang1, Yanyan Li1, Huan Li1, Mingxi Wan2, and Jian Yang1,2

1Radiology Department of the First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China, People's Republic of, 2Department of Biomedical Engineering, the Key Laboratory of Biomedical Information Engineering of the Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China, People's Republic of

279
10:18
A serial microcompartment-specific T2* relaxation study of white matter lesions in multiple sclerosis at 7T
Xiaozhen Li1,2, Peter van Gelderen2, Pascal Sati3, Jacco de Zwart2, Daniel Reich3, and Jeff Duyn2

1Dept. NVS, Karolinska Institutet, Stockholm, Sweden, 2Advanced MRI Section, LFMI, NINDS, National Institutes of Health, Bethesda, MD, United States, 3Translational Neuroradiology Unit, NINDS, National Institutes of Health, Bethesda, MD, United States

280 10:21
Real-time fMRI Neurofeedback with Simultaneous EEG in Combat-related PTSD: Frontal EEG Asymmetry Variations as Measure of Treatment Response
Vadim Zotev1, Raquel Phillips1, Masaya Misaki1, Chung Ki Wong1, Brent Wurfel1, Matthew Meyer1,2, Frank Krueger1,3, Matthew Feldner1,4, and Jerzy Bodurka1,5

1Laureate Institute for Brain Research, Tulsa, OK, United States, 2Laureate Psychiatric Clinic and Hospital, Tulsa, OK, United States, 3Neuroscience Dept., George Mason University, Fairfax, VA, United States, 4Dept. of Psychological Science, University of Arkansas, Fayetteville, AR, United States, 5College of Engineering, University of Oklahoma, Tulsa, OK, United States

281
10:24
In-vivo detection of neuronal current using spin-lock oscillatory excitation at 7T
Yuhui Chai1, Guoqiang Bi2, Liping Wang3, Fuqiang Xu4, Xin Zhou4, Bensheng Qiu2, Hao Lei4, Bing Wu5, Yang Fan5, and Jia-Hong Gao1

1Center for MRI Research, Peking University, Beijing, China, People's Republic of, 2University of Science and Technology of China, Hefei, China, People's Republic of, 3Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, People's Republic of, 4Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China, People's Republic of, 5GE Healthcare, MR Research China, Beijing, China, People's Republic of

282
10:27
Rapid Myelin Water Imaging in Human Cervical Spinal Cord
Emil Ljungberg1, Irene Vavasour2, Roger Tam2,3, Youngjin Yoo3, Alexander Rauscher4, David Li2, Anthony Traboulsee5, Alex MacKay1,2, and Shannon Kolind5

1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2Radiology, University of British Columbia, Vancouver, BC, Canada, 3Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada, 4Pediatrics, University of British Columbia, Vancouver, BC, Canada, 5Medicine, University of British Columbia, Vancouver, BC, Canada

283
10:30
Transcranial MRI-Guided High-Intensity Focused Ultrasound for Treatment of 
Essential Tremor: Initial Clinical Experience and Correlation of Clinical Outcome with Lesion Size, Localization, and Dose
Christian Federau1, Maged Goubran1, Jason Su1, Jaimie Henderson1, Veronika Santini1, Casey Harrison Halpern1, Brian Rutt1, Kim Butts Pauly1, and Pejman Ghanouni1

1Stanford University, Stanford, CA, United States

284 10:33
Neuroimaging of Acute Ebola Virus Disease in a Non-Human Primate Model
Margaret R. Lentz1, Jeffery R. Solomon2, Srikanth Yellayi1, Richard Bennett1, Dawn Traynor1, David Thomasson1, Anna Honko1, Lisa Hensley1, and Peter B. Jahrling1,3

1Integrated Research Facility, NIAID, National Institutes of Health, Frederick, MD, United States, 2Clinical Research Directorate/Clinical Monitoring Research Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, MD, United States, 3Emerging Viral Pathogens Section, NIAID, National Institutes of Health, Frederick, MD, United States

285 10:36
Structural variability in the human brain reflects functional architecture
Gwenaelle Douaud1, Eugene Duff1, Adrian Groves1, Thomas Nichols1,2, Saad Jbabdi1, Christian Tamnes3, Lars Westlye3, Andreas Engvig3, Kristine Walhovd3, Anders Fjell3, Heidi Johansen-Berg1, and Steve Smith1

1FMRIB Centre, University of Oxford, Oxford, United Kingdom, 2University of Warwick, Coventry, United Kingdom, 3University of Oslo, Oslo, Norway

286
10:39
A constrained slice-dependent background suppression scheme for simultaneous multi-slice pseudo-continuous arterial spin labeling
Xingfeng Shao1, Yi Wang1, and Danny J.J. Wang1

1Laboratory of FMRI Technology (LOFT), Department of Neurology, University of California Los Angeles, Los Angeles, CA, United States

287 10:42
Brain Catalogue and its MRI of extinct species: the example of Thylacinus Cynocephalus
Mathieu David Santin1,2, Marc Herbin3, and Roberto Toro4

1Centre de NeuroImagerie de Recherche - CENIR, Paris, France, 2Inserm 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, 3Muséum National d'Histoire Naturelle, Paris, France, 4Institut Pasteur, Paris, France


Oral

Radiogenomics & Radiomics

Room 300-302 10:00 - 12:00 Moderators:Seung Hong Choi & Radka Stoyanova

10:00
Introduction

288
10:12
Radiogenomic analysis of glioblastoma using protein-based amide proton transfer (APT) imaging and message RNA expression: A novel correlation in molecular imaging and gene characteristics
Shanshan Jiang1, Xianlong Wang1, Hao Yu1, Jiandong Xi1, Jingwen Wu1, Lisong Liang1, Shilong Lu1, Tianyu Zou1, Jinyuan Zhou2, and Zhibo Wen1

1Department of Radiology, Southern Medical University Zhujiang Hospital, Guangzhou, China, People's Republic of, 2Department of Radiology, Johns Hopkins University, Baltimore, MD, United States

The correlation between endogenous protein-based APT-weighted (APTw) imaging and gene expression in glioblastoma (GBM) was investigated. 16 patients with newly diagnosed GBM were studied. APTw/FLAIR hyperintensity area ratio (AFR), and APTw hyperintensity/gadolinium contrast-enhanced T1w enhancement area ratio (ATR) were calculated. Interoperative paired tumor and adjacent normal tissues were sampled for genomic analysis. BRCA1 and CDK4 were significantly downregulated in the high AFR group (adjusted P= 0.000953 and 0.025187), and SLAMF9 and MIA were significantly downregulated in the high ATR group (adjusted P= 1.08E-11 and 0.00997). APT imaging has great potential for unveiling some special genomic changes in GBM.

289 10:24
Large-scale radiomic profiling of glioblastoma identifies an imaging signature for predicting and stratifying antiangiogenic treatment response.
Philipp Kickingereder1, Michael Götz2, John Muschelli3, Antje Wick4, Ulf Neuberger5, Russell T Shinohara6, Alexander Radbruch7, Heinz-Peter Schlemmer7, Wolfgang Wick4, Martin Bendszus5, Klaus H Maier-Hein2, and David Bonekamp7

1Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany, 2Division Medical and Biological Informatics, DKFZ - German Cancer Research Center, Heidelberg, Germany, 3Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States, 4Department of Neurology, University of Heidelberg Medical Center, Heidelberg, Germany, 5Department of Neuroradiology, University of Heidelberg Medical Center, Heidelberg, Germany, 6Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States, 7Department of Radiology, DKFZ - German Cancer Research Center, Heidelberg, Germany

To analyze the potential of radiomics, an emerging field of research that aims to utilize the full potential of medical Imaging (1,2), for predicting and stratifying treatment response to antiangiogenic therapy in patients with recurrent glioblastoma.  

290 10:36
Low Apparent Diffusion Coefficient Values Correlate with Enhancing Mitosis and Cell Proliferation Expression in glioblastoma using Locus-Specific Radiogenomic Map
Cheng-Yu Chen1,2,3, Fei-Ting Hsu1, Hua-Shan Liu1,4, Ping-Huei Tsai1,3, Chia-Feng Lu2,3,5, Yu-Chieh Kao2,3, Li-Chun Hsieh1, and Pen-Yuan Liao1

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

A new approach to unravel the genomic expression of glioblastoma by advanced MR imaging technique has recently been introduced to improve the prognostic and predictive efficacies of neuroimaging. This imaging method is potentially a valuable tool to link individual differences in the human genome to structure, function and physiology into brain disease, a method referred to as radiogenomics. In this study, we established locus specific radiogenomic map based on MR imaging and Microarray RNA analysis. Our results revealed that apparent diffusion coefficient (ADC) differences were correlated with several biological processes change, including cell proliferation, T cell immunity, immune response, and mitosis. The identification of tumor genotypes by imaging phenotypes will open a new era of therapeutic strategy in high grade gliomas.

291 10:48
Radiomic features on Multi-parametric MRI can help risk categorization of Prostate Cancer patients on Active Surveillance
Ahmad Algohary1, Satish Viswanath1, Sadhna Verma2, and Anant Madabhushi1

1Case Western Reserve University, Cleveland, OH, United States, 2University of Cincinnati, Cincinnati, OH, United States

Active Surveillance (AS) offers an important alternative to radical treatment as more men die with prostate cancer (PCA) than of the disease. In this study, we explore the role of radiomic texture features on a pre-biopsy screening 3 Tesla multi-parametric MRI that can predict which men with elevated PSA will have a cancer-positive or cancer-negative biopsy. The selected texture features correctly identified 14/15 biopsy-negative (compared to 10/15 cases correctly identified by PIRADS) and 23/30 biopsy-positive cases (compared to only 15/30 correctly identified by PIRADS). These features appear to enhance differentiation between biopsy-positive and biopsy-negative prostate cancer patients on Active Surveillance.

292 11:00
Association of Radiomics and Metabolic Tumor Volumes in Radiation Treatment of Glioblastoma Multiforme
christopher lopez1, Natalya Nagornaya2, Nestor Parra2, Deukwoo Kwon2, Fazilat Ishkanian2, Arnold Markoe2, Andrew Maudsley2, and Radka Stoyanova2

1Radiation Oncology, University of Miami, Miami, FL, United States, 2University of Miami, Miami, FL, United States

To investigate the importance of metabolites of N-acetyl aspartate and choline derived from MRSI and the correlation of image features from localized radiation therapy volumes determined from MRI and CT defined tumor volumes. Also to replace subjective categorical image features with calculated objective features. Results suggest that radiation therapy planning can be more accurate by adding metabolic information.

293 11:12
Relationship of invivo MR parameters to molecular characteristics of non-enhancing lower-grade gliomas
Tracy L Luks1, Tracy Richmond McKnight1, Aurelia Williams1, Evan Neill1, Khadjia Lobo1, Anders Persson2, Arie Perry3, Joanna Phillips3, Annette Molinaro4, Susan Chang4, and Sarah J Nelson1

1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 2Neurology, University of California San Francisco, San Francisco, CA, United States, 3Pathology, University of California San Francisco, San Francisco, CA, United States, 4Neurosurgery, University of California San Francisco, San Francisco, CA, United States

Invivo MR anatomy, diffusion, perfusion, and spectroscopy profiles from non-enhancing grade 2 and grade 3 gliomas were examined by histologic and molecular characteristics associated with clinical outcome. Patients underwent a pre-surgical 3T MR exam including IRSPGR, FSE, FLAIR, DWI, MRSI and DSC. For surgical biopsies, histological sub-type, grade, cleaved caspase-3, MIB-1, Ki67, IDH1R132H, ATRX, p53, and co-deletion of 1p19q were determined. Overall, molecular characteristics associated with worse clinical outcome were associated with higher ADC and lower FA, lower nCBV and nPH, and higher Recov, and higher nLAC.

294 11:24
Radiomic features from the necrotic region on post-treatment Gadolinium T1w MRI appear to differentiate pseudo-progression from true tumor progression in primary brain tumors
Prateek Prasanna1, Raymond Huang2, Andrew Rose1, Gagandeep Singh1, Anant Madabhushi1, and Pallavi Tiwari1

1Case Western Reserve University, Cleveland, OH, United States, 2Brigham and Women's Hospital, Boston, MA, United States

Pseudoprogression is an early-delayed inflammatory response to chemoradiotherapy typically appearing up to 3 months post-treatment in brain tumors. On routine MRI, pseudoprogression closely mimics the appearance of true progression, thereby making their visual identification challenging. Early diagnosis of pseudoprogression has implications in management of treatment effects and subsequently survival. We present initial results of using a newly developed radiomic descriptor, CoLlAGE, in distinguishing the two pathologies. We report that CoLlAGe measurements when captured from the necrotic region as opposed to just the enhancing region on MRI can reliably distinguish psuedo-progression from true progression with 100% accuracy (n=17)

295 11:36
Combined assessment of tumor oxygen metabolism and angiogenesis in glioma patients
Andreas Stadlbauer1, Max Zimmermann1, Karl Rössler1, Stefan Oberndorfer2, Arnd Dörfler3, Michael Buchfelder1, and Gertraud Heinz4

1Department of Neurosurgery, University of Erlangen, Erlangen, Germany, 2Department of Neurology, University Clinic of St. Pölten, St. Pölten, Austria, 3Department of Neuroradiology, University of Erlangen, Erlangen, Germany, 4Department of Radiology, University Clinic of St. Pölten, St. Pölten, Austria

Reprogramming energy metabolism and inducing angiogenesis are part of the hallmarks of cancer. Thirty-five patients with untreated or recurrent glioma were examined using vascular architecture mapping (VAM) and the multiparametric quantitative BOLD (mp-qBOLD) technique for combined exanimation of oxygen metabolism and angiogenesis in gliomas. Maps of oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) as well as of the vascular architecture MRI biomarkers microvessel radius (RU), density (NU), and type indicator (MTI) were calculated. Low-grade glioma showed increased OEF. Glioblastomas showed significantly increased CMRO2 and NU. MTI demonstrated widespread areas draining venous microvasculature in high-grade gliomas.

296 11:48
Radiogenomics by Proton Magnetic Resonance Spectroscopy: Integrative Analysis of Metabolites and Genome-wide Expression in Glioblastomas
Dieter Henrik Heiland1, Thomas Lange2, Ralf Schwarzwald3, Dietmar Pfeifer4, Karl Egger3, Horst Urbach3, Astrid Weyerbrock1, and Irina Mader3

1Dept. of Neurosurgery, University Medical Center Freiburg, Freiburg, Germany, 2Dept. MR Physics, Dept. of Radiology, University Medical Center Freiburg, Freiburg, Germany, 3Dept. of Neuroradiology, University Medical Center Freiburg, Freiburg, Germany, 4Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center Freiburg, Freiburg, Germany

The purpose of this work was to search for a connection between metabolites observed by proton magnetic resonance spectroscopy of glioblastomas and tumor genetics. Two specific pathways could be identified, one belonging to NAA and discriminating an astroglial versus oligo/neural subgroup. Another one was related to Cr also distinguishing between two subgroups, one attributed to apoptosis and another one to the PI3K-AKT-mTOR signaling cascade.  


Oral

New Techniques for CEST & MT

Room 324-326 10:00 - 12:00 Moderators:Julio Cardenas & Phillip Zhe Sun

297
10:00
Simultaneous Multi-Slice Spiral-CEST Encoding with Hankel Subspace Learning: ultrafast whole-brain z-spectrum acquisition
Suhyung Park1, Sugil Kim1,2, and Jaeseok Park3

1Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon, Korea, Republic of, 2Department of Brain and Cognitive Engineering, Korea University, Seoul, Korea, Republic of, 3Department of Biomedical Engineering, Sungkyunkwan University, Suwon, Korea, Republic of

Chemical exchange saturation transfer (CEST) imaging has been introduced as a new contrast mechanism for molecular imaging, and typically requires long saturation preparation and multiple acquisitions of imaging data with varying saturation frequencies (called z-spectrum). Since the z-spectrum acquisition is inherently slow and takes prohibitively long imaging time, it has been very difficult to introduce CEST z-spectrum into a clinical routine. In this work, we propose a novel, simultaneous multi-slice (SMS) Spiral CEST encoding with Hankel subspace learning (HSL) for ultrafast whole-brain z-spectrum acquisition within 2-3 minutes, in which: 1) RF segmented uneven saturation is employed to reduce the duration of saturation preparation, 2) Spiral CEST encoding is employed to acquire SMS signals, and 3) SMS signals are projected onto the subspace spanned by the complementary null space, selectively reconstructing a slice of interest while nulling the other slice signals. 

298 10:12
Superfast CEST Spectral Imaging (SCSI)
Iris Yuwen Zhou1, Jinsuh Kim2, Takahiro Igarashi1, Lingyi Wen1, and Phillip Zhe Sun1

1Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States, 2Department of Radiology, University of Illusions at Chicago, Chicago, IL, United States

To resolve metabolites at different chemical shift offsets, complete Z-spectrum is conventionally obtained by varying saturation offset from scan to scan, which is time consuming and not suitable for studying dynamic changes. To overcome this, we innovatively combined superfast Z spectroscopy with chemical shift imaging (CSI) and developed Superfast Chemical exchange saturation transfer (CEST) Spectral Imaging (SCSI). It provides fast Z-spectral CEST information with spatial resolution. While conventional CSI measures dilute metabolites, the proposed SCSI exploits CEST mechanism to investigate the interaction between metabolites/contrast agents and tissue water, providing sensitivity enhanced measurements of metabolites and pH information.

299 10:24
Clinically relevant rapid 3D CEST imaging with hexagonal spoiling gradients, optimised B1, and symmetric z-spectrum sampling
Robert C. Brand1, Nicholas P. Blockley1, Michael Chappell2, and Peter Jezzard1

1FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom, 2IBME, University of Oxford, Oxford, United Kingdom

Clinical 3D CEST has been hindered by slow acquisition times and z-spectra artefacts that affect fitting. Here, we demonstrate various sequence improvements, including: 1) hexagonal gradient spoiling that minimises ghosting, shortens TR and reduces confounding T2 sensitivity; 2) low readout flip angles combined with symmetric z-spectrum sampling that better maintains the steady state between samples and eliminates the need for T1-restoration periods; and 3) exchange-rate matched 360° CEST pulses that reduce direct water saturation to minimise T1 sensitivity and increase CNR. Together, these improvements result in high-quality whole-brain 39-offset z-spectra measurements at 3mm isotropic resolution in 2:59 minutes.

300 10:36
Conjoint measure of 3D ASL and 3D APT in the lesion proximal regions for differentiating metastasis tumor from glioblastom
Rui Li1, Bing Wu2, Chien-yuan Lin3, Xin Lou1, YuLin Wang1, and Lin Ma1

1Department of Radiology, PLA general Hospital, Beijing, China, People's Republic of, 2GE healthcare MR Research China, Beijing, China, People's Republic of, 3GE heathcare Taiwan, Taipei, Taiwan

Differential diagnosis is challenging due to similar appearance using conventional imaging such as T1 contrast enhanced and DWI. In this work, we use the measure of spatially matching 3D arterial spin labeling (ASL) and 3D amide proton transfer (APT) in the lesion proximal regions to differentiate metastasis and glioblastom, in the hypothesis that glioblastom  infiltrates into sourrounding tissues whereas metastasis tumors have clear biological boundaries.

301
10:48
Blind Compressed Sensing-based Ultrafast Chemical Exchange Saturation Transfer (CEST) Imaging
Hye-Young Heo1,2, Sampada Bhave3, Mathews Jacob3, and Jinyuan Zhou1,2

1The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States, 3Department of Electrical and Computer Engineering, University of Iowa, Iowa City, IA, United States

CEST imaging, such as amide proton transfer (APT) imaging, is a novel, clinically valuable molecular MRI technique that can give contrast due to a change in water signal caused by chemical exchange with saturated solute protons. However, its clinical translation is still limited by its relatively long scan time because a series of RF saturation frequencies are unavoidably acquired. Here, we present a highly accelerated CEST imaging technique (up to 10-fold) using a novel blind compressed sensing framework.

302 11:00
Separation of intracellular and extracellular Z-spectra by DiffusionCEST
Kevin Ray1, Gogulan Karunanithy2, Andrew Baldwin2, Michael Chappell3, and Nicola Sibson1

1Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom, 2Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, United Kingdom, 3Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom

CEST-MRI is an imaging technique which is sensitive to tissue pH, and has generated pH-weighted images in acute stroke patients. One key assumption regarding CEST-MRI is that the signal is predominantly intracellular. This assumption has implications in the application of CEST-MRI for pH measurement of tumours, which are generally associated with extracellular acidosis. This study developed a novel pulse sequence, combining stimulated echo acquisition mode diffusion and CEST imaging. Using this novel pulse sequence, the intracellular and extracellular contributions to the acquired Z-spectrum were isolated in a simple cell system and post-mortem mouse brain.

303 11:12
Multi-echo Parametric VARiation Saturation (MePaVARS) enabling more specific endogeneous CEST imaging
Xiaolei Song1,2, Yan Bai1,3, Meiyun Wang3, and Michael T. McMahon1,2

1The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States, 3Department of Radiology, Henan Provincial People’s Hospital, Zhengzhou, China, People's Republic of

Existing CEST methodologies have difficulties in discriminating agents with small difference in chemical shift. As CEST signal is very sensitive to saturation power (B1) and length (tsat), indicating a second route to indentify agents by modulating the saturation conditions. We utilized the Multi-echo Parametric VARiation Saturation (MePaVARS), to separate faster and slower exchanging endogeneous CEST metabolites and molecules according to their differences response to B1. In simulations and phantoms, MePaVARS allowed extraction of faster-exchanging Glutamate from the slower-exchanging Creatine, based on its oscillation patterns. A preliminary study for mice bearing prostate tumor further validated the feasibility of MePaVARS in vivo

304 11:24
Implementing single-shot quantitative CEST/T1ρ measurements using bSSFPX
Shu Zhang1, Robert E Lenkinski1,2, and Elena Vinogradov1,2

1Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 2Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States

Recently properties of bSSFP were explored to detect exchange processes (bSSFPX), similar to CEST or off-resonance T experiments. We expand the study and implement a transient bSSFPX experiment that acquires bSSFP spectra continuously as the effective saturation time increases, allowing observation of the approach of magnetization to the steady state in a single shot. The magnetization dynamic is governed by the effective field and relaxation times parallel or perpendicular to it. Work is in progress to derive an exact quantification model. The method leads to fast acquisition of time-dependent data and may speed up QUEST-like quantification of the exchange processes.

305
11:36
IHMT: Is it misnamed? A simple theoretical description of "inhomogeneous" MT.
Alan P Manning1, Kimberley L Chang2, Alex MacKay1,3, and Carl A Michal1

1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2Department of Neurology, University of British Columbia, Vancouver, BC, Canada, 3UBC MRI Research Centre, Department of Radiology, University of British Columbia, Vancouver, BC, Canada

Inhomogeneous MT (IHMT) shows promise for myelin-selectivity. Images acquired with soft prepulses at positive and negative offsets simultaneously show a reduced intensity compared to images with a single positive or negative offset prepulse. The leading hypothesis is that this works due to inhomogeneous broadening of the lipid proton line. Our results contradict this. We show that IHMT can be explained by a simple spin-1 model of a coupled methylene pair, and that it occurs in homogeneously-broadened systems (hair and wood). We propose the relevant timescales for IHMT are the dipolar coupling correlation time and the prepulse nutation period.

306 11:48
In vivo quantitative Magnetisation Transfer in the cervical spinal cord using reduced Field-of-View imaging: a feasibility study
Marco Battiston1, Francesco Grussu1, James E. M. Fairney2,3, Ferran Prados1,4, Sebastien Ourselin4, Mara Cercignani5, Claudia Angela Michela Gandini Wheeler-Kingshott1,6, and Rebecca S Samson1

1NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom, 2UCL Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom, 3Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, United Kingdom, 4Translational Imaging Group, Centre for Medical Image Computing, UCL Department Medical Physics and Bioengineering, University College London, London, United Kingdom, 5CISC, Brighton & Sussex Medical School, Brighton, United Kingdom, 6Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy

Quantitative Magnetization Transfer (qMT) Imaging techniques offer the possibility to estimate tissue macromolecular fraction, which has been shown to be specific for myelin in the brain and spinal cord. To date, applications of qMT in the spinal cord have been hampered by prohibitive protocol duration. We propose a novel approach for qMT in the spinal cord based on the combination of off-resonance saturation and small field-of-view imaging, with the potential of reducing the scan time needed to perform qMT in the spinal cord.


Oral

fMRI: The Cutting Edge in Connectivity

Room 331-332 10:00 - 12:00 Moderators:Kai-Hsiang Chuang & Maria Fernandez-Seara

307 10:00
Cerebral Cortex Parcellation by Fusion of Local and Global Functional Connectivity Feature
Alexander Schaefer1, Ru Kong1, Evan M. Gordon2, Timothy Laumann 3, Simon B. Eickhoff4,5, Xi-Nian Zuo6, Avram J. Holmes7, and B.T. Thomas Yeo1

1Department of Electrical and Computer Engineering, ASTAR-NUS Clinical Imaging Research Centre, Singapore Institute for Neurotechnology and Memory Networks Program, National University of Singapore, Singapore, Singapore, 2VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX, United States, 3Department of Neurology, Washington University in St. Louis, St. Louis, MO, United States, 4Institut for Clinical Neuroscience, Heinrich Heine University, Düsseldorf, Germany, 5Institute for Neuroscience and Medicine, Research Center Jülich, Jülich, Germany, 6Lab for Functional Connectome and Development, Division of Cognitive and Developmental, Chinese Academy of Sciences, Beijing, China, People's Republic of, 7Department of Psychology, Yale University, New Haven, CT, United States

Current approaches to cerebral cortex parcellation with resting-state functional connectivity MRI (fcMRI) can be divided into local (e.g., fcMRI gradients) and global (e.g., clustering) approaches. Previous work suggests that local and global approaches capture complementary aspects of brain organization. Here we propose a novel hidden Markov Random Field model that fuses local connectivity gradients with global functional connectivity similarities. The resulting parcellation compares favorably with a state-of-the-art parcellation in terms of (1) parcel homogeneity in two different datasets and (2) agreement with cytoarchitectonic and visuotopic boundaries.

308 10:12
Track-weighted dynamic functional connectivity (TWdFC): a new method to study dynamic connectivity
Fernando Calamante1,2, Robert Elton Smith1, Xiaoyun Liang1, Andrew Zalesky3, and Alan Connelly1,2

1The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia, 2Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia, 3Melbourne Neuropsychiatry Centre and Melbourne School of Engineering, The University of Melbourne, Melbourne, Australia

There is great interest in the study of brain connectivity (structural and functional), and on the development of methods that facilitate these investigations. In functional connectivity (FC), there is also growing interest in characterising the dynamic changes (dynamic-FC, dFC). Track-weighted FC (TWFC) was proposed as a means to combine the structural and (static) functional information into a single image, by integrating a functional network with a diffusion MRI tractogram. Here we propose TW-dynamic-FC (TWdFC), by extending TWFC in two ways: first, it does not rely on an a-priori FC network; second, it allows studying dFC. 

309
10:24
Beat-to-beat blood pressure fluctuations are present in time-frequency dynamics of resting-state fMRI
Joseph R Whittaker1, Molly G Bright1,2, Ian D Driver1, and Kevin Murphy1

1CUBRIC, School of Psychology, Cardiff University, Cardiff, United Kingdom, 2Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom

A pilot study of fMRI time-frequency dynamics, characterized using a maximal overlap discrete wavelet transform, demonstrates matched frequency correlations with beat-to-beat mean arterial blood pressure fluctuations. Voxel-wise correlations between fMRI and blood pressure wavelet coefficients, on a frequency scale centred at 0.1Hz, reveal distributed and structured spatial variance across the brain. We demonstrate that functional connectivity methods that include time-frequency representations of fMRI data are likely very sensitive to these blood pressure fluctuations. 

310 10:36
­A cortical and sub-cortical parcellation clustering by intrinsic functional connectivity
Ying-Chia Lin1, Tommaso Gili2,3, Sotirios A. Tsaftaris 1,4, Andrea Gabrielli5, Mariangela Iorio3, Gianfranco Spalletta3, and Guido Caldarelli1

1IMT Institute for Advanced Studies Lucca, Lucca, Italy, 2Enrico Fermi Centre, Rome, Italy, 3IRCCS Fondazione Santa Lucia, Rome, Italy, 4Institute of Digital Communications, School of Engineering, The University of Edinburgh, Edinburgh, United Kingdom, 5ISC-CNR, UOS Sapienza, Dipartimento di Fisica, Universita Sapienza, Rome, Italy

Network analysis of resting-state fMRI (rsfMRI) has been widely utilized to investigate the functional architecture of the whole brain. Here we propose a robust parcellation method that first divides cortical and sub-cortical regions into sub-regions by clustering the rsfMRI data for each subject independently, and then merges those individual parcellations to obtain a global whole brain parcellation. To do so our method relies on majority voting (to merge parcellations of multiple subjects) and enforces spatial constraints within a hierarchical agglomerative clustering framework to define parcels that are spatially homogeneous.

311
10:48
Low Frequency Optogenetic Stimulation of Dentate Gyrus Enhances Brain Functional Connectivity Revealed by Resting-State fMRI
Russell W Chan1,2, Alex TL Leong1,2, Patrick P Gao1,2, Y S Chan3, W H Yung4, Kevin K Tsia2, and Ed X Wu1,2

1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, China, People's Republic of, 2Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China, People's Republic of, 3School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China, People's Republic of, 4School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China, People's Republic of

Low frequency coherent rsfMRI signals (<0.1Hz) do not match the bandwidth of established neuronal oscillations, highlighting a gap in our knowledge regarding the neuronal basis of rsfMRI underlying long-range brain networks. In this study, optogenetics and rsfMRI were combined to investigate the neuronal basis of rsfMRI connectivity by probing alternations of brain functional connectivity before, during and after low frequency stimulation in dorsal dentate gyrus. Our results demonstrated that low frequency optogenetic stimulation enhanced brain functional connectivity. This indicated that low frequency neuronal oscillations contribute and underlie the synchronized long-range rsfMRI brain functional networks.

312 11:00
Functional MRI reveals striatal–thalamic connectivity in cognitive neural behavior altered by central thalamic deep brain stimulation
Hsin-Yi Lai1, Hui-Ching Lin2,3, Yu-Chun Lo4, Lun-De Liao5,6, Wei-Che Wei7, and You-Yin Chen7

1Interdisciplinary Institute of Neuroscience and Technology (ZIINT), Zhejiang University, Hangzhou City, China, People's Republic of, 2Department and Institute of Physiology, National Yang-Ming University, Taipei, Taiwan, 3Brain Research Center, National Yang Ming University, Taipei, Taiwan, 4Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, 5Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli County, Taiwan, 6Singapore Institute for Neurotechnology, National University of Singapore, Singapore, Singapore, 7Department of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan

This study demonstrates neuronal striatal–thalamic connectivity modulated by direct stimulating the central thalamus in rats. Our results indicate that the CT-DBS modulate the neuronal activity in bilateral anterior cingulate cortex, caudate-putamen and somatosensory cortex and increases in functional connectivity between the striatum and parafascicular thalamic nucleus, hippocampus and primary motor cortex to shorten the cognitive related behavior task. CT-DBS fMRI has potential to explore functional connectivity in the brain and monitor functional plasticity changes in a specific neuroanatomical pathway in vivo.

313
11:12
The structural basis for supporting functional connectivity in mice
Joanes Grandjean1, Valerio Zerbi2, Nicole Wenderoth2, and Markus Rudin1

1University and ETH Zurich, Zurich, Switzerland, 2ETH Zurich, Zurich, Switzerland

Connectomics holds promise to foster our understanding of the healthy and disordered brain. MRI has been the method of choice for such analysis, combining diffusion weighted with functional imaging to resolve structural and functional connectivity, respectively.  However, both methods are indirect measures prone to bias and artifacts. In mice, structural connectivity has been reconstructed with high spatial resolution by mapping the distribution of viral tracers following local injections at multiple sites offering a unique opportunity to compare functional connectivity with detailed mono-synaptic projections. Such comparisons should help bridging functional and structural connectivity in rodents with implications for human studies.

314
11:24
Characterization of acute phencyclidine-induced dose-dependent schizophrenic symptoms in rat: relationship between functional connectivity, hemodynamic response, behavior, and neurotransmitter levels
Jaakko Paasonen1, Raimo A Salo1, Jouni Ihalainen2, Juuso Leikas2, Katja Savolainen2, Markus M Forsberg2, and Olli Gröhn1

1Department of Neurobiology, University of Eastern Finland, Kuopio, Finland, 2School of Pharmacy, University of Eastern Finland, Kuopio, Finland

Schizophrenia is a disorder that lack effective medication. In order to improve treatments, better disease models are required. Here, phencyclidine (PCP)-induced schizophrenic symptoms were investigated in rats with fMRI. Results were compared with microdialysis measurements and behavioral tests. At PCP doses ≥ 3 mg/kg, characteristics for psychotic symptoms were detected in functional connectivity (FC), having good correspondence with locomotor and dopamine activity. With PCP doses ≤ 2 mg/kg, markers for psychotic symptoms were absent. The FC of mesolimbic pathway was still affected, and social and cognitive deficits were confirmed in behavioral tests. Thus, PCP ≤ 2 mg/kg induces specifically the social and cognitive schizophrenic deficits.

315 11:36
ACC GABA levels predict activity and connectivity in the fronto-striatal network during interference inhibition in borderline personality disorder
Guoying Wang1, Julia van Eijk1, Traute Demirakca1, Markus Sack1, Sylvia Cackowski2, Annegret Krause-Utz2, Christian Schmahl2, and Gabriele Ende 1

1Neuroimaging, Central Institute of Mental Health, Mannheim, Germany, 2Psychosomatic Medicine and Psychotherapy, Central Institute of Mental Health, Mannheim, Germany

By combining the MRS and fMRI technique, we tested whether ACC GABA levels would predict the activity and connectivity in fronto-striatal networks during interference inhibition (Simon task) in BPD patients. BPD patients showed a significant positive correlation between ACC GABA levels and BOLD responses in fronto-striatal regions during interference inhibition. Additionally, ACC GABA levels in BPD patients were positively related to ACC-caudate functional connectivity during the incongruent condition. Our findings highlight that the GABAergic system in the ACC plays an important role in the modulation of impulsivity via regulating the local neural activity and remote connectivity between key regions.

316 11:48
Fluctuations in Functional Connectivity Predict Shifts in Arousal State
Chenhao Wang1, Ju Lynn Ong1, Amiya Patanaik1, Juan Zhou1,2, and Michael W. L. Chee1

1Neuroscience and Behavioral Disorders Program, Duke-NUS Graduate Medical School Singapore, Singapore, Singapore, 2Clinical Imaging Research Center, Agency for Science, Technology and Research, Singapore, Singapore

To elucidate relationship between fluctuation in functional connectivity and behavior we estimated dynamic connectivity states (DCS) from task-free fMRI obtained from sleep-deprived healthy young adults. Using spontaneous eye closures as a proxy for vigilance, we identified two DCS that were associated with high and low arousal respectively. DCS exhibiting similar connectivity patterns were also observed when individuals were performing an auditory vigilance task. Dwell time in high or low arousal DCS predicted task performance. Additionally, fluctuations in DCS and task response time were correlated. Fluctuations in functional connectivity appear to be related to spontaneous changes in arousal that affect vigilance.


Oral

Velocity & Flow Quantification

Room 334-336 10:00 - 12:00 Moderators:Jeremy Collins & Oliver Wieben

317
10:00
4D flow MRI-Derived Hemodynamic Atlases of the Left Ventricle with Hypertrophic Cardiomyopathy Demonstrate Abnormally Elevated Blood Flow Velocities
Pim van Ooij1, Alex J Barker2, Henk A Marquering3, Gustav J Strijkers3, James C Carr2, Michael Markl2,4, and Aart J Nederveen5

1Radiology, Academic Medical Center, Amsterdam, Netherlands, 2Radiology, Northwestern University, Chicago, IL, United States, 3Biomedical Engineering & Physics, Academic Medical Center, Amsterdam, Netherlands, 4Biomedical Engineering, Northwestern University, Chicago, IL, United States, 5Academic Medical Center, Amsterdam, Netherlands

Altered hemodynamics in the left ventricle (LV) may contribute to heart failure in hypertrophic cardiomyopathy (HCM). The aim of this was study was to employ 4D flow MRI to identify regions with altered velocity in HCM patients based on the concept of 'LV flow heat maps' comparing velocity fields in HCM patients with an atlas derived from healthy controls. In the ejection phase, abnormally elevated velocity was found in the LV outflow tract, whereas the filling phase showed elevated velocity in the LV apex.

318 10:12
Characterization of aortic blood flow after aortic valve replacement by 4D flow MRI
Alex S Hong1, Emilie Bollache1, Pim van Ooij1, James C Carr1, Alex J Barker1, Jeremy D Collins1, and Michael Markl2

1Department of Radiology, Northwestern University, Chicago, IL, United States, 2Department of Radiology, Department of Biomedical Engineering, Northwestern University, Chicago, IL, United States

Aortic valve replacement (AVR) is an effective surgical approach to treating aortic valvular disease, but it is unclear if and what type of prosthesis can fully reproduce physiologically normal flow characteristic of a native aortic valve. We utilized 4D flow MRI to systematically compare blood flow in the thoracic aorta in post-AVR (bioprosthetic vs. mechanical) patients and healthy controls. Both bioprosthetic and mechanical valves were found to produce higher peak systolic flow velocities and peak wall shear stress in the ascending aorta than native valves, demonstrating the presence of significant changes in aortic blood flow in AVR patients.

319 10:24
Pressure Gradient Measurement in the Coronary Artery Using Phase Contrast (PC)-MRI: Initial Patient Results Towards Noninvasive Quantification of Fractional Flow Reserve
Zixin Deng1,2, Sangeun Lee3, Zhaoyang Fan1, Christopher Nguyen1, Iksung Cho3, Qi Yang1, Xiaoming Bi4, Byoung-Wook Choi5, Jung-Sun Kim3, Daniel Berman1, Hyuk-Jae Chang3, and Debiao Li1

1Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States, 2Bioengineering, University of California, Los Angeles, Los Angeles, CA, United States, 3Cardiology, Severance Hospital, Yonsei Univeristy College of Medicine, Seoul, Korea, Republic of, 4R&D, Siemens Healthcare, Los Angeles, CA, United States, 5Radiology, Severance Hospital, Yonsei Univeristy College of Medicine, Seoul, Korea, Republic of

Fractional flow reserve is an invasive diagnostic tool to evaluate the functional significance of a coronary stenosis by quantifyin­g the pressure gradient (ΔP) across the stenosis. We proposed a non-invasive technique to derive ΔP using Phase-contrast (PC)-MRI in conjunction with the Navier-Stokes equations (ΔPMR). Excellent correlation was observed between derived ΔPMR and measure ΔP from a pressure transducer in a small caliber phantom model. A significant increase in ΔPMR was seen in the patient group vs. healthy controls. Preliminary results suggested that noninvasive quantification of ΔPMR in coronary arteries is feasible. 

320 10:36
Cine Phase Contrast Simultaneous Multi-Slice imaging of blood flow and CSF motion.
David A Feinberg1,2, Alexander Beckett1, An T Vu1,2, and Liyong Chen2

1Helen Wills Neuroscience Institute, University of California, Berkeley, CA, United States, 2Advanced MRI Technologies, Sebastopol, CA, United States

The purpose was to develop and evaluate a novel approach to MR phase imaging of blood flow and CSF flow by combining cine phase contrast (cine-PC) with simultaneous multi-slice (SMS) technique to measure velocity in several slice planes simultaneously. Comparisons were made between SMS 2-4 and conventional single-slice 2D cine-PC GE imaging. The velocity curves measured in internal carotid (ICA) and vertebral arteries and jugular veins and aqueductal CSF were similar between SMS and conventional single-slice cine-PC. In ICA correlations (R=0.92-0.98) in 6 subjects. This new ability for simultaneous cross-sectional hemodynamic quantification may be useful for medical diagnoses.  

321 10:48
Vortex-ring mixing as a measure of diastolic function of the human heart: phantom validation and initial observations in healthy volunteers and patients with heart failure
Johannes Töger1,2, Mikael Kanski1, Per M Arvidsson1, Marcus Carlsson1, Sándor J Kovács3, Rasmus Borgquist4, Johan Revstedt5, Gustaf Söderlind2, Håkan Arheden1, and Einar Heiberg1,2,6

1Department of Clinical Physiology, Lund University Hospital, Lund University, Lund, Sweden, 2Department of Numerical Analysis, Centre for Mathematical Sciences, Lund University, Lund, Sweden, 3Department of Internal Medicine, Washington University School of Medicine, St Louis, MO, United States, 4Department of Arrhythmias, Lund University Hospital, Lund University, Lund, Sweden, 5Department of Energy Sciences, Lund University, Faculty of Engineering, Lund, Sweden, 6Department of Biomedical Engineering, Lund University, Faculty of Engineering, Lund, Sweden

Diastolic dysfunction of the left ventricle (LV) of the heart is a severe condition associated with poor prognosis. However, objective and reproducible assessment of diastolic function remains a challenge. We propose a new method using 4D flow MR by quantification of blood mixing within the LV diastolic vortex-ring. Phantom validation showed fair agreement between 4D flow MR and planar laser-induced fluorescence (PLIF). Quantitative vortex-ring mixing differs between healthy controls and patients with heart failure, which demonstrates its potential as a marker of diastolic dysfunction.

322 11:00
Dynamic assessment of atrioventricular junction (AVJ) based on radial long-axis cine cardiac MR imaging
Shuang Leng1, Shuo Zhang2, Xiaodan Zhao1, Baoru Leong1, Yiying Han1, Yasutomo Katsumata3, Stuart Cook1,4, Ru San Tan1,4, and Liang Zhong1,4

1National Heart Centre Singapore, Singapore, Singapore, 2Philips Healthcare Singapore, Singapore, Singapore, 3Philips Healthcare Japan, Tokyo, Japan, 4Duke-NUS Graduate Medical School Singapore, Singapore, Singapore

We have developed a semi-automatic tracking system of atrioventricular junction (AVJ) deformation with two-, three-, and four-chamber cardiovascular magnetic resonance (CMR) long-axis images 1. In this study, we applied the feature-tracking technique in 18 radial rotational long-axis cine CMR planes and evaluated the motion of 36 evenly located AVJ points. Results have shown that 1) the obtained average AVJ velocities (Sm, Em and Am) and maximal displacements are independent of the number of AVJ points selected, and 2) the routinely acquired CMR imaging generated in clinical practice are sufficient enough for dynamic assessment of AVJ deformation.

323 11:12
3D Blood Flow Velocity Distribution in the Normal Aorta: Effect of Age and Gender Across 101 Subjects
Julio Garcia1, Roel L.F. van der Palen2, Alex J. Barker1, Jeremy D. Collins1, James C. Carr1, Joshua Robinson3, Cynthia Rigsby3, and Michael Markl1,4

1Radiology, Northwestern University, Chicago, IL, United States, 2Pediatric Cardiology, Leiden University Medical Center, Leiden, Netherlands, 3Department of Medical Imaging, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, United States, 4Biomedical Engineering, Northwestern University, Evanston, IL, United States

The systematic characterization of effects in aortic disease patients and healthy controls is important to improve disease diagnosis. 4D flow MRI can be applied for the analysis of altered hemodynamics in cardiovascular disease. However, data analysis can be time consuming and often data are not fully utilized by analysis based on 2D planes. This study aimed to systematically apply flow distribution analysis in the entire volume of the aorta to establish normative reference values across a wide age range from pediatric to adult subjects.

324
11:24
High Quality Preclinical 4D-Flow Phase Contrast Imaging
Moritz Braig1, Jochen Leupold1, Ko Cheng-Wen2, Marius Menza1, Juergen Hennig1, Jan Korvink3, and Dominik von Elverfeldt1

1University Medical Center Freiburg, Freiburg, Germany, 2Dept. Computer Science and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan, 3Institute of Microstructure Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany

So far preclinical 4D-Flow MRI has not been able to deliver an analysis of complex flow due to low resolution. The presented framework and improvements allow high quality data acquisitions with a reduced measurement time and the possibility to visualize regional flow abnormalities. An automatic magnitude segmentation in every timeframe combines anatomic information with the underlying blood flow showing even small vessels. It will draw new conclusions in mouse models of cardiovascular diseases as a valuable tool for preclinical researchers.

325 11:36
Ultra-High-Dimensional Flow Imaging (N-D Flow)
Joseph Y. Cheng1, Tao Zhang1, Marcus T. Alley1, Michael Lustig2, John M. Pauly3, and Shreyas S. Vasanawala1

1Radiology, Stanford University, Stanford, CA, United States, 2Electrical Engineering & Computer Sciences, University of California, Berkeley, CA, United States, 3Electrical Engineering, Stanford University, Stanford, CA, United States

Volumetric cardiac-resolved flow imaging (4D flow) can enable the assessment of flow, function, and anatomy from a single sequence. Here, 4D flow is extended to higher dimensional space as N-D flow. By resolving different dynamics such as respiration or contrast enhancement, more diagnostic information can be extracted for a single-sequence protocol. Furthermore, this potentially improves image quality and quantification accuracy. N-D flow is enabled by a compressed-sensing and parallel imaging based acquisition and reconstruction. The feasibility of this approach is demonstrated for pediatric imaging. 

326 11:48
In vitro validation of Cartesian 4D flow mapping using patient-specific 3D printed total cavo-pulmonary connection models
Zachary Borden1, Peng Lai2, Ann Shimakawa2, Alejandro Roldan-Alzate1,3, and Christopher J Francois1

1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2GE Healthcare, Menlo Park, CA, United States, 3Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, United States

Congenital heart disease is a common disease process which benefits from MRI 4D flow analysis. In a total cavo-pulmonary connection model, Cartesion 4D Flow mapping using k-t acceleration and variable density signal averaging correlates well with US flow probe data and 2D PC measurements. The improved post processing efficiency of Cartesian acquisition may allow more widespread adoption of 4D flow technology for analyzing congenital heart disease.


Oral

Normal Brain: Measurement & Characterisation

Hall 606 10:00 - 12:00 Moderators:Jalal Andre & Christopher G Filippi

327 10:00
UK Biobank: Brain imaging protocols and first data release
Karla L Miller1, Neal K Bangerter2, Fidel Alfaro Almagro1, David L Thomas3, Essa Yacoub4, Junqian Xu5, Andreas J Bartsch1,6, Saad Jbabdi1, Stamatios N Sotiropoulos1, Mark Jenkinson1, Jesper Andersson1, Ludovica Griffanti1, Peter Weale7, Iulius Dragonu7, Steve Garratt8, Sarah Hudson8, Rory Collins8,9, Paul M Matthews10, and Stephen M Smith1

1FMRIB Centre, University of Oxford, Oxford, United Kingdom, 2Electrical and Computer Engineering, Brigham Young University, Provo, UT, United States, 3Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, University College London, London, United Kingdom, 4Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 5Icahn School of Medicine at Mount Sinai, New York, NY, United States, 6Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany, 7Siemens Healthcare (UK), London, United Kingdom, 8UK Biobank Ltd, Stockport, United Kingdom, 9Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom, 10Department of Medicine, Imperial College London, London, United Kingdom

UK Biobank is a prospective epidemiological study of 500,000 participants consisting of extensive questionnaires, physical measures and biological samples, linking to long-term health outcomes. The imaging extension for the UK Biobank ultimately aims to image 100,000 subjects from this cohort, including brain, cardiac and body MRI, bone scans and carotid ultrasound. We overview the brain imaging component, which includes structural, functional and diffusion MRI. The value of this open resource arises not only from multi-modal/multi-organ imaging, but also from the depth of other demographic, phenotypic and exposure data, and will increase over time as clinical outcomes are realized in the population.

328
10:12
On the Relationship between Cellular and Hemodynamic Properties of the Human Brain Cortex over Adult Lifespan
Yue Zhao1, Jie Wen2, Anne Cross3, and Dmitriy Yablonskiy2

1Chemistry, Washington University in St. Louis, St. Louis, MO, United States, 2Radiology, Washington University in St. Louis, St. Louis, MO, United States, 3Neurology, Washington University in St. Louis, St. Louis, MO, United States

Establishing baseline MRI biomarkers for normal brain aging is significant and valuable. In this study, we use previously developed approach to measure tissue-specific transverse relaxation rate constant (R2*t) and BOLD contributions to GRE signal, thus providing information on tissue cellular and hemodynamic properties. The VSF approach is applied for background gradient correction together with navigator echo to minimize artifacts from physiological fluctuations. Our results show age-related R2*t increases in most cortical regions and age-independent behavior of most hemodynamic parameters. We hypothesize that R2*t could serve as a biomarker of the cortical “cellular packing density”, which mostly reflects the neuronal density.

329
10:24
Venous metrics in a large cohort of healthy elderly individuals from susceptibility-weighted images and quantitative susceptibility maps
Phillip G. D. Ward1,2, Parnesh Raniga1, Nicholas J. Ferris1,3, David G. Barnes2,4, David L. Dowe2, Elsdon Storey5, Robyn L. Woods6, and Gary F. Egan1,7

1Monash Biomedical Imaging, Monash University, Clayton, Australia, 2Faculty of Information Technology, Monash University, Clayton, Australia, 3Monash Imaging, Monash Health, Clayton, Australia, 4Monash eResearch Centre, Monash University, Clayton, Australia, 5Department of Neurology, Monash University, Clayton, Australia, 6Department of Epidemiology & Preventative Medicine, Monash University, Melbourne, Australia, 7ARC Centre of Excellence for Integrative Brain Function, Melbourne, Australia

In this study we examine venous characteristics of elderly individuals in a large healthy population. Venograms were generated from susceptibility-weighted images and quantitative susceptibility maps using state-of-the-art automated venography. Venous density and oxygen extraction fraction were calculated in different brain regions. The pattern of metabolic demand (oxygen extraction fraction) is found to be consistent with rest and passive observation. Additionally, our results suggest that venous density may be a potential biomarker.

330 10:36
In Vivo Characterization of Brain Ultrashort-T2 Components
Tanguy Boucneau1,2, Shuyu Tang1,3, Misung Han1, Roland G Henry1,4, Duan Xu1,3, and Peder Eric Zufall Larson1,3

1Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, CA, United States, 2Physics, Ecole Normale Supérieure de Cachan, Cachan, France, 3UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, San Francisco, CA, United States, 4Neurology, University of California - San Francisco, San Francisco, CA, United States

It has recently been shown that myelin contains ultrashort T2 components with sub-millisecond relaxation times that are not observed with conventional pulse sequences and maybe associated with bound protons in the myelin phospholipid membranes.We performed ultrashort T2* relaxometry in vivo to characterize these components with a 3D ultrashort echo time (UTE) pulse sequence at 7T.We observed an ultrashort T2 component (T2* $$$\approx 100 \mu s$$$) as well as a short T2 component (T2* $$$\approx 1.5 ms$$$) that had a distinct frequency shift corresponding to the methylene proton chemical shift, which to our knowledge has never been observed in vivo.These components were validated in an ex vivo post-mortem brain specimen, and may provide valuable new biomarkers of myelin density, structure, and integrity.

331 10:48
Multi-parameter mapping, fat/water separation and functional imaging with a two-sequence brain morphometry protocol
Andre Jan Willem van der Kouwe1, Fikret Isik Karahanoglu1, Matthew Dylan Tisdall1, Paul Wighton1, Himanshu Bhat2, Thomas Benner3, and Jonathan R Polimeni1

1Athinoula A. Martinos Center, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 2Siemens Healthcare, Charlestown, MA, United States, 3Siemens Healthcare, Erlangen, Germany

We present an efficient two-sequence protocol for quantifying multiple parameters in a 1 mm isotropic brain morphometry examination. The protocol comprises a multiple gradient echo (TE), multiple inversion (TI) time MPRAGE (MEMPxRAGE) and a two-flip-angle balanced SSFP (TrueFISP) sequence. Proton density and T1 maps are estimated from the MEMPxRAGE data using the multi-TI data and a Bloch simulation. With the T1 map and TrueFISP data, the T2 map is estimated using DESPOT2. Fat, water and B0 maps are obtained from the multi-TE data using the IDEAL algorithm.  The MEMPxRAGE scan includes embedded 3D EPI-based navigators encoding low resolution functional information.

332 11:00
Reproducibility of fast three-dimensional macromolecular proton fraction mapping of the human brain: global tissue characterization and volume measurements
Vasily L. Yarnykh1,2

1Radiology, University of Washington, Seattle, WA, United States, 2Research Institute of Biology and Biophysics, Tomsk State University, Tomsk, Russian Federation

A new method for fast high-resolution whole-brain three-dimensional (3D) mapping of the macromolecular proton fraction (MPF) based on three source images has been recently proposed. In this study, reproducibility of repeated MPF measurements in white and gray matter with simultaneous estimation of tissue volumes using automated segmentation of 3D MPF maps obtained with isotropic resolution of 1.25 mm was assessed. MPF measurements in brain tissues are highly reproducible with coefficients of variation <1.5%. 3D MPF mapping provides “all-in-one” solution for simultaneous characterization of myelination and volumetric changes in brain tissues.

333 11:12
Automated Measurements of Brain Morphometry Derived from T1-weighted Magnetic Resonance Imaging Fluctuate from Morning to Afternoon
Aaron Trefler1, Neda Sadeghi2, Adam Thomas1, Carlo Pierpaoli2, Chris Baker1, and Cibu Thomas3

1National Institute of Mental Health, Bethesda, MD, United States, 2National Institute of Child Health and Human Development, Bethesda, MD, United States, 3Center for Neuroscience and Regenerative Medicine, Bethesda, MD, United States

Automated measures of brain morphometry derived from T1-weighted (T1W) images are typically used as proxy measures to investigate the relation between brain structure and behavior. However, the computation of T1W morphometric measures can be influenced by subject-related factors such as head motion1 and level of hydration2. Here, we provide a comprehensive assessment of the impact of time-of-day (TOD) on widely used measures of brain morphometry in healthy young adults. Our results show that the apparent volume of all major tissue compartments as well as measures of brain morphometry such as cortical thickness and gray matter density are significantly influenced by TOD. 

334
11:24
Optimized Inversion-Time Schedules For High-Resolution Multi-Inversion EPI Quantitative Measurements of T1
Ouri Cohen1,2, Ville Renvall3, and Jonathan Polimeni1,2

1Athinoula A. Martinos Center, Charlestown, MA, United States, 2Radiology, Massachusetts General Hospital, Boston, MA, United States, 3Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, Finland

A novel optimized method for high-resolution quantitative EPI measurements of T1 is introduced and validated on a 3T clinical scanner in a phantom and a healthy volunteer. The method offers a 5-fold acceleration in scan time over previous techniques allowing fully quantitative 1.2 mm3 isotropic T1 maps in less than 30 seconds. 

335 11:36
Cerebral gray matter volume changes caused by exposure to hypobaric environment: a preliminary study
Dandan Zheng1, Wenjia Liu2, Li Zheng3, and Lin Ma2

1MR Research China, GE Healthcare, Beijing, China, People's Republic of, 2Radiology Department, Beijing Military General Hospital, Beijing, China, People's Republic of, 3Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, China, People's Republic of

Acute mountain sickness is a series of pathologic reactions during rapid exposing to low pressure hypoxic high altitude environment, which is a widespread illness among un-acclimatized individuals in plateau. Human always stay in plain will display some common physiological and pathological changes of brain, such as change of cerebral blood flow, cerebral pressure and brain volume. The aim of the present study was to investigate whether there was different change of gray matter volume in some brain regions related to AMS development before, during and after exposing to the real high altitude environment.

336 11:48
Regional Brain Motion Varies with Subject Positioning: A Study Using Displacement Encoding with Stimulated Echoes (DENSE)
Xiaodong Zhong1, Zihan Ye2, Tucker Lancaster3, Deqiang Qiu3, Brian M. Dale4, Amit Saindane3, and John N. Oshinski2,3

1MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States, 2Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States, 3Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States, 4MR R&D Collaborations, Siemens Healthcare, Cary, NC, United States

Displacement encoding with stimulated echoes (DENSE) with high motion sensitivity was used to investigate the influence of subject position (prone versus supine) on regional brain motion. Preliminary results in 9 volunteers demonstrated that there is a significant difference in displacement with a change in position. Displacements were significantly increased in the frontal lobe going from the prone to the supine position and significantly increased in the occipital lobe going from the supine to the prone position.


Oral

Brain Motion Correction

Summit 1 10:00 - 12:00 Moderators:Rita Nunes & Oliver Speck

337
10:00
Advances in Prospective Motion Correction with Gradient Tones
Maximilian Haeberlin1, Alexander Aranovitch1, Bertram Wilm1, David Otto Brunner1, Benjamin Dietrich1, Barmet Christoph2, and Klaas Paul Pruessmann1

1Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland, 2Skope Magnetic Resonance Technologies, Zurich, Switzerland

A system for prospective motion correction using field probes and gradient tones is presented that is independent of sequence parameters and thus compatible with clinically relevant scans. An examples of a successfully corrected MPRAGE sequence is shown and the bandwidth and the amount of unintentional head motion is measured during a 32 min. scan.

338 10:12
High frequency orientation estimates for fast real-time motion correction using vector observations of gravity and the static magnetic field (B0).
Adam M.J. van Niekerk1, Paul Wighton2,3, Ali Alhamud1, Matthew D. Tisdall2,3, Andre J.W. van der Kouwe2,3, and Ernesta M. Meintjes1

1Human Biology, MRC/UCT Medical Imaging Research Unit, University of Cape Town, Cape Town, South Africa, 2Athinoula A. Martinos Center, Massachusetts General Hospital, Boston, MA, United States, 3Radiology, Harvard Medical School, Boston, MA, United States

In this study we propose a novel approach to motion correction in MRI that separates the challenges of tracking orientation and translation. We developed an external hardware device capable of high frequency orientation estimates independent of the pulse sequence. The device takes vector observations of gravity and the MRI scanner’s static magnetic field (B0) and is therefore free from many constraints of some existing external motion tracking techniques. Most notably, no scanner specific calibration is required and the device can be miniaturised. Translation estimates are achieved through the use of 3 high-speed orthogonal navigators. Line by line rigid body motion correction is implemented in a spoiled gradient echo pulse sequence. 

339 10:24
Prospective Motion Correction Using External Tracking and Intrinsic Motion Information
Michael Herbst1,2, Aditya Singh1, Benjamin Knowles2, Maxim Zaitsev2, and Thomas Ernst1

1JABSOM, University of Hawaii, Honolulu, HI, United States, 2Medical Physics, University Medical Center Freiburg, Freiburg, Germany

Prospective motion correction with external tracking was applied to high resolution diffusion weighted imaging, using a phase-segmented EPI readout strategy. To detect and correct for residual errors during prospective motion correction, real-time volumetric registration provides continuous feedback to the acquisition.

340 10:36
A Comparison of 19F NMR Field Probes and an Optical Camera System for Motion Tracking
Martin Eschelbach1, Alexander Loktyushin1, Paul Chang1,2, Jonas Handwerker3, Jens Anders3, Anke Henning1,4, Axel Thielscher1,5,6, and Klaus Scheffler1,7

1High Field MR Center, Max Planck Institute for biol. Cybernetics, Tuebingen, Germany, 2IMPRS for Cognitive and Systems Neuroscience University of Tuebingen, Tuebingen, Germany, 3Institute of Microelectronics, University of Ulm, Ulm, Germany, 4Institute for Biomedical Engineering, ETH Zürich, Zurich, Switzerland, 5Univ Copenhagen, Hvidovre Hosp, Danish Res Ctr Magnet Resonance, Hvidovre, Denmark, 6Tech Univ Denmark, Biomed Engn Sect, Lyngby, Denmark, 7Department of Biomedical Magnetic Resonance, University Tuebingen, Tuebingen, Germany

The goal of this study is to evaluate and compare motion tracking with two different modalities: NMR field probes and an optical MPT (Moiré Phase Tracking) camera system. This was done by simultaneously measuring the manually induced motion of a spherical phantom with both systems. Our experimental results indicate that the motion patterns measured with both methods are in good agreement. However, the accuracy of the motion estimates from the field probe measurements are of an order of magnitude worse than the camera's tracking results.

341 10:48
Fast calculation of phase accumulation due to pulsed gradients for arbitrary rigid body motion
Patrick Hucker1, Michael Dacko1, Michael Herbst2, Ben Knowles1, and Maxim Zaitsev1

1Dept. of Radiology · Medical Physics, University Medical Center Freiburg, Freiburg, Germany, 2John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States

A compact solution for phase calculation due to arbitrary rigid body motion based on  screw theory is presented. The proposed approach allows for rapid and quantitatively accurate calculations of the phase induced by the switching magnetic field gradients using motion tracking information e.g. from a motion tracking camera. The ability of predicting phase accumulation due to motion in presence of gradients is instrumental for achieving better correction of the motion-induced data inconsistencies for MR pulse sequences with extended signal preparation or readout periods.

342 11:00
Motion Detection and Correction for Carotid Artery Wall Imaging using Structured Light
Jin Liu1, Huijun Chen2, Jinnan Wang1, Niranjan Balu1, Haining Liu1, and Chun Yuan1

1University of Washington, Seattle, WA, United States, 2Tsinghua University, Beijing, China, People's Republic of

Carotid artery wall MRI is often affected by complex neck motion. We aimed to separate different motion components and correct them for better carotid artery wall delineation using structured light system. A healthy volunteer was scanned for 2D carotid MRI. It was demonstrated that voluntary abrupt motion, unconscious bulk motion and involuntary respiration can all be detected effectively. Both abrupt motion and bulk neck shift can be corrected for better vessel wall delineation, but the duration of abrupt motion can affect motion correction effectiveness. Bulk neck shift distance optimization by maximizing sharpness can future reduce motion artifact. 

343 11:12
Motion-corrected K-space Reconstruction for High Resolution Multi-shot Diffusion Imaging
Fuyixue Wang1, Zijing Dong1, Xiaodong Ma1, Erpeng Dai1, Zhe Zhang1, and Hua Guo1

1Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, People's Republic of

Recently, several techniques have been developed to be capable of correcting shot-to-shot phase variations of multi-shot acquisition in order to obtain diffusion images with high spatial resolution. However, longer acquisition time of multi-shot EPI makes these methods more sensitive to bulk motion. In this work, we developed a novel k-space based motion corrected reconstruction method for 2D navigated multi-shot DWI. Motion simulations and in-vivo head motion experiments validated the effectiveness of the proposed method, which can remove the ghosting artifacts from minuscule motion and the blurring from bulk motion.

344
11:24
Robust MR eye scanning: blink detection and correction using field probes
Joep Wezel1, Anders Garpebring2, Andrew G. Webb1, Matthias J. van Osch1, and Jan-Willem M. Beenakker3

1Radiology, Leiden University Medical Center, Leiden, Netherlands, 2Radiation Sciences, Umeå University, Umeå, Sweden, 3Ophthalmology, Leiden University Medical Center, Leiden, Netherlands

Eye-blinks result in significant artifacts in ocular MRI scans, often masking important clinical pathologies, such as small ocular tumors. The aim of this study is to detect and correct for these eye-blinks. We use a fluorine-based field probe to detect these eye-blinks via changes in the local magnetic field. The field probe measurements are linked to the MR-scanner which subsequently automatically reacquires the motion-corrupted part of k-space. This method effectively corrects for the main origin of image artifacts in ocular MRI, and thereby significantly improves the image quality in a clinical setting.

345
11:36
Head motion tracking and correction using discrete off-resonance markers (trackDOTS) for high-resolution anatomical imaging at 7T
João Jorge1, Daniel Gallichan2, and José P Marques3

1Laboratory for Functional and Metabolic Imaging, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 2Biomedical Imaging Research Center, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 3Donders Institute, Radboud University, Nijmegen, Netherlands

High-resolution imaging can be significantly affected by subject head motion. Here, we demonstrate the use of discrete off-resonance MR markers (“trackDOTS”) in head motion tracking and correction, for high-resolution anatomical imaging. This approach relies on fast 1D-projection acquisitions (under 50ms per measurement) which do not disturb the water signal. These measurements were incorporated in an MP2RAGE sequence, and a 0.6mm isotropic resolution image was acquired from a healthy subject. Motion timecourses estimated from the trackDOTS positions matched concomitant estimations performed with FatNavs (with deviations of 0.09±0.08mm for translations and 0.20°±0.19° for rotations); MP2RAGE image quality was visibly improved upon correction.

346 11:48