To assess epilepsy risk in a cohort of patients with post-traumatic contusions identified on MRI two-weeks post-injury using functional MRI to map the remote network effects of lesions.
Traumatic brain injury (TBI) is one of the leading causes of acquired epilepsy. Neuroimaging acquired after neurotrauma and prior to the onset of seizures may be used to develop predictive models of epilepsy risk. Prior studies offer mixed results on post-traumatic lesion localization and epilepsy risk; however, no study has evaluated the effect of post-traumatic lesions on remote neural networks on post-traumatic epilepsy risk.
We performed manual lesion (contusion) segmentation on two-week post-injury MRI of participants enrolled in phase one of the Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) study. Lesion core and edema were segmented using coregistered T1 and FLAIR contrasts. Each participant’s T1 image and lesion masks were then normalized to standard space where the lesion will be used as a seed in a seed-based connectivity analysis. For this analysis, we will use normative functional connectomes from the Human Connectome Project and compare lesion network maps of participants who later develop seizures to those with TBI who do not develop seizures. Group analysis will be carried out using the generalized linear model and threshold free cluster enhancement as implemented in FSL.
Of 606 TBI participants enrolled in phase one of TRACK-TBI, we identified 100 with at least one contusion identified on two-week post-injury MRI. Average core lesion volume was 2.2 mL and average edema volume was 128 mLs. Further results of the connectivity analyses are forthcoming.