Sandhitsu Das1, Brian Avants1,
John Pluta1, Caryne Craige1, Michael Weiner2,
Susanne Mueller2, Paul Yushkevich1
1PICSL, Department of
Radiology, University of Pennsylvania, Philadelphia, PA, United States; 2VA
Medical Center, University of California at San Francisco, San Francisco, CA,
United States
We present the first attempt at measuring longitudinal atrophy rates within the subfields of the hippocampal formation from focal in vivo T2-weighted MRI (HF-MRI). Commonly used T1-weighted structural MRI does not have sufficient intensity contrast to distinguish subfields. In HF-MRI, on the other hand, subfields are distinguishable, but the image is highly anisotropic with high in-plane resolution in slices oriented perpendicular to the long axis of the hippocampus and thick slices -- this poses certain methodological challenges in processing HF-MRI data. We carefully adapt existing techniques to address these challenges and show that significant effects can be measured in a cohort of cognitively impaired patients in subfields such as CA1.