Abstract #2236

Automatic Measurement of Atrophy Rates in Hippocampal Subfields from Longitudinal High-Resolution T2-Weighted MRI

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.