P658. Longitudinal Evaluation of Hippocampal Volume in Recent Trauma Survivors

Reduced volume of the hippocampus (HC) has been repeatedly documented in Post-traumatic Stress Disorder (PTSD) patients, in whom it can represent either pre-traumatic vulnerability trait or post-exposure decay. Longitudinal brain volumetric studies of long-enough duration, proper timing, and reasonable attrition can inform that question. Here, we aimed to examine whether HC volume early after trauma is associated with the development of chronic PTSD, and whether there are time-dependent changes in HC volume during the first 14-months post-trauma.