Evolution of Microstructural Changes in a Mouse Model of Mild Traumatic Brain Injury

Single mild concussive impacts remain sparsely explored by in vivo neuroimaging techniques. Multimodal microstructural MRI has shown increased sensitivity and specificity to microstructural changes in various disease and injury models. In this work, we apply oscillating gradient spin-echo (OGSE) diffusion MRI, microscopic anisotropy (µA) diffusion MRI, and magnetization transfer (MT) MRI longitudinally to increase sensitivity to smaller spatial scales, disentangle fiber orientation dispersion from true microstructural changes, and acquire myelin sensitivity, respectively. We demonstrate that multimodal microstructural MRI provides sensitivity to evolving changes following a mild impact in both acute and chronic regimes, with OGSE demonstrating higher sensitivity than µA.