Effect of repetitive head trauma on diffusion MRI derived measures of diffusivity and free water

In this study, we utilized the diffusion MRI (dMRI) data of cognitively impaired and nonimpaired active professional fighters from the Professional Fighters Brain Health Study and studied the effect of repeated head trauma on conventional and advanced dMRI derived measures of diffusivity and free-water fraction (fiso). Our study revealed increased f­iso and weighted FA in cognitively impaired active fighters, in addition to increased conventional radial and mean diffusivity, which was further associated with years of fighting in impaired fighters. Our study opens new avenues to explore advanced dMRI measures to understand the effect of repetitive head trauma on cognition.