DTI and DKI with Free Water Elimination Reveal Compounded Microstructural brain abnormalities in People with HIV with Chronic Marijuana Use

Motivation: Microstructural brain abnormalities are well documented in people with HIV (PWH). However, the effects of long-term marijuana use on white matter integrity are less established. Goal(s): The goal of this study is to examine if HIV infection and chronic marijuana use have differential or additive effect on white matter abnormalities. Approach: We use DTI/DKI with Free water elimination to evaluate diffusivity metrics at regions of interest in the whole-brain. Results: Our findings show that white matter injury is more severe in people with HIV with chronic marijuana use compared to HIV or marijuana alone. Impact: This study demonstrates the additive effect of HIV infection and chronic marijuana use on white matter microstructural integrity using multi-shell DTI and DKI with Free-water elimination.