Evaluating MRE-Tract Integrity in HIV-CSVD Cohort: A Comprehensive Analysis with Functionally Defined Atlases and Neurocognitive Assessment

Motivation: MR-Elastography and diffusion-MRI represents complementary modalities with mechanical-and-structural information of the brain. Structural-connectomes alone lack tract-integrity information. Tissue viscoelastic-measures can provide valuable insights for tract-integrity when combined with connectomes. Goal(s): To aid the studies with neurodegeneration(HIV/CSVD), an analytical approach to combine viscoelastic-measures with diffusion-tractography is proposed which shows promise in targeted-analysis of functionally-defined-networks. Approach: For 14 functionally-defined brain-networks, viscoelastic measures from MRE are mean-sampled with the dMRI derived tracts. Then, the significantly-affected viscoelastic alterations are studied in-accord with cognitive-changes. Results: In a cohort of HIV-CSVD, by MRE-Tract-Integrity analysis, we reported significantly affected network connectivity that follows the cognitive decline(p<0.05) in processing-speed and motor-skills. Impact: The MRE-Tract-Integrity analysis enables us to study the missing mechanical properties of the structural connections from diffusion-tractography. This will help researchers performing targeted cognitive performance analysis with brain connectivity aided with mechanical basis which is a prominent marker for neural-change.