Tensor-valued diffusion MRI detects brain microstructure changes in HIV infected individuals with cognitive...

Area of Science:

• Neuroimaging
• Neuroscience
• Infectious Diseases

Background:

• HIV-associated neurocognitive impairment affects up to 40% of people with HIV (PWH).
• Combination antiretroviral therapy (cART) may not fully reverse pre-existing brain injury.
• Subtle microstructural brain changes may persist despite cART.

Purpose of the Study:

• To assess the sensitivity of tensor-valued diffusion encoding for detecting microstructural brain changes in cART-treated PWH.
• To explore associations between diffusion metrics, neurocognitive scores, and biomarkers (NFL, GFAP).

Main Methods:

• 3T MRI with tensor-valued diffusion encoding was used for 24 PWH and 31 healthy controls.
• Cross-sectional study design.
• Analysis of white matter regions, neurocognitive performance, and plasma NFL/GFAP levels.

Main Results:

• Significant variations in b-tensor encoding metrics were found across white matter.
• Associations were observed between diffusion metrics, cognitive performance, and NFL/GFAP levels.
• A significant interaction between HIV status and imaging metrics impacted cognitive scores.

Conclusions:

• Tensor-valued diffusion encoding shows high sensitivity for detecting axonal injury in HIV infection.
• These metrics may be clinically relevant for understanding neurocognitive impairment in PWH.
• Further research can explore the clinical utility of these advanced neuroimaging techniques.