# Portable Low‐Field Magnetic Resonance Imaging in People With Human Immunodeficiency Virus

## TL;DR

A portable low-field MRI system was tested for monitoring brain changes in people with HIV, showing potential for detecting atrophy in specific brain regions.

## Contribution

The study demonstrates the feasibility of using low-field MRI and machine learning to detect brain atrophy in people with HIV.

## Key findings

- PWH showed reduced caudate and putamen volumes compared to age-matched controls.
- LF-MRI and ML segmentation can detect brain atrophy in an outpatient setting.
- No significant differences in white matter hyperintensities were found between groups.

## Abstract

The aging population of people with HIV (PWH) raises heightened concerns regarding accelerated aging and dementia. Portable, low‐field MRI (LF‐MRI) is an innovative technology that could enhance access and facilitate routine monitoring of PWH. We sought to evaluate the feasibility of LF‐MRI and apply a machine learning (ML) segmentation algorithm to examine atrophy and white matter hyperintensities (WMH) in PWH compared to people without HIV (PWoH) of similar age.

Individuals with a confirmed diagnosis of HIV on antiretroviral therapy underwent LF‐MRI (64 mT) acquisition in the outpatient neurology clinic. PWoH with > 1 vascular comorbidity (VC cohort, n = 25) or with mild cognitive impairment (MCI cohort, n = 24) due to Alzheimer's disease served as comparators. LF‐MRI brain region segmentations were derived using the ML algorithm WMH‐SynthSeg in FreeSurfer. Brain regions corrected for intracranial volume were compared between cohorts after adjusting for age and sex.

Thirty virally suppressed PWH were included. LF‐MRI derived brain volumes from PWH demonstrated a reduction in volume of the caudate relative to PWoH with VC (p < 0.05). Volume of the putamen and white matter was reduced in PWH compared to VC (p < 0.05). Hippocampal volume was comparable between PWH and PWoH (p ≥ 0.05), while volume of the amygdala was reduced in those with MCI alone (p < 0.05). No differences in WMH were seen between these cohorts (p > 0.05).

LF‐MRI is feasible in an outpatient setting, and ML algorithms enable detection of regional atrophy and WMH in PWH. LF‐MRI may enable more frequent monitoring and earlier detection of atrophy in at‐risk populations.