The following is a summary of “Structural and functional correlates of disability, motor and cognitive performances in multiple sclerosis: Focus on the globus pallidus,” published in the March 2024 issue of Neurology by Romanò et al.
Researchers started a retrospective study to examine alterations in the structure and function of the globus pallidus external (GPe) and internal (GPi) in people with multiple sclerosis (pwMS) compared to HCs and to analyze how these alterations relate to clinical disability, motor, and cognitive impairments.
They conducted MRI scans, including conventional, diffusion tensor MRI, and resting state (RS) functional MRI, on 60 pwMS and 30 HC matched for age and sex. Expanded Disability Status Scale (EDSS) scores were evaluated and administered through the timed 25-foot walk (T25FW) test, nine-hole peg test (9HPT), and paced auditory serial addition test (PASAT). Two operators segmented the GP into its components, GPe and GPi, and assessed volumes, T1/T2 ratio, diffusivity indices, and seed-based RS functional connectivity (FC).
The results showed that PwMS exhibited no atrophy or altered diffusivity measures of the GP. PwMS had a higher T1/T2 ratio in both GP regions than HC, which correlated with EDSS scores (ranging from 0.26 to 0.39, P-values between 0.01 and 0.05). RS FC analysis revealed component-specific functional alterations in PwMS: decreased RS FC between the GPe and frontoparietal cortices, decreased intra-GP RS FC, and increased RS FC between the GPi and the thalamus. Worse EDSS, 9HPT, T25FW, and PASAT scores were associated with modifications in GP RS FC (with correlation coefficients ranging from -0.51 to 0.51, and P-values below 0.001).
Investigators found no significant structural changes in the GP patients with MS, but abnormal iron levels and altered brain connectivity correlated with disability and cognitive issues.
Source: msard-journal.com/article/S2211-0348(24)00155-X/abstract#%20