Functional homotopic changes in multiple sclerosis with resting-state functional MR imaging.

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• The Corpus Callosum (CC) is implicated in Multiple Sclerosis (MS) pathogenesis, often presenting with interhemispheric dysfunction.
• Understanding alterations in interhemispheric functional connectivity is crucial for MS diagnosis and management.

Purpose of the Study:

• To investigate alterations in interhemispheric functional correlation in MS patients using a novel resting-state functional MRI (RS-fMRI) homotopic technique.
• To determine if these homotopic changes correlate with structural pathology in the Corpus Callosum (CC).

Main Methods:

• Twenty-four MS patients and 24 healthy controls underwent RS-fMRI and Diffusion Tensor Imaging (DTI) at 3T.
• Voxel-Mirrored Homotopic Connectivity (VMHC) was computed from RS-fMRI data to assess interhemispheric correlation.
• Fractional Anisotropy (FA) of CC segments was measured using DTI to quantify microstructural integrity.

Main Results:

• MS patients displayed abnormal homotopic connectivity patterns, with decreased VMHC in visual, somatosensory, and motor cortices.
• Increased VMHC was observed in regions like the insula, thalamus, pallidum, and cerebellum in MS patients.
• Global VMHC showed a moderate correlation with the average FA of the entire CC across all participants (r = 0.3; P = .03).

Conclusions:

• VMHC analysis shows potential for detecting interhemispheric coordination abnormalities in MS.
• Altered whole-brain homotopic RS-fMRI patterns in MS are partially associated with CC structural degeneration, as measured by FA.