Structural brain MR imaging changes associated with obsessive-compulsive disorder in patients with multiple sclerosis

Area of Science:

• Neuroscience
• Neurology
• Psychiatry

Background:

• Multiple Sclerosis (MS) frequently presents with psychiatric symptoms, including Obsessive-Compulsive Disorder (OCD).
• OCD significantly impacts the daily lives of patients with MS.
• The widespread gray matter (GM) and white matter (WM) involvement in MS is hypothesized to contribute to psychiatric conditions like OCD.

Purpose of the Study:

• To investigate the relationship between GM and WM tissue damage and the presence of OCD in patients with MS.
• To identify specific brain structural changes associated with OCD in the MS population.

Main Methods:

• The study included 16 patients with relapsing-remitting MS and OCD, and 15 matched controls with MS but no psychiatric disorders.
• Magnetic Resonance (MR) imaging utilized 3D T1-weighted, Diffusion Tensor Imaging (DTI), and conventional MRI sequences.
• Image analysis employed SPM5, FSL, and Jim 5.0 software for evaluating Voxel-Based Morphometry (VBM), Tract-Based Spatial Statistics (TBSS), and lesion volumes (LV).

Main Results:

• VBM analysis revealed reduced GM volume in the right inferior and middle temporal gyri, and the inferior frontal gyrus in the OCD group compared to controls.
• No significant differences in fractional anisotropy (FA) values were detected between the groups using TBSS.
• Global and regional lesion volumes (LV) did not differ significantly between the OCD and control groups.

Conclusions:

• OCD in patients with MS is associated with localized gray matter damage in the right frontotemporal cortex.
• White matter integrity and overall lesion load do not appear to be primary drivers of OCD in this MS cohort.
• Findings suggest a specific neuroanatomical basis for OCD in MS, implicating right frontotemporal structures.