Multicenter voxel-based morphometry mega-analysis of structural brain scans in obsessive-compulsive disorder.

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Structural neuroimaging studies in obsessive-compulsive disorder (OCD) have yielded inconsistent findings regarding brain volume differences.
• Previous research has been limited by smaller sample sizes, necessitating larger, collaborative efforts.

Purpose of the Study:

• To investigate regional gray and white matter volume variations in a large cohort of adult patients with OCD compared to healthy controls.
• To examine the relationship between these brain volume differences and demographic and clinical characteristics.

Main Methods:

• A multicenter voxel-based morphometry mega-analysis utilizing 1.5-T structural T1-weighted MRI scans.
• Comparison of regional brain volumes between 412 adult OCD patients and 368 healthy subjects from the International OCD Brain Imaging Consortium.

Main Results:

• OCD patients demonstrated significantly smaller bilateral frontal gray and white matter volumes, including the dorsomedial prefrontal cortex, anterior cingulate cortex, and inferior frontal gyrus.
• Increased cerebellar gray matter volume was observed bilaterally in OCD patients compared to controls.
• Significant group-by-age interactions were found in the putamen, insula, orbitofrontal cortex, and temporal cortex, indicating differential age-related volume changes.

Conclusions:

• Findings partially support fronto-striatal models of OCD and provide novel neuroanatomical insights.
• Observed age-related volume changes may reflect altered neuroplasticity due to compulsive behaviors, anxiety, or compensatory mechanisms for cognitive dysfunction.