Microstructural white matter abnormalities in obsessive-compulsive disorder: A coordinate-based meta-analysis of...

Area of Science:

• Neuroimaging
• Neuropsychiatry
• Radiology

Background:

• Diffusion tensor imaging (DTI) findings in obsessive-compulsive disorder (OCD) lack conclusive evidence.
• White matter (WM) microarchitecture alterations are suspected in OCD patients.

Purpose of the Study:

• To conduct a comprehensive meta-analysis of DTI studies to identify WM microarchitecture changes in OCD.
• To compare differences between voxel-based analysis (VBA) and tract-based spatial statistics (TBSS) for DTI data.

Main Methods:

• Systematic search for DTI studies reporting fractional anisotropy (FA) alterations in OCD versus healthy controls (HC).
• Seed-based d mapping (SDM) used for meta-analysis of microstructural WM abnormalities.
• Subgroup meta-analysis to explore methodological differences between VBA and TBSS.

Main Results:

• 30 studies (855 patients, 875 HC) were included.
• OCD patients showed significantly decreased FA in the right cerebellar lobule, corpus callosum (CC), left superior frontal gyrus, right gyrus rectus, left superior longitudinal fasciculus, and right lenticular nucleus.
• VBA subgroup analysis revealed widespread FA reductions, while TBSS subgroup analysis showed significant FA reductions only in the CC.

Conclusions:

• Pooled meta-analysis indicates microstructural abnormalities in distributed WM tracts in OCD patients.
• Heterogeneous results were observed between VBA and TBSS methodologies in DTI analysis for OCD.