Gray Matter Volume Abnormalities and Clinical Correlates in OCD with Exclusive Washing Dimension

Abstract Objective Obsessive compulsive disorder (OCD) is increasingly being recognized as a heterogeneous disorder with various symptom dimensions. In order to understand the neurobiology of obsessive-compulsive disorder (OCD), it is important to understand the brain basis of homogeneous symptom groups. In this study we investigated the gray matter (GM) changes and correlates of an exclusively homogenous sample of OCD patients (washers with no other obsessive compulsive symptoms). Method We compared the structural MRI scans (3 T) using voxel-based morphometry (VBM) of washers (N = 35) with matched healthy controls (HC) (N = 39). Results We found volume deficits corresponding to right inferior frontal gyrus, parahippocampal gyrus and right anterior lobe of cerebellum among washers compared to HC. Among the washers, GM volume of right inferior frontal gyrus, right uncus of the limbic lobe, left cuneus and left superior temporal lobe had significant negative correlation with the illness severity score. Conclusion Examining homogenous sub-groups of OCD patients may help us further our understanding of neurobiology of OCD.