Voxel-based morphometry study of gray matter abnormalities in obsessive-compulsive disorder

Abstract

To examine regional abnormalities in the brains of patients with obsessive-compulsive disorder (OCD), we assessed the gray matter (GM) density using voxel-based morphometry (VBM). We compared magnetic resonance images (MRIs) acquired from 71 OCD patients and 71 age- and gender-matched normal controls and examined the relationship between GM density and various clinical variables in OCD patients. We also investigated whether GM density differs among the subtypes of OCD compared to healthy controls. We detected significant reduction of GM in the inferior frontal gyrus, the medial frontal gyrus, the insula, the cingulate gyrus, and the superior temporal gyrus of OCD patients. A significant increase in GM density was observed in the postcentral gyrus, the thalamus, and the putamen. Some of these regions, including the insular and postcentral gyrus, were also associated with the severity of obsessive- compulsive symptoms. These findings indicate that the frontal-subcortical circuitry is dysfunctional in OCD, and suggest that the parietal cortex may play a role in the pathophysiology of this disease.

Fig. 1

Statistical parametric mapping displaying gray matter (GM) density differences between patients with obsessive-compulsive disorder (OCD) and healthy controls. Significant changes of GM density with cluster of more than 20 voxels at <0.001, uncorrected for multiple comparisons are displayed. Note that significant decreases of GM density are identified in the right cingulate gyrus, bilateral frontal lobe, bilateral insular, and left superior temporal gyrus (A), whereas GM densities of the bilateral postcentral gyrus, right thalamus, and left putamen are significantly increased in patients with OCD (B) The color scale shows t values for each significant voxel.