A voxel-based morphometric MRI study of stabilized obsessive-compulsive adolescent patients

The aim of this study was to determine whether treated stabilized adolescents with obsessive-compulsive disorder (OCD) present brain structure differences in comparison with healthy control subjects.

Twenty-seven adolescents with already-treated OCD and 27 healthy controls matched by age, sex and estimated intellectual level were assessed by means of psychopathological scales and magnetic resonance imaging (MRI). Axial three-dimensional T1-weighted images were obtained in a 1.5 T scanner and analyzed using optimized voxel-based morphometry (VBM).

Compared with controls, stabilized patients with OCD did not present any statistical differences in the whole brain. However, a small volume correction analysis yielded significant results that survived correction for multiple comparisons, showing decreased white matter (WM) volume in a small area of the parietal cortex (t=3.39, p=0.045 FWE (family wise error)-corrected) of OCD patients in comparison with healthy controls. There was no significant correlation between decreased WM volume in the parietal cortex and obsessive-compulsive symptomatology.

There were no global significant differences in either gray matter (GM) or WM. Small differences were found between adolescent patients with stabilized OCD and healthy controls as regards in WM volume in right parietal areas. The parietal lobe may play a role in the pathophysiology of OCD, even in clinically stabilized patients.