Nuclear magnetic resonance study of obsessive-compulsive disorder.

Magnetic resonance imaging (MRI) of the brains of 32 patients who met the DSM-III criteria for obsessive-compulsive disorder and of 14 normal subjects frequently revealed abnormalities, but none was specific to obsessive-compulsive disorder. Spin-lattice relaxation time (T1) for right frontal white matter was prolonged in the patients compared to the control subjects, and the patients had greater right-minus-left T1 differences for frontal white matter. Right-minus-left T1 differences in the orbital frontal cortex were strongly correlated with symptom severity in the unmedicated patients and in the patients with family histories of obsessive-compulsive disorder.