FRONTOSTRIATAL MEASUREMENT IN TREATMENT-NAIVE CHILDREN WITH OBSESSIVE-COMPULSIVE DISORDER

Background: Abnormalities in frontostriatal circuits have been implica ted in obsessive-compulsive disorder (OCD). Although OCD commonly emer ges during childhood or adolescence, few studies have examined frontos triatal anatomy in psychotropic-naive children with OCD near the onset of illness to determine the possible role of atypical developmental p rocesses in this disorder. Methods: Magnetic resonance imaging scans f rom 19 children with OCD who had not been exposed to psychotropic drug s, aged 7 to 18 years, and 19 case-matched healthy control subjects we re analyzed to determine the volumes of the following structures: pref rontal cortex, striatum (caudate and putamen), lateral and third ventr icles, and intracranial volume. Results: Patients with OCD had signifi cantly smaller striatal volumes and significantly larger third ventric le volumes than controls, but did not differ in prefrontal cortical, l ateral ventricular, or intracranial volumes. Striatal volumes were inv ersely correlated with OCD symptom severity but not illness duration. Conclusions: Our findings provide new evidence of abnormalities of the striatum in pediatric OCD. These results are preliminary, given the s mall sample size.