Evidence for striatal modulation in the presence of fixed cortical injury in obsessive-compulsive disorder (OCD)

A patient with obsessive-compulsive disorder (OCD) onset resulting from a traumatic head injury underwent longitudinal brain imaging evaluation. Structural and functional brain imaging studies were repeatedly performed before and after treatment. Computerized tomography (CT) demonstrated bilateral prefrontal contusions immediately following the trauma and prior to the onset of OCD. Magnetic resonance imaging (MRI) demonstrated bilateral cortical abnormalities in the prefrontal and anterior-temporal regions a few months following the onset of OCD. Almost concurrently, single photon emission computerised tomography (SPECT) demonstrated bilateral perfusion deficits in fronto-temporal regions, and asymmetric increased perfusion in the anterior striatum. Six months later, after clinical improvement, a second SPECT study demonstrated improvement of brain perfusion, mostly in the striatum. The reflection of these results on a possible model of brain pathogenesis in OCD, and the role of brain imaging in neuropsychiatric evaluation, are demonstrated.