Glucose Consumption During Deep Brain Stimulation With Functional [18F]FDG-Brain-PET in Obsessive-Compulsive Disorder

Who May Qualify: - a score of 25 or higher on the Yale-Brown Obsessive Compulsive Scale - previous failure to respond to at least two medication trials with serotonin reuptake inhibitors at or, if tolerated, beyond the FDA maximum recommended dose for a minimum duration over at least ten weeks each. - at least one trial with tricyclic medication at or, if tolerated, beyond the FDA maximum recommended dose for a minimum duration over at least ten weeks each. - at least one trial of augmentation with antipsychotic medication, lithium, a benzodiazepine or buspirone - at least on trial of psychotherapy (cognitive behavioral therapy or comparable techniques) for at least 20 sessions - ability to provide written willing to sign a consent form Who Should NOT Join This Trial: - any history of current or past psychotic disorder - a manic episode within the preceding three years - any current clinically significant medical or neurological disorder, that is a contraindication against DBS - any disease that could lead to an altered glucose reactivity (e.g. diabetes) - any clinically significant preoperative MRI abnormality or inability to undergo presurgical MRI - current or unstable remitted substance abuse or dependence except nicotine - pregnancy or high risk of becoming pregnant during study duration (desire to have children) and refusal to utilize a proper method of contraception - Any current severe personality disorder except comorbid anankastic personality disorder - Inability to follow the study protocol or adhere to operational requirements - Current and unstable suicidality Always talk to your doctor about whether this trial is right for you.