efficacy and adverse events of bilateral single-shot vc/vs gamma capsulotomy for ocd: a pilot study

Conditions: Obsessive-compulsive Disorder

Summary: up to 40% of obsessive-compulsive disorder (ocd) patients do not respond to conventional treatments (medications or behavior therapy). for some of them, a neurosurgical treatment can be indicated. a previous study, employing bilateral double-shot ventral capsular/ventral striatal (vc/vs) gamma capsulotomy (gvc) for ocd has shown that this radiosurgical technique is potentially efficacious and relatively safe. however, a few patients may develop complications associated to radionecrosis (eg., brain cysts) in a long-term follow-up, which are probably associated to lesion volumes. another study, with the preliminary results of smaller vc/vs gamma capsulotomy lesions has suggested that this procedure is safe and remains efficacious. our aim is to investigate the efficacy and safety profiles of smaller, single-shot vc/vs gamma capsulotomy for ocd. this study will support the development of a future double-blind, randomized clinical trial of single-shot vc/vs gamma capsulotomy.


Eligibility criteria:
inclusion criteria: * a dsm-v diagnosis of ocd as the main diagnostic entity. if comorbid axis i or ii disorders are present, ocd symptoms are the most troublesome among disorders. * age range between 18 and 65 years old. * at least 5 years of ocd symptoms. * "yale-brown obsessive-compulsive scale" (ybocs) scores greater than 26 (or greater than 13, for isolated obsessions or compulsions). * refractoriness criteria fulfilled. * to be accepted by the "best estimate" method as a treatment refractory patient. it consists in the careful examination of each patient's history by two ocd specialists, so as to confirm refractoriness status. refractoriness criteria: * at least 3 serotonin reuptake inhibitors (selective or not) have been tried before. one of these trials must have included clomipramine. all drugs were used for a minimum of 12 weeks, at the maximum doses or the maximally tolerated doses. * previous participation in a cognitive behavior therapy program (exposure and response prevention), for a minimum of 20 hours' time; or participation for some time, without subsequent adherence, due to severe ocd symptoms, and acceptance of the independent review board. * ybocs scores reductions after adequate drug therapy and psychotherapy not better than 25 %, or confirmation of no clinical improvements by the mental health professionals who were responsible for the treatments of the patient. * by the end of adequately conducted pharmacological trials, "clinical global impression" (cgi) scores not better than minimal improvement. * previous use of at least two antidepressant augmentation strategies (such as the association of a typical or atypical antipsychotic, another serotonin reuptake inhibitor, a benzodiazepine, an anticonvulsant or an antiglutamatergic medication), in adequate doses for a sufficient period of time, without satisfactory responses. exclusion criteria: * less than 18 years or more than 65 years of age. * past history of head injury, with posttraumatic amnesia. * past or general medical condition, or neurological illness with brain compromise (severe and in active phase) * history of physiological effects of a substance, as determinant of psychopathological symptoms, or cumulative signs of alcohol or drug abuse in the central nervous system (such cortical atrophy), confirmed by a neuroimaging scan. * pregnancy or lactation. * refusal to participate in radiosurgical procedures. * refusal to sign the patient information and consent form, or refusal to take part in this study. * history of mental retardation and/or being unable to understand the patient information and consent form, confirmed by poor performance on neuropsychological tests.