Gamma ventral capsulotomy for obsessive-compulsive disorder: a randomized clinical trial

Abstract

Importance: Select cases of intractable obsessive-compulsive disorder (OCD) have undergone neurosurgical ablation for more than half a century. However, to our knowledge, there have been no randomized clinical trials of such procedures for the treatment of any psychiatric disorder.

Objective: To determine the efficacy and safety of a radiosurgery (gamma ventral capsulotomy [GVC]) for intractable OCD.

Design, setting, and participants: In a double-blind, placebo-controlled, randomized clinical trial, 16 patients with intractable OCD were randomized to active (n = 8) or sham (n = 8) GVC. Blinding was maintained for 12 months. After unblinding, sham-group patients were offered active GVC.

Interventions: Patients randomized to active GVC had 2 distinct isocenters on each side irradiated at the ventral border of the anterior limb of the internal capsule. The patients randomized to sham GVC received simulated radiosurgery using the same equipment.

Main outcomes and measures: Scores on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the Clinical Global Impression-Improvement (CGI-I) Scale. Response was defined as a 35% or greater reduction in Y-BOCS severity and "improved" or "much improved" CGI-I ratings.

Results: Three of 8 patients randomized to active treatment responded at 12 months, while none of the 8 sham-GVC patients responded (absolute risk reduction, 0.375; 95% CI, 0.04-0.71). At 12 months, OCD symptom improvement was significantly higher in the active-GVC group than in the sham group (Y-BOCS, P = .046; Dimensional Y-BOCS, P = .01). At 54 months, 2 additional patients in the active group had become responders. Of the 4 sham-GVC patients who later received active GVC, 2 responded by post-GVC month 12. The most serious adverse event was an asymptomatic radiation-induced cyst in 1 patient.

Conclusions and relevance: Gamma ventral capsulotomy benefitted patients with otherwise intractable OCD and thus appears to be an alternative to deep-brain stimulation in selected cases. Given the risks inherent in any psychiatric neurosurgery, such procedures should be conducted at specialized centers.

Trial registration: clinicaltrials.gov Identifier: NCT01004302.