Deep Brain Stimulation for Obsessive-Compulsive Disorder: Optimal stimulation sites

Background Deep brain stimulation (DBS) is a promising treatment option for treatment-refractory obsessive-compulsive disorder (OCD). Several stimulation targets have been used, mostly in and around the anterior limb of the internal capsule and ventral striatum (VC/VS). However, the precise target within this region remains a matter of debate. Methods Here, we retrospectively studied a multicenter cohort of 82 patients that underwent DBS of the VC/VS and mapped optimal stimulation sites in this region. Results DBS sweet-spot mapping performed on a discovery set of 58 patients revealed two optimal stimulation sites associated with improvements on the Yale-Brown Obsessive-Compulsive Scale, one in the anterior limb of the internal capsule that overlapped with a previously identified OCD-DBS response tract, and one in the region of the inferior thalamic peduncle and bed nucleus of the stria terminalis. Critically, the nucleus accumbens proper and anterior commissure were associated with beneficial but suboptimal clinical improvements. Moreover, overlap with the resulting sweet- and sour-spots significantly estimated variance in outcomes in an independent cohort of 22 patients from two additional DBS centers. Finally, beyond obsessive-compulsive symptoms, stimulation of the anterior site was associated with optimal outcomes for both depression and anxiety, while the posterior site was only associated with improvements of depression. Conclusions Our results suggest how to refine targeting of DBS in OCD and may be helpful in guiding DBS programming in existing patients.