**E**ff**ectiveness, Timing and Procedural Aspects of Cognitive Behavioral Therapy after Deep Brain Stimulation for Therapy-Resistant Obsessive Compulsive Disorder: A Systematic Review**

**Meltem Görmezo ˘glu 1,2, Tim Bouwens van der Vlis 2, Koen Schruers 3,4, Linda Ackermans 2,4, Mircea Polosan 5 and Albert F.G. Leentjens 3,4,\***


Received: 17 June 2020; Accepted: 22 July 2020; Published: 26 July 2020

**Abstract:** *Background and aim:* Deep brain stimulation (DBS) is an effective treatment for patients with severe therapy-resistant obsessive-compulsive disorder (OCD). After initiating DBS many patients still require medication and/or behavioral therapy to deal with persisting symptoms and habitual behaviors. The clinical practice of administering postoperative cognitive behavioral therapy (CBT) varies widely, and there are no clinical guidelines for this add-on therapy. The aim of this review is to assess the efficacy, timing and procedural aspects of postoperative CBT in OCD patients treated with DBS. *Method:* Systematic review of literature. *Results:* The search yielded 5 original studies, one case series and three reviews. Only two clinical trials have explicitly focused on the effectiveness of CBT added to DBS in patients with therapy-resistant OCD. These two studies both showed effectiveness of CBT. However, they had a distinctly different design, very small sample sizes and different ways of administering the therapy. Therefore, no firm conclusions can be drawn or recommendations made for administering CBT after DBS for therapy-resistant OCD. *Conclusion:* The effectiveness, timing and procedural aspects of CBT added to DBS in therapy-resistant OCD have hardly been studied. Preliminary evidence indicates that CBT has an added effect in OCD patients being treated with DBS. Since the overall treatment effect is the combined result of DBS, medication and CBT, future trials should be designed in such a way that they allow quantification of the effects of these add-on therapies in OCD patients treated with DBS. Only in this way information can be gathered that contributes to the development of an algorithm and clinical guidelines for concomittant therapies to optimize treatment effects in OCD patients being treated with DBS.

**Keywords:** deep brain stimulation; obsessive compulsive disorder; cognitive behavioral therapy
