Background: Obsessive-compulsive disorder (OCD) is a highly prevalent, severe,
chronic, and disease. There is a need for alternative strategies for treatment-resistant OCD.
Objective: This review aims to assess the effect of brain stimulation techniques in OCD.
Method: We included papers published in peer-reviewed journals dealing with brain stimulation
techniques in OCD. We conducted treatment-specific searches for OCD (Technique AND ((randomized
OR randomised) AND control* AND trial) AND (magnetic AND stimulation OR (rTMS
OR dTMS)) AND (obsess* OR compuls* OR OCD)) on six databases, i.e., PubMed, Cochrane,
Scopus, CINAHL, PsycINFO, and Web of Science to identify randomised controlled trials and
ClinicalTrials.gov for possible additional results.
Results: Different add-on stimulation techniques could be effective for severely ill OCD patients
unresponsive to drugs and/or behavioural therapy. Most evidence regarded deep brain stimulation
(DBS) and transcranial magnetic stimulation (TMS), while there is less evidence regarding transcranial
direct current stimulation (tDCS), electroconvulsive therapy, and vagus nerve stimulation
(for these last two there are no sham-controlled studies). Low-frequency TMS may be more effective
over the supplementary motor area or the orbitofrontal cortex. DBS showed best results when
targeting the crossroad between the nucleus accumbens and the ventral capsule or the subthalamic
nucleus. Cathodal tDCS may be better than anodal in treating OCD. Limitations. Limitations include
methodologically inconsistent underpowered studies.
Conclusion: Different brain stimulation techniques are promising as an add-on treatment of refractory
OCD, although studies frequently reported inconsistent results. TMS, DBS, and tDCS could
possibly find some use with adequate testing, but their standard methodology still needs to be established.