TMS for OCD

Abstract

Introduction: Obsessive compulsive disorder (OCD) is a common disabling condition, which greater than 40% of patients do not respond to the available treatment options. Imbalances in the cortical-striatal-thalamic-cortical circuits have proven to be useful psychosurgical treat- ment targets making this circuit disorder an optimal target for intervention with TMS. Methods: PubMed and clinicaltrials.gov were reviewed for sham-controlled therapeutic rTMS studies for OCD. Results: Eighteen relevant studies are presented in a narrative fashion along with rel- evant methodological details, and distinctions. Conclusions: High and low frequency stimulation to lateral prefrontal cortices does not appear to have consistent efficacy in the small studies done to date. Several small stud- ies with non-blinded operators suggest that low frequency high intensity rTMS to the supplementary motor area with a figure-8 coil reduces OCD symptoms. A fully blinded multicenter center study is warranted to confirm this finding. A promising pilot study and a subsequent multicenter study of high frequency high intensity deep rTMS with the HAC/H7 coil to the bilateral prefrontal orbitofrontal and anterior cingulate cortices were completed with positive results. Many areas of uncertainty remain, such as the optimal state of the circuitry during stimulation and identifying a priori biomarkers for respond- ers and non-responders to specific protocols.