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 treatment 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 relevant 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 studies 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 responders and non-responders to specific protocols.
Part of the book: Transcranial Magnetic Stimulation in Neuropsychiatry