THE EFFICACY OF DEEP REPETITIVE TRANSCRANIAL MAGNETIC STIMULATION OVER THE MEDIAL PREFRONTAL CORTEX IN OBSESSIVE COMPULSIVE DISORDER: RESULTS FROM AN OPEN-LABEL STUDY

Background Significant numbers of patients with obsessive compulsive disorder (OCD) respond minimally to currently available treatments. Furthermore, the application of both high- and low-frequency repetitive transcranial magnetic stimulation (rTMS) to dorsolateral prefrontal cortex has shown to be ineffective in the reduction of OCD symptoms. In this study, we instead targeted the medial prefrontal cortex (mPFC) and applied low-frequency rTMS to patients with OCD and assessed their clinical response. Methods In an open-label design, 10 OCD patients with no other current axis I psychiatric disorders were recruited. Twelve hundred pulses of 1-Hz frequency were applied over the mPFC (Brodmann areas 24 and 32) using a double-cone coil for 10 days. Regions of interest were located on participants' MRIs using neuronavigation software. Patients' symptoms were rated using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Results All patients demonstrated improvement in their OCD symptoms after 10 sessions of rTMS as shown by a mean improvement in Y-BOCS score of 39% (SD = 15%; P < .001, F = 62.95). This improvement persisted 1 month following the last session of rTMS. Conclusions Our results suggest the use of low frequency deep rTMS as a promising and robust intervention in OCD symptom reduction. However, this study is limited by its open-label nature and its lack of a control group, so further randomized clinical trials are needed to confirm these results.