Transcranial magnetic stimulation over orbitofrontal cortex in obsessive compulsive disorder: A double-blind placebo-controlled trial

Abstract

In this study, the effectiveness of low frequency (1 Hz) rTMS application to the orbitofrontal cortex (OFC) was investigated in medication-resistant OCD. Thirty-four medication-resistant OCD patients were divided into two groups in a crossover design. One group started with active rTMS, while the other started with sham rTMS, before crossing over at two weeks. rTMS application was added to the pharmacological treatments used by the patients. While there was a significant decrease in YBOCS total scores in the group which received TMS between Week 0 and 2, the decrease in the sham TMS group did not reach significance. There was a statistically significant decrease in YBOCS total scores in both groups between Weeks 2 and 4. In addition, the two groups did not differ from each other in terms of percentage change in scale scores between Weeks 0 and 2, Weeks 2 and 4, and Weeks 0 and 4. The results of this study suggest that rTMS applied at 1 Hz targeting the OFC is not effective for medication-resistant OCD. Future studies with the use of coils allowing deeper stimulation, higher-frequency stimulation, and longer duration of treatment may provide useful information in this regard.