Is there potential for repetitive Transcranial Magnetic Stimulation (rTMS) as a treatment of OCD?

Obsessive-Compulsive Disorder (OCD) is a common and highly debilitating psychiatric disorder. Amongst OCD sufferers are a significant number (40-60%) of so-called non-responders who do not fully respond to commonly available treatments, which include medications (Selective Serotonin Reuptake Inhibitors-SSRIs) and cognitive behavior therapy (CBT). Modern 'neuromodulatory' techniques such as Deep Brain Stimulation (DBS), repetitive Transcranial Magnetic Stimulation (rTMS) and transcranial Direct Current Stimulation (tDCS) potentially offer alternative forms of treatment for OCD patients who either do not respond to, or are unable or unwilling to take SSRIs and undergo CBT. Although shown to be effective in treatment resistant OCD, DBS requires invasive neurosurgical procedures with associated risks. On the other hand, rTMS and tDCS are non-invasive forms of treatment, which are largely risk free, but the evidence of their efficacy so far is somewhat limited, with only small number of published studies. In this brief survey we will address the potential of rTMS as a therapeutic tool for OCD and review the published literature on the cortical targets for rTMS used so far. We will also discuss some of the newer variants of rTMS techniques only a few of which have been employed so far, and speculate whether there might be a place for rTMS as a standard treatment in OCD, along side CBT, SSRIs and DBS.