Safety and efficacy of repetitive transcranial magnetic stimulation in the treatment of obsessive-compulsive disorder: A review

Objectives. Obsessive-compulsive disorder (OCD) is a chronic, often severe, neuropsychiatric disorder leading to a dramatic impairment in interpersonal and occupational functions. rTMS has been tried out in several studies in patients with OCD with different characteristics. In this paper, we review the safety and efficacy of rTMS in the treatment of mostly severe resistant OCD. Methods. A review of the English literature from 1966 to 2010 pertaining to rTMS in the treatment of OCD was conducted using MEDLINE by selectively entering the search terms "transcranial magnetic stimulation", "repetitive transcranial magnetic stimulation", "obsessive-compulsive disorder" and "OCD". Twelve studies including open and randomized, sham-controlled trials were included in this review. Results. Although available data about the use of rTMS in OCD treatment are quite heterogeneous in terms of sample size, study design, stimulus parameters used and stimulation areas targeted, promising findings regarding rTMS efficacy appeared for two structures based on recent controlled studies: the supplementary motor area and the orbitofrontal cortex. On the other hand, rTMS of the dorsolateral prefrontal cortex is not significantly effective when compared to sham rTMS. Conclusions. Three target areas have already been selected of which the supplementary motor area in particular and the orbitofrontal cortex seem to be the most promising in terms of potential efficacy and could more accurately be targeted with the help of neuronavigational techniques. Larger randomized controlled trials should be conducted in order to better clarify the therapeutic role of rTMS in OCD.