**8. Conclusion-key results**

over 2 weeks utilizing a figure-8 coil with low frequency (1 Hz), 1200 pulses at 100% MT over the bilateral pre SMA. They were assessed 3 months after completing TMS. At the 2 week and 14 week assessments, the active group had a significant reduction of 35% in YBOCS scores

In 2014, Xiaoyan Ma published a randomized single-blind sham-controlled study that enrolled 46 subjects with moderate to severe OCD. The study's goal was to determine the treatment effect of using the patient's individualized alpha electroencephalogram (αEEG)-guided rTMS (αTMS) in OCD patients. Treatment was administered with a 9 cm circular coil placed over the midfrontal region. Twenty-five OCD patients received αTMS at 80% resting MT of the hand, 4 seconds stimulation, 56 seconds interval, 20 minutes stimulation daily, total pulses varied by patient's alpha between 648 and 872 pulses per day for 10 treatment sessions over 2 weeks. Twenty-one patients received sham stimulation using an unplugged coil with acoustic effects from another coil at a distance. At the end of treatment and the 1 week follow up, the obsession component of the YBOCS was significantly reduced in the active treatment group compared to the sham group [16]. In 2015, Mohammad Haghihagi published the results of a single blinded crossover trial of 21 OCD patients. Stimulation was administered at 20 Hz, 100% resting right hand MT, 1.5 second train, 25 trains, totaling 750 pulses, 5 days a week for 2 weeks. Sham stimulation was done with the coil angled away from the skull. After 2 weeks, patients switched conditions for an additional 2 weeks. In both groups, the patient's YBOCS improved after the active rTMS

In 2016, Khaled Elbeh randomized 45 patients into a trial to evaluate the effects of different rTMS frequencies over the right DLPFC at 100% resting left hand MT using a figure-8 coil. Fifteen patients received low frequency (1 Hz), 15 high frequency (10 Hz), and 15 received sham. The operators were not blinded. All groups were administered 10 sessions over 2 weeks of 2000 pulses each at 100% MT; then, patients were followed for 3 months post rTMS. The low frequency group but not the high frequency group's YBOCS was significantly different

In 2016, Emily Hawken published a two-site randomized, placebo-controlled clinical trial for patients with refractory OCD using low frequency rTMS to the bilateral SMA. Ten patients received active and 12 patients were in the placebo group, where the operators rotated the coil away from the skull. rTMS was administered at 1HZ, 110% of resting hand MT, 1200 pulses for 25 sessions over 6 weeks with a figure-8 coil. Active TMS recipients obtained significant reductions in their YBOCS compared to sham. Benefits were maintained for 6 weeks after treatment [19]. This is the third small sham-controlled study showing the benefits low fre-

In 2016, Ho Jun Seo published a 3-week single-blind study of low frequency rTMS to the right DLPFC with a figure-8 coil (Tamas, Remed). Fourteen patients received active and 13 patients received sham rTMS, 1 Hz, 1200 pulses, 100%MT of the left hand 5 days a week for 3 weeks.

In 2016, Stefano Pallanti published the results of an open-label trial with 50 patients with SSRI refractory OCD. Patients were randomized into either the TAU (treatment as usual) (n = 25) or rTMS (n = 25) groups. The TAU group was treated with antipsychotic drugs. In the rTMS

The active group had a significant YBOCS reduction compared to sham [20].

compared to the sham group who had a 6.2% reduction [15].

98 Transcranial Magnetic Stimulation in Neuropsychiatry

condition and not during the sham condition [17].

than sham. The effects did not last 3 months [18].

quency figure-8 rTMS over the SMA.

OCD is uniquely suited for intervention with TMS. However, rTMS interventions in OCD that focus on the lateral prefrontal cortices in both high and low frequency are not consistently efficacious. Most of the small sham-controlled studies treating the SMA, left DLPFC, and right DLPFC with low frequency as well as high frequency showed benefit. This is consistent with the results of a recently published meta-analysis. The meta-analysis noted the right DLPFC had a greater therapeutic effect than other treatment locations [27]. The next step should be a fully blinded (including the operators) sham-controlled multicenter study of low frequency rTMS to the SMA (the pre-SMA is the anterior portion of the SMA, and it is a midline region so it is always treated bilaterally even with a figure-8 coil). Two high frequency, high intensity studies using the HAC/H7 deep rTMS coil showed efficacy for OCD including a multisite study for FDA clearance. We await the detailed presentation of those results.

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TMS for OCD

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[9] Sachdev PS et al. Right versus left prefrontal transcranial magnetic stimulation for obsessive-compulsive disorder: A preliminary investigation. The Journal of Clinical Psy-

[10] Prasko J et al. The effect of repetitive transcranial magnetic stimulation (rTMS) on symptoms in obsessive compulsive disorder. A randomized, double blind, sham controlled

[11] Sachdev PS et al. Repetitive transcranial magnetic stimulation for the treatment of obsessive compulsive disorder: A double-blind controlled investigation. Psychological

[12] Ruffini C et al. Augmentation effect of repetitive transcranial magnetic stimulation over the orbitofrontal cortex in drug-resistant obsessive-compulsive disorder patients: A controlled investigation. Primary Care Companion to the Journal of Clinical Psychiatry. 2009;

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Further directions for the field include optimizing stimulation parameters for greater efficacy. What state should the circuitry be in during the stimulation? Does the treatment have durability or is maintenance necessary? If children and adolescents are treated early will it change the trajectory of their illness? Does the same protocol work for OCD related disorders such as hoarding, trichotillomania and body dysmorphic disorder? Does this work for OCD without insight or with delusions? Does it help with tics? What happens to the neural circuitry of the OCD patients responding to TMS? Can non-responders benefit from an individualized protocol? Can we predict responders from non-responders before we go through an entire treatment course?
