The effectiveness of deep transcranial magnetic stimulation to the medial prefrontal cortex and anterior cingulate cortex in obsessive-compulsive disorder patients

Studies investigating the effectiveness of Deep Transcranial Magnetic Stimulation (dTMS) on the treatment of Obsessive-Compulsive Disorder (OCD) have attracted attention in recent years. The aim of our study was to investigate the efficacy of 30 sessions of dTMS in the medial prefrontal cortex (mPFK) and anterior cingulate cortex (ASK) on high-frequency (20 Hz), 2 times a day, on obsessive-compulsive symptoms, accompanying depression and anxiety symptoms and reverse learning as splicing therapy in OCD patients. The study was completed with 29 patients who were admitted to Pamukkale University Habib Kızıltaş Psychiatric Hospital, diagnosed with OCD according to DSM-5 diagnostic criteria, and who did not respond adequately to treatment with at least two seratonin reuptake inhibitors (SGIs) of the appropriate duration and dose. OCD patients were randomized with the program called research randomizer at the beginning of the study, and dTMS was applied to 14 patients and imitation TMS was applied to 15 patients as double-blind and parallel groups. The study lasted three weeks for one participant, excluding the week afterward. At the beginning and end of TMS application, Yale-Brown Obsession Compulsion Scale (ICCCO), Dimensional Obsession Compulsion Scale (BOKÖ), Hamilton Depression Assessment Scale (HAM-D), Hamilton Anxiety Assessment Scale (HAM-A), Clinical Global Impression Scale (KGI-Ö) and Probabilistic Reverse Learning Test (OTE) were applied to the patients. In addition, standardized individual symptom provocation was applied to patients before each TMS session. At the beginning of the study, a questionnaire was made to each patient in which their thoughts about the treatment were evaluated, and no intervention was made to the existing drug treatments of the patients during the study. When the groups after TMS application are compared; ıt was observed that dTMS had an advantage over plecebo that made a significant difference in the total XVI and subscale scores of YBOKÖ. According to the percentage change in the total scores of the ICO, it was observed that the deep TMS group responded to the treatment at a rate of 35.7% and the imitation TMS group at a rate of 6.7%, while the deep TMS group responded to the treatment at a rate of 50% and the imitation TMS group at a rate of 6.7% according to the KGI-Ö. According to the total scale of the BOKÖ and the subscales of contagion/contamination, responsibility, unacceptable thoughts, it was seen that dTMS had a superiority that made a significant difference to imitation TMS. There was no significant difference between the two groups for the BODO symmetry/order subscale. While there was no significant difference between the two groups according to HAM-D, it was seen that the deep TMS group had a significant difference to the imitation TMS group according to HAM-A. When the OTÖT scores were evaluated, it was observed that significant results were obtained in the dTMS group itself in the total post-study trial, total trial for each block and average error categories for each rule change. When the post-treatment OTS scores were compared, it was found that the dTMS group was statistically superior to the imitation TMS in the correct trial and correct trial for each block categories. In conclusion, this study is the first study investigating the efficacy of applying high-frequency (20 Hz) dTMS to mPFK and ASK using double cone coil (DCC-03-125-C) on OCD patients. In our randomized, double-blind and parallel groups, our study revealed that dTMS was superior to imitation TMS, that it provided clinically significant improvement in OCD symptoms with the addition of drug therapy, that it provided benefits on anxiety and relatively depressive symptoms, and that it had a significant effect on learning on the contrary. Keywords: Deep transcranial magnetic stimulation, medial prefrontal cortex, anterior cingulate cortex, double cone coil (DCC-03-125-C), obsessive-compulsive disorder, individual symptom provocation