Nahid Olfati1, Ali Shoeibi2, Ebrahim Abdollahian3, Hamideh Ahmadi4, Alireza Hoseini5, Saeed Akhlaghi6, Vida Vakili7, Mohsen Foroughipour8, Fariborz Rezaeitalab9, Mohammad-Taghi Farzadfard10, Parvaneh Layegh11, Shahrokh Naseri12. 1. Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: nahidolfati@gmail.com. 2. Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: shoeibia@mums.ac.ir. 3. Department of Psychiatry, Faculty of Medicine, Mashhad University of Medical Sciences, Psychiatry and Behavioral Sciences Research Center, Ibn-Sina Medical Center, Mashhad, Iran. Electronic address: abdollahiane@mums.ac.ir. 4. Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: ahmadih941@mums.ac.ir. 5. Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: hoseiniar931@mums.ac.ir. 6. Department of Psychiatry, Faculty of Medicine, Mashhad University of Medical Sciences, Psychiatry and Behavioral Sciences Research Center, Ibn-Sina Medical Center, Mashhad, Iran. Electronic address: akhlaghis1@mums.ac.ir. 7. Department of Community Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: VakiliV@mums.ac.ir. 8. Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: foroughipourm@mums.ac.ir. 9. Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: rezaeitalabF@mums.ac.ir. 10. Department of Neurology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: FarzadfardMT@mums.ac.ir. 11. Department of Radiology, Faculty of Medicine, Mashhad University of Medical Sciences, Quaem Medical Center, Mashhad, Iran. Electronic address: LayeghPr@mums.ac.ir. 12. Department of Medical Physics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
Abstract
BACKGROUND: There is controversial evidence about the effect of cerebellar low-frequency stimulation in patients with essential tremor (ET). OBJECTIVES: In this study we assessed safety and effectiveness of 1 Hz (low-frequency) cerebellar repetitive transcranial magnetic stimulation (rTMS) on tremor severity in patients with essential tremor in a sham-controlled crossover trial. METHODS: A total of 23 patients assigned into two groups to receive either sham (n = 10) or rTMS (n = 13) treatment, with crossing over after a two-month washout period. Intervention consisted of 900 pulses of 1 Hz rTMS at 90% resting motor threshold or the same protocol of sham stimulation over each cerebellar hemisphere for 5 consecutive days. Tremor severity was assessed by Fahn-Tolosa-Marin (FTM) scale at baseline and at days 5, 12 and 30 after intervention. The FTM consists of 3 subscales including tremor severity rating, performance of motor tasks, and functional disability. Carry-over and treatment effects were analyzed using independent samples t-test. RESULTS: There was no significant improvement in the total FTM scores in rTMS compared to the sham stimulation on day 5 (p = 0.132), day 12 (p = 0.574), or day 30 (p = 0.382). Similarly, FTM subscales, including tremor severity rating, motor tasks, and functional disability did not improve significantly after rTMS treatment. Mild headache and local pain were the most frequent adverse events. CONCLUSION: Although cerebellar rTMS seems to have acceptable safety when used in ET patients, this study could not prove any efficacy for it in reduction of tremor in these patients. Larger studies are needed to evaluate efficacy of this therapeutic intervention and to provide evidence about the optimal stimulation parameters.
RCT Entities:
BACKGROUND: There is controversial evidence about the effect of cerebellar low-frequency stimulation in patients with essential tremor (ET). OBJECTIVES: In this study we assessed safety and effectiveness of 1 Hz (low-frequency) cerebellar repetitive transcranial magnetic stimulation (rTMS) on tremor severity in patients with essential tremor in a sham-controlled crossover trial. METHODS: A total of 23 patients assigned into two groups to receive either sham (n = 10) or rTMS (n = 13) treatment, with crossing over after a two-month washout period. Intervention consisted of 900 pulses of 1 Hz rTMS at 90% resting motor threshold or the same protocol of sham stimulation over each cerebellar hemisphere for 5 consecutive days. Tremor severity was assessed by Fahn-Tolosa-Marin (FTM) scale at baseline and at days 5, 12 and 30 after intervention. The FTM consists of 3 subscales including tremor severity rating, performance of motor tasks, and functional disability. Carry-over and treatment effects were analyzed using independent samples t-test. RESULTS: There was no significant improvement in the total FTM scores in rTMS compared to the sham stimulation on day 5 (p = 0.132), day 12 (p = 0.574), or day 30 (p = 0.382). Similarly, FTM subscales, including tremor severity rating, motor tasks, and functional disability did not improve significantly after rTMS treatment. Mild headache and local pain were the most frequent adverse events. CONCLUSION: Although cerebellar rTMS seems to have acceptable safety when used in ET patients, this study could not prove any efficacy for it in reduction of tremor in these patients. Larger studies are needed to evaluate efficacy of this therapeutic intervention and to provide evidence about the optimal stimulation parameters.