Journal Article

Focused Ultrasound Thalamotomy for Refractory Essential Tremor: A Japanese Multicenter Single-Arm Study

Ohnishi, Takanori, Kondo, Kimito, Kamada, Hajime, Furukawa, Hironori, Mochizuki, Hideki, Yamaguchi, Toshio, Kishima, Haruhiko, Oshino, Satoru, Ohnishi, Hideyuki, Horisawa, Shiro, Kanemoto, Manabu, Hirabayashi, Hidehiro, Fukutome, Kenji, Sadamoto, Kazuhiko, Matsubara, Ichiro, Hori, Hiroki, Taira, Takaomi, Igase, Keiji, Yamada, Kazumichi, Abe, Keiichi

2021

Overview

Abstract BACKGROUND Several feasibility studies and a randomized, controlled, multicenter trial have demonstrated the safety and efficacy of unilateral transcranial magnetic resonance-guided focused ultrasound (FUS) lesioning of the ventral intermediate thalamic nucleus in treating essential tremor. OBJECTIVE To evaluate the safety and efficacy of FUS thalamotomy in a Japanese patient cohort through a prospective, multicenter, single-arm confirmatory trial. METHODS A total of 35 patients with disabling refractory essential tremor underwent unilateral FUS thalamotomy and were followed up for 12 post-treatment months. Safety was measured as the incidence and severity of treatment-related adverse events. Efficacy was measured as the tremor severity and quality of life improvements using the Clinical Rating Scale for Tremor and Questionnaire for Essential Tremor. RESULTS The mean skull density ratio (SDR) was 0.47. There was a significant decrease in the mean postural tremor score of the treated hand from baseline to 12 mo by 56.4% (95% CI: 46.7%-66.1%; P < .001), which was maintained at last follow-up. Quality of life improved by 46.3% (mean overall Questionnaire for Essential Tremor score of 17.4 [95% CI: 12.1-22.7]) and there were no severe adverse events. The most frequent adverse event was gait disturbance and all events resolved. CONCLUSION Unilateral FUS thalamotomy allowed significant and sustained tremor relief and improved the quality of life with an outstanding safety profile. The observed safety and efficacy of FUS thalamotomy were comparable to those reported in a previous multicenter study with a low SDR, and inclusion of the low SDR group did not affect effectiveness. Graphical Abstract Graphical Abstract

• Publisher: Oxford University Press,Wolters Kluwer Health, Inc
• Subject: Adult / Aged / Aged, 80 and over / Cohort Studies / Essential Tremor - diagnostic imaging / Essential Tremor - epidemiology / Essential Tremor - surgery / Feasibility studies / Female / High-Intensity Focused Ultrasound Ablation - methods / Humans / Japan - epidemiology / Magnetic Resonance Imaging - methods / Male / Middle Aged / Neurosurgery / Patient safety / Prospective Studies / Quality of life / Questionnaires / Surveys and Questionnaires / Thalamus - diagnostic imaging / Thalamus - surgery / Treatment Outcome / Tremor / Tremor (Muscular contraction) / Ultrasonic imaging