Tremor Control and Patient Reported Outcomes after Bilateral Focused Ultrasound Thalamotomy for Essential Tremor

Abstract

Background: Staged bilateral magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is FDA approved to treat essential tremor (ET), but patient-reported outcomes and satisfaction data are limited. Objectives: We present tremor outcomes, patient-reported adverse effects, and satisfaction in a cohort of 30 treated patients. Methods: Patients underwent staged bilateral MRgFUS thalamotomy from 2020 to 2024, with minimum three-months of follow-up. Upper extremity tremor was assessed using the Clinical Rating Scale for Tremor Part B. Patients were asked directly about speech changes, sensory changes, gait disturbance, dysphagia, taste changes, ataxia, weakness, and satisfaction with bilateral treatment. Results: Thirty patients underwent staged bilateral MRgFUS, of which 25 (83%) have 6 months, 20 (67%) have 12 months, and 10 (33%) have 24+ months of follow-up. Tremor severity at baseline was similar bilaterally and was significantly improved bilaterally by treatment (P < 0.001); however, not as greatly on the second treated side. Twenty-six patients (87%) reported at least one new mild or moderate adverse effect after bilateral treatment; no severe adverse effects were reported. Notably, at 12 months 55% reported persistent speech changes, 30% reported persistent sensory changes, and 20% reported persistent gait disturbance. At 3 and 6 months of follow-up, more than 80% of patients reported that they would repeat second-side treatment in retrospect, but this declined to 67% at 12 months, and 60% at 24+ months. Conclusion: Significant bilateral tremor control was achieved after bilateral MRgFUS thalamotomy for ET, but rates of some adverse effects were higher than previously reported.