Three-year follow-up of prospective trial of focused ultrasound thalamotomy for essential tremor.
Halpern, Casey H. MD; Santini, Veronica MD; Lipsman, Nir MD, PhD; Lozano, Andres M. MD, PhD; Schwartz, Michael L. MD; Shah, Binit B. MD; Elias, W. Jeff MD; Cosgrove, Garth R. MD; Hayes, Michael T. MD; McDannold, Nathan PhD; Aldrich, Christina RN, MSN; Eisenberg, Howard M. MD; Gandhi, Dheeraj MD; Taira, Takaomi MD, PhD; Gwinn, Ryder MD; Ro, Susie MD; Witt, Jennifer MD; Jung, Na Young MD; Chang, Jin Woo MD; Rosenberg, Jarrett PhD; Ghanouni, Pejman MD, PhD
93(24):e2284-e2293, December 10, 2019.
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Objective: To test the hypothesis that transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) thalamotomy is effective, durable, and safe for patients with medication-refractory essential tremor (ET), we assessed clinical outcomes at 3-year follow-up of a controlled multicenter prospective trial.
Methods: Outcomes were based on the Clinical Rating Scale for Tremor, including hand combined tremor-motor (scale of 0-32), functional disability (scale of 0-32), and postural tremor (scale of 0-4) scores, and total scores from the Quality of Life in Essential Tremor Questionnaire (scale of 0-100). Scores at 36 months were compared with baseline and at 6 months after treatment to assess for efficacy and durability. Adverse events were also reported.
Results: Measured scores remained improved from baseline to 36 months (all p < 0.0001). Range of improvement from baseline was 38%-50% in hand tremor, 43%-56% in disability, 50%-75% in postural tremor, and 27%-42% in quality of life. When compared to scores at 6 months, median scores increased for hand tremor (95% confidence interval [CI] 0-2, p = 0.0098) and disability (95% CI 1-4, p = 0.0001). During the third follow-up year, all previously noted adverse events remained mild or moderate, none worsened, 2 resolved, and no new adverse events occurred.
Conclusions: Results at 3 years after unilateral tcMRgFUS thalamotomy for ET show continued benefit, and no progressive or delayed complications. Patients may experience mild degradation in some treatment metrics by 3 years, though improvement from baseline remains significant.
Clinicaltrials.gov identifier: NCT01827904.
Classification of evidence: This study provides Class IV evidence that for patients with severe ET, unilateral tcMRgFUS thalamotomy provides durable benefit after 3 years.
(C) 2019 American Academy of Neurology