Magnetic resonance-guided focused ultrasound (MRgFUS)-Thalamotomy for essential tremor: lesion location and clinical outcomes

Background: Factors predicting
\nclinical outcomes after MR-guided focused ultrasound
\n(MRgFUS)-thalamotomy in patients with essential tremor
\n(ET) are not well known.
\nObjective: To examine the clinical outcomes and their
\nrelationship with patients’ baseline demographic and
\nclinical features and lesion characteristics at 6-month
\nfollow-up in ET patients.
\nMethods: A total of 127 patients were prospectively
\nevaluated at 1 (n = 122), 3 (n = 102), and 6 months
\n(n = 78) after MRgFUS-thalamotomy. Magnetic resonance imaging (MRI) was obtained at 6 months (n = 60).
\nPrimary outcomes included: (1) change in the Clinical
\nRating Scale of Tremor (CRST)-A+B score in the treated
\nhand and (2) frequency and severity of adverse events
\n(AEs) at 6 months. Secondary outcomes included
\nchanges in all subitems of the CRST scale in the treated
\nhand, CRST-C, axial tremor (face, head, voice, tongue),
\nAEs, and correlation of primary outcomes at 6 months
\nwith lesion characteristics. Statistical analysis included
\nlinear mixed, standard, and logistic regression models.
\nResults: Scores for CRST-A+B, CRST-A, CRST-B in the
\ntreated hand, CRST-C, and axial tremor were improved
\nat each evaluation (P < 0.001). Five patients had severe
\nAEs at 1 month that became mild throughout the follow-up. Mild AEs occurred in 71%, 45%, and 34% of
\npatients at 1, 3, and 6 months, respectively. Lesion volume was associated with the reduction in the CRST-A
\n(P = 0.003) and its overlapping with the ventralis intermedius nucleus (Vim) nucleus with the reduction in
\nCRST-A+B (P = 0.02) and CRST-B (P = 0.008) at
\n6 months.
\nConclusions: MRgFUS-thalamotomy improves hand
\nand axial tremor in ET patients. Transient and mild AEs
\nare frequent. Lesion volume and location are associated
\nwith tremor reduction. © 2024 The Authors. Movement
\nDisorders published by Wiley Periodicals LLC on behalf
\nof International Parkinson and Movement Disorder
\nSociety.