Staged Bilateral Magnetic Resonance-Guided Focused Ultrasound Thalamotomy for Essential Tremor: Prospective...

Staged bilateral Magnetic Resonance-guided Focused Ultrasound (MRgFUS) thalamotomy is an incisionless option for medication-refractory essential tremor (ET). While the efficacy and safety of unilateral MRgFUS are established, evidence for bilateral treatment remains limited.

To evaluate the efficacy and safety of staged bilateral MRgFUS in a prospective single-centre observational cohort and to perform a systematic review and meta-analysis of the literature.

Consecutive ET patients undergoing second-side MRgFUS were prospectively assessed. The primary efficacy endpoint was the longitudinal change in Clinical Rating Scale for Tremor (CRST) A + B scores for the treated hand after FUS2, while safety was evaluated by collecting and grading adverse events (AEs). A systematic review identified published bilateral MRgFUS series; efficacy data were meta-analysed, while AEs were reported descriptively.

Fifteen patients (60% men; mean age 74.1 ± 8.9 years) underwent FUS2 28.9 ± 22.5 months after first-side treatment. At the 12-month evaluation, CRST A + B decreased from 21.0 to 8.8 (-58%), CRST C from 7.3 to 1.9 (-74.2%), and QUEST from 30.5 to 9.5 (-68.7%). Head and voice tremor were reduced by 73.8% and 40.3%, respectively. AEs were predominantly mild (95.2%) and transient (88%). Cognition at 1 year was globally preserved, with a selective decline in verbal episodic memory. Meta-analysis confirmed significant improvement in tremor severity.

Staged bilateral MRgFUS thalamotomy was associated with sustained tremor reduction, including midline tremor, functional improvement and acceptability, with a manageable safety profile. Overall, consistent with literature, these findings support its potential role as a therapeutic option in selected ET patients.