Longitudinal Patient-Reported Outcomes in Essential Tremor and Tremor-Dominant Parkinson’s Disease Treated with MR-Guided Focused Ultrasound Vim Thalamotomy: A Real-World Cohort Study

Background/Objectives: MR-guided focused ultrasound (MRgFUS) Vim thalamotomy targets medication-refractory tremor in essential tremor (ET) and tremor-dominant Parkinson’s disease (PD). We examined longitudinal patient-reported outcomes alongside early motor changes. Methods: This retrospective cohort included 30 patients (12 ET, 18 PD). PDQ-39, PDQ-8, and EQ-VAS were analyzed using random-intercept mixed models. Multiplicity correction covered 16 visit contrasts, including four contrasts for a secondary. A sensitivity analysis included 11 participants with confirmed pretreatment W1 dates and numeric patient-reported data. Results: The paired motor analysis showed a median 12-point TRS reduction and median individual tremor improvement of 64.7% (n = 23; p < 0.001). Median original UPDRS Part III reductions in PD were 5 points OFF (p = 0.010) and 9 points ON medication (p = 0.004). Patient-reported outcomes were available for 25, 21, and 10 participants at W1, W2, and W3. No categorical-visit contrast met the corrected significance threshold in either the full-cohort or restricted analysis. Conclusions: MRgFUS was followed by substantial early tremor reduction and PD motor-score reductions compatible with clinically meaningful improvement against external benchmarks. This post hoc interpretation provides clinical context for motor change; the patient-reported analyses did not establish a consistent or durable quality-of-life benefit. Safety outcomes were not evaluated in this study.