Gait and Balance After MRI-Guided High-Intensity Focused Ultrasound Thalamotomy for Treatment of Tremor

Although magnetic resonance imaging guided focused ultrasound (MRgFUS) thalamotomy has shown a robust safety and efficacy profile for tremor treatment, gait disturbances have been reported but often lack objective measurement. The aim of this study was to evaluate gait and balance outcomes in patients with essential tremor (ET)-only and tremor-dominant Parkinson's disease with or without ET (TDPD ± ET) who have undergone MRgFUS thalamotomy for treatment of their tremors, using validated, multidimensional measures.

This retrospective review included all consecutive patients who underwent MRgFUS thalamotomy between June 14, 2021, and February 1, 2023. Patients who did not have a preprocedure or postprocedure gait and balance evaluation, and those lost to follow-up, were excluded. Primary outcomes were changes in the preprocedural and postprocedural Tinetti gait and balance scores and timed up and go time at the 3-month visit. Additional outcomes included changes in ambulation time, steps taken to walk 30 feet, and clinical improvement.

Of 92 total patients (72 ET-only, 20 TDPD ± ET), the ET-only cohort had a median follow-up of 94 days (IQR 91-113), and the TDPD ± ET cohort had a follow-up of 99.5 days (IQR 92.25-119.00). In ET-only patients, significant improvements were observed in median Tinetti balance (pre 15 [IQR 12-16] vs post 15 [IQR 13-16], P = .031) and median 30-ft ambulation time (8.11 seconds [IQR 6.74-10.77] vs 8.06 seconds [IQR 6.21-10.23], P = .009), with no change in median Tinetti gait, Tinetti total scores, timed up and go time, or steps to ambulate 30-ft. In patients with TDPD ± ET, only the median Tinetti gait improved (9.00 [IQR 6.00-11.00] vs 9.50 [IQR 7.75-12.00], P = .004).

MRgFUS thalamotomy is associated with a low risk of gait/balance disturbances and may also improve these functions in patients with ET and TDPD ± ET. This supports MRgFUS as a viable treatment option.