Magnetic resonance-guided focused ultrasound ventral intermediate thalamotomy for Tremor-Dominant Parkinson's disease: a systematic review and meta-analysis.

Introduction: Tremor-dominant Parkinson's Disease (TDPD) has a slower neurological decline compared to other phenotypes of the disease, but significantly impacts daily activities and is often less responsive to standard medications. Magnetic Resonance-guided Focused Ultrasound (MRgFUS) lesioning of the Ventral Intermediate (VIM) nucleus of the thalamus may alleviate symptoms for these patients.

Methods: A systematic review and meta-analysis of English-language studies from PubMed, Cochrane, and Embase were conducted, assessing the efficacy and safety of MRgFUS VIM thalamotomy in TDPD patients. Tremor scores were evaluated using the Clinical Scale Rating for Tremor and the Movement Disorders Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRSIII). Neuropsychological outcomes were measured using the Parkinson Disease Questionnaire (PDQ) and the Montreal Cognitive Assessment. This analysis adhered to Cochrane and PRISMA guidelines.

Results: Thirteen studies with 211 patients were included. MDS-UPDRSIII scores showed significant improvement at 1, 6, and 12 months post-MRgFUS, respectively: (MD -8.92 points, 95% CI: -15.44 to -2.40, p < 0.01; MD -7.39 points, 95% CI: -11.47 to -3.30, p < 0.01; MD -10.66 points, 95% CI: -16.89 to -4.43, p < 0.01). PDQ scores at baseline compared to 6 months post-treatment also indicated a significant improvement (SMD - 0.86, 95% CI: -1.21 to -0.50, p < 0.01). Neurological adverse events were generally mild and transient, with gait instability and sensory deficits being the most common.

Conclusion: This meta-analysis demonstrates significant improvements in tremor and neuropsychological outcomes following MRgFUS VIM thalamotomy in TDPD patients, with adverse events being typically mild and transient.