Outcomes in Lesion Surgery versus Deep Brain Stimulation in Patients with Tremor: A Systematic Review and Meta-analysis.

INTRODUCTION: Optimal surgical strategy for patients with tremor remains uncertain. We conducted a systematic review and meta-analysis evaluating randomized controlled trials of deep brain stimulation (DBS) and lesion surgery (LS) in treatment of tremor.

METHODS: We searched PubMed, Embase and the Cochrane database to include randomized clinical trials with either lesion surgery, deep brain stimulation, or controls. The outcomes were the change in tremor score, quality of life, cognitive function, and neuropsychiatric function. We used standardized mean differences (SMDs) to pool the outcomes.

RESULTS: Fifteen trials, including 1,508 patients, met eligibility criteria. We observed no significant difference in change of tremor scale (SMD -0.07, 95% CI: -0.38 - 0.24), quality of life (SMD -0.21, 95% CI: -0.69 - 0.27), cognitive function (SMD 0.06, 95% CI: -0.27 - 0.39) nor neuropsychiatric function (SMD -0.15, 95% CI: -0.49 - 0.19) between lesion surgery and stimulation surgery. We observed heterogeneity across studies during indirect comparison of quality of life. We identified a possible effect modifier: improvement in quality of life correlated with duration of disease (p = 0.035). We found focused-ultrasound LS was associated with a 0.70 SMD increase (p = 0.014) in quality of life versus DBS in an exploratory subgroup analysis by separating two studies with focused-ultrasound LS from other LS studies.

CONCLUSIONS: Although the main analysis showed that LS and DBS were equally effective in treatment of patients with tremor, an exploratory subgroup analysis indicated an improvement in quality of life with non-invasive focused-ultrasound surgery.