Deep brain stimulation for Tourette syndrome: a systematic review and meta-analysis

Deep brain stimulation (DBS) has emerged as a promising neuromodulatory therapy for patients with refractory Tourette syndrome (TS). Various brain targets-including the globus pallidus internus (GPi) and several thalamic nuclei-have been explored, yet the comparative efficacy of DBS in different targets remain unclear. This meta-analysis aims to evaluate the clinical efficacy of DBS in TS and assess symptom improvements across different stimulation targets. A systematic search of PubMed, Embase, and Web of Science identified studies published between October 2014 and September 2025. Study quality was assessed using the French and Gronseth classification system. Outcomes of interest included pre- and postoperative scores on the Yale Global Tic Severity Scale (YGTSS) and Yale-Brown Obsessive Compulsive Scale (YBOCS). A total of 22 studies involving 358 patients were included in this meta-analysis. Mean YGTSS scores decreased from 69.19 ± 18.04 preoperatively to 35.88 ± 17.23 postoperatively. There was an average 48% reduction in YGTSS scores. DBS led to a substantial reduction in tic severity (YGTSS: GPi, SMD = 2.29, P < 0.00001; thalamus, SMD = 2.33, P < 0.0001). Within the GPi subgroup, stimulation of the anteromedial GPi (amGPi) resulted in significantly better benefits (SMD = 3.01, P < 0.00001) compared to the posterior-ventrolateral GPi (pvlGPi), which did not reach statistical significance (SMD = 1.23, P = 0.05). YBOCS scores decreased from a mean of 17.38 ± 6.15 preoperatively to 9.16 ± 4.12 postoperatively. The average reduction in YBOCS scores was 47%. Obsessive-compulsive disorder (OCD) symptoms also showed significant improvement following DBS (overall YBOCS, SMD = 0.94, P < 0.00001; amGPi, SMD = 1.49, P = 0.004; pvlGPi, SMD = 0.72; P = 0.006). DBS is an effective and target-sensitive intervention for TS, alleviating both motor tics and obsessive-compulsive symptoms. Compared to therapies such as pvlGPi and thalamic-DBS, amGPi-DBS may demonstrate greater therapeutic potential compared with pvlGPi-DBS, suggesting its potential advantage in modulating the associated circuits involved in the pathophysiology of TS.