Neuroimaging assessment of basal ganglia volumes in Tourette Syndrome: a systematic review and meta-analysis

IntroductionAn increasing number of studies indicate that anatomical, physiological, and histological differences in the basal ganglia(BG) lie in the etiology of Tourette Syndrome(TS). However, the fact that there are very few studies on the anatomy of the BG in TS, small sample sizes, and unclear information as a consequence of these studies' contradictory findings is a significant gap in the scientific literature. The current systematic review and meta-analysis were performed to examine the differences in BG volumes between TS and controls.MethodThe protocol was registered with PROSPERO(CRD42023445845). Pertaining studies were ascertained via a search of the published literature in academic databases. The software Comprehensive Meta-Analysis was utilised for statistical analysis.Results527 articles were reached, and after the exclusion stages, 8 articles remained for the current systematic review and 7 articles for the quantitative meta-analysis. After evaluating each component of the BG individually, no difference was found between the BG volumes of controls and TS.ConclusionThe failure to discover the predicted volume difference can be explained by either the severity of the tic or the exclusion of comorbidity. The difference in BG volume is likely related to TS cases with more severe tics and severe comorbidities.