title: Diagnostic Accuracy of Transcranial Sonography of the Substantia Nigra in Parkinson's disease: A Systematic Review and Meta-analysis.
abstract: A large number of articles have reported substantia nigra hyperechogenicity in Parkinson's disease (PD) and have assessed the diagnostic accuracy of transcranial sonography (TCS); however, the conclusions are discrepant. Consequently, this systematic review and meta-analysis aims to consolidate the available observational studies and provide a comprehensive evaluation of the clinical utility of TCS in PD. Totally, 31 studies containing 4,386 participants from 13 countries were included. A random effects model was utilized to pool the effect sizes. Meta-regression and sensitivity analysis were performed to explore potential heterogeneity. Overall diagnostic accuracy of TCS in differentiating PD from normal controls was quite high, with a pooled sensitivity of 0.83 (95% CI: 0.81-0.85) and a pooled specificity of 0.87 (95% CI: 0.85-0.88). The positive likelihood ratio, the negative likelihood ratio and diagnostic odds ratio were calculated 6.94 (95% CI: 5.09-9.48), 0.19 (95% CI: 0.16-0.23), and 42.89 (95% CI: 30.03-61.25) respectively. Our systematic review of the literature and meta-analysis suggest that TCS has high diagnostic accuracy in the diagnosis of PD when compared to healthy control.
authors.affiliation: Department of Neurology &Institute of Neurology, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.
authors.forename: Dun-Hui
authors.initials: DH
authors.lastname: Li
authors.affiliation: Department of Neurology &Institute of Neurology, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.
authors.forename: Ya-Chao
authors.initials: YC
authors.lastname: He
authors.affiliation: Department of Neurology &Institute of Neurology, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Neurology &Institute of Neurology, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China.
authors.forename: Sheng-Di
authors.initials: SD
authors.lastname: Chen
mesh_terms: D006801:Humans; D010300:Parkinson Disease / Q000175:diagnosis*; D017594:Publication Bias; D012372:ROC Curve; D015203:Reproducibility of Results; D013378:Substantia Nigra / Q000473:pathology*; D017585:Ultrasonography, Doppler, Transcranial