Evaluation of diagnostic yield of EUS among patients with asymptomatic common bile duct dilation: systematic review and meta-analysis

Background and Aims: Common bile duct (CBD) dilation is a frequent indication for EUS. Among asymptomatic individuals, biliary dilation may not be clinically significant; however, EUS is often relied on for the exclusion of benign and malignant pathology that might require further intervention. The yield of EUS evaluation for this indication is not well characterized and has significant implications for health resource utilization because asymptomatic biliary dilation is prevalent. Through this systematic review, we sought to appraise the yield of EUS evaluation of asymptomatic patients with radiologic evidence of isolated CBD dilation. Methods: A protocolled search (PROSPERO: CRD42020193428) extracted original studies from the Cochrane Library, Ovid Embase, Google Scholar, Ovid Medline, PubMed, Scopus, and Web of Science Core Collection that described diagnostic yield of EUS among asymptomatic patients with biliary dilation. Cumulative EUS diagnostic yield was calculated through meta-analysis of proportions using inverse variance methods and a random-effects model. Results: Of 2616 studies, 8 delineated the EUS yield among 224 asymptomatic patients. The cumulative yield of EUS for any pathology was 11.2% (95% confidence interval [CI], 3.6%- 21.6%). The EUS yield for benign etiologies was 9.2% (95% CI, 1.1%-21.9%), of which choledocholithiasis comprised 3.4% (95% CI, 0%-11.2%) and malignant etiologies.5% (95% CI, 0%-3.4%) of cases. Conclusions: EUS in patients with asymptomatic CBD dilation does yield findings of choledocholithiasis and malignancy, albeit at low rates. A cost-effectiveness analysis is warranted to further guide clinical decision-making in this area.