Abstract:Objective: To investigate the application value of intrabiliary contrast-enhanced ultrasonography (CEUS) in residual stone detection following choledochal surgery. Methods: Forty-one patients readmitted after undergoing open or laparoscopic common bile duct exploration and stone extraction with choledochal T-tube drainage, and 10 patients undergoing stone extraction through sinus tract dilation after percutaneous transhepatic cholangial drainage (PTCD) from August 2016 to January 2018 were enrolled. All patients underwent intrabiliary CEUS and X-ray cholangiography before choledochoscopic exploration through T-tube sinus tract or dilated PTCD sinus tract after admission. The length and diameter of the common bile duct before and after CEUS combined with saline injection were recorded. Using the results of choledochoscopic exploration as a golden standard for residual stones, the accuracies of the other two methods for residual stone detection were analyzed. Results: All the three examinations were completed in these patients. The full length of the common bile duct was exposed in 92.2% (47/51) patients under CEUS combined with saline injection. Using the results of choledochoscopic exploration as a standard, the coincidence rate of residual stone detection was 88.2% (45/51) for CEUS, with a sensitivity of 78.3%, specificity of 96.4% and κ value for the consistency of 0.76; the coincidence rate of residual stone detection was 82.4% (42/51) for X-ray cholangiography, with a sensitivity of 60.9%, specificity of 100% and κ value for the consistency of 0.63. Conclusion: Intrabiliary CEUS for residual stone detection after T-tube placement or PTCD sinus tract dilation can effectively observe the full length of the common bile duct and the residual stones inside, and its residual stone detection rate can be improved by combination with X-ray cholangiography.