Intrabiliary Contrast-enhanced Ultrasonography Combined With Normal Saline Injection In The Detection Of Residual Stone Of Common Bile Duct

Objective: To investigate the value of intrabiliary contrast-enhanced ultrasonography combined with saline injection(CEUS-SJ)in the detection of residual stone after of common bile duct.Methods: Thirty-seven patients after undergoing laparoscopic or open common bile duct exploration and stone extraction with choledochal T-tube drainage,12 patients with percutaneous transhepatic cholangial drainage(PTCD)from September 2016 to July2018 were enrolled.Patients with contraindications of contrast-enhanced ultrasonography were excluded.All patients agreed to participate the study and signed informed consent forms.All the enrolled patients completed CEUS-SJ and choledochoscopy detection.The length and diameter of common bile duct before and after CEUS combined with normal saline injection were recorded and compared in all the 49 patients,and detected the residual stone.Results The full display rate of the common bile duct before and after CEUS-SJ18.37%(9/49)、87,76%(43/49).Before and after CEUS-SJ,the length of common bile duct were(2.54±1.89)cm and(4.59±2.24)cm,the diameter were(0.65±0.43)cm and(0.93±0.47)cm.The differences of the length and width of common bile duct before and after CEUS-SJ were statistically significant(t=7.81,4.81,both P<0.01).Only 4 cases of common bile duct stones were suspected before CEUS-SJ,and after CEUS-SJ,the other11 cases of common bile duct stones were suspected.Thirteen cases were confirmed by choledochoscopy detection.Two cases were false positive.Among the CEUS-negative patients,4 patients were confirmed positive by choledochoscopy.Using choledochoscopy detection as the diagnostic gold standard,CEUS-SJ had a sensitivity of 76.5%,a specificity of 93.8%,a positive predictive value of 0.87 and a negative predictive value of 0.88.The Youden index was 0.70,the accuracy was 87.8%and Kappa value was 0.885.Conclusion: CEUS-SJ can increase the display rate of common bile duct and improve the detection rate and range of residual stones after choledochal surgery.It could be a screening instrument of residual stone after of common bile duct.