title: Intraoperative ultrasonography versus cholangiography during laparoscopic cholecystectomy: a prospective comparative study.
abstract: BACKGROUND
  The purpose of this study was to compare the functional utility of intraoperative ultrasonography (IOUS) and cholangiography (IOC) during a laparoscopic cholecystectomy for the treatment of gallstone disease.
  
  
  METHODS
  A prospective study comparing IOUS and IOC was carried out in 65 patients. Intraoperative ultrasonography was conducted first using a 7.5-MHz linear array probe. After IOUS, IOC was then conducted in all patients. The respective usefulness of IOUS and IOC in the identification of gallstones, detection of hepatobiliary structures, and demonstration of congenital anomalies was then compared.
  
  
  RESULTS
  Intraoperative ultrasonography was successful in all 65 patients, and IOC was successful only in 54. The time required for IOUS was significantly shorter (p < 0.0001) than for IOC. Intraoperative ultrasonography imaged the hepatic ducts and their confluence, the common hepatic duct, the common bile duct, and the ampulla of Vater in 97, 100, 97, and 51% of cases, respectively. Intraoperative cholangiography, on the other hand, depicted these structures in 85, 89, 100, and 94% of cases, respectively. Intraoperative ultrasonography demonstrated the cystic duct and its confluence in 94% of cases. Biliary anomalies were identified by IOUS in 12 patients and by IOC in 13. Intraoperative ultrasonography could detect the hilar vascular structures in most patients and visualized anomalies of the hepatic arteries in 5 patients. In this series, 5 patients had choledocholithiasis. The sensitivities, specificities, positive and negative predictive values, and accuracies in identifying these bile duct stones were 80, 98, 80, 98, and 97% by IOUS, and 80, 97, 67, 98, and 95% by IOC, respectively.
  
  
  CONCLUSIONS
  Intraoperative ultrasonography is superior to cholangiography with respect to its safety, shorter examination period, and ease of administration in all patients. In addition, IOUS is also better for identifying subtle anatomic detail. Intraoperative ultrasonography compares favorably with IOC in terms of utility in exploring bile ducts for stones. Intraoperative ultrasonography is an effective procedure for biliary exploration during a laparoscopic cholecystectomy.
authors.affiliation: Department of Surgery, Niigata University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ohtani
authors.forename: C
authors.initials: C
authors.lastname: Kawai
authors.forename: Y
authors.initials: Y
authors.lastname: Shirai
authors.forename: K
authors.initials: K
authors.lastname: Kawakami
authors.forename: K
authors.initials: K
authors.lastname: Yoshida
authors.forename: K
authors.initials: K
authors.lastname: Hatakeyama
mesh_terms: D002758:Cholangiography; D017081:Cholecystectomy, Laparoscopic; D002769:Cholelithiasis / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D016343:Monitoring, Intraoperative / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods