title: A prospective single-blinded controlled study comparing laparoscopic ultrasound of the common bile duct with operative cholangiography.
abstract: BACKGROUND
  Ultrasound examination of the bile duct during cholecystectomy compares well with operative cholangiography. Studies so for have not been blinded, nor has the stone content been validated immediately. We have, therefore, carried out a blinded comparison of laparoscopic ultrasound with fluoroscopic operative cholangiography.
  
  
  METHODS
  This study included 135 patients (average age, 53 years) undergoing laparoscopic cholecystectomy with or without bile duct exploration. Laparoscopic ultrasound examination was performed by an experienced surgeon blinded to the patient's clinical condition. This was followed by an operative cholangiogram. Bile ducts were explored if stones were seen, and the patients were followed up.
  
  
  RESULTS
  Laparoscopic ultrasound identified the bile ducts satisfactorily in 131 cases and operative cholangiography in 121 cases. Duct stones were present in 49 cases. They were correctly identified by ultrasound in 47 cases and by cholangiography in 42 cases. There was one false positive cholangiographic examination. The sensitivity was 96% for ultrasound and 86% for cholangiography. The specificities were 100% and 99%, respectively.
  
  
  CONCLUSIONS
  Laparoscopic ultrasound examination of the bile duct is superior to operative cholangiography and could replace it.
authors.affiliation: Department of Surgery, Southmead Hospital, Bristol BS10 5NB, Great Britain.
authors.forename: S E
authors.initials: SE
authors.lastname: Tranter
authors.forename: M H
authors.initials: MH
authors.lastname: Thompson
mesh_terms: D002758:Cholangiography; D017081:Cholecystectomy, Laparoscopic / Q000379:methods*; D003135:Common Bile Duct / Q000000981:diagnostic imaging*; D005260:Female; D042882:Gallstones / Q000175:diagnosis* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D011446:Prospective Studies; D016037:Single-Blind Method; D014463:Ultrasonography