title: Prospective randomized comparison of laparoscopic ultrasonography using a flexible-tip ultrasound probe and intraoperative dynamic cholangiography during laparoscopic cholecystectomy.
abstract: BACKGROUND
  We performed a prospective randomized comparison of laparoscopic intraoperative ultrasonography (LIOU) and dynamic intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC).
  
  
  METHODS
  LIOU and IOC were attempted in 518 consecutive patients scheduled for laparoscopic cholecystectomy. The order in which the diagnostic procedures were performed was randomly assigned.
  
  
  RESULTS
  LIOU failed in two patients (0.4%), and there were 41 (7.9%) failed IOC. The common bile duct (CBD) was visualized reliably with both methods. Our patients showed sensitivities of 83.3% and 100% and specificities of 100% and 98.9%, with an overall accuracy of 99.2% and 98.9% for LIOU as compared to IOC for identifying unsuspected common bile duct stones. The time necessary for the examination was significantly shorter in LIOU than in IOC (7 versus 16 min).
  
  
  CONCLUSIONS
  LIOU performed by experienced surgeons is a good and effective method to assess the CBD, including the neighboring structures of hepatoduodenal ligament. Using powerful, flexible-tip ultrasound probes, CBD exploration can be done in a longitudinal fashion, which is necessary for good anatomical clarity. A lack of adverse effects, shorter examination times, and lower costs are some of the advantages of this method. The most important advantage is the possibility of unlimited repetition, especially if there is difficulty identifying anatomic structures. In addition, there are some indications that LIOU has the potential to recognize major iatrogenic bile duct injuries.
authors.affiliation: Diakonie-Hospital Rotenburg/Wümme, I. Chirurgische Klinik für Allgemein-, Viszeral-, und Thoraxchirurgie, Rotenburg/Wümme, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Birth
authors.forename: K U
authors.initials: KU
authors.lastname: Ehlers
authors.forename: K
authors.initials: K
authors.lastname: Delinikolas
authors.forename: H F
authors.initials: HF
authors.lastname: Weiser
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002758:Cholangiography / Q000379:methods*; D017081:Cholecystectomy, Laparoscopic / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D042882:Gallstones / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D020706:Laparoscopes; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011897:Random Allocation; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000295:instrumentation* / Q000379:methods