title: Three-dimensional virtual cholangioscopy: a reliable tool for the diagnosis of common bile duct stones.
abstract: OBJECTIVE
  Our goal was to evaluate the clinical reliability of a new software system employing 3-dimensional (3D) virtual anatomic reconstruction and intraluminal virtual exploration for detection of choledocholithiasis and preoperative visualization of the biliary anatomy.
  
  
  BACKGROUND
  Virtual reality systems have been proposed for gastroscopy, bronchoscopy, and colonoscopy, as well as for the 3D reconstruction of liver anatomy and hepatic lesions. The impact of these systems in preoperative diagnostics has not been established due to the lack of large clinical series evaluating their reliability.
  
  
  METHODS
  From November 2000 to July 2002, all patients presenting to our Institute with suspected choledocholithiasis were prospectively included in the study. All patients underwent conventional magnetic resonance cholangiopancreatography (MRCP) and either intraoperative cholangiogram (IOC) or endoscopic retrograde cholangiopancreatography (ERCP). The digital data from MRCP were incorporated into an original virtual reality software system to generate a 3D reconstruction. All 3D reconstructions were evaluated by a surgeon and a computer software engineer who were blind to the results of the IOC or ERCP. Sensitivity and specificity were then calculated based on the results of either the IOC or ERCP.
  
  
  RESULTS
  Sixty-five patients were enrolled in the study. The average time required to reconstruct the images into navigable virtual reality was 7.5 minutes (range, 4-13.5). The 3D virtual cholangioscopy had sensitivity and specificity rates of 71% and 91%, respectively, compared with 61% and 86% of the standard MRCP.
  
  
  CONCLUSIONS
  : The 3D virtual cholangioscopy provides detailed preoperative reconstruction of biliary anatomy and reliable identification of choledocholithiasis with acceptable sensitivity and specificity in a clinical setting. Newer software developments may further enhance its accuracy, so that virtual cholangioscopy might challenge or replace more invasive diagnostic measures in the near future.
authors.affiliation: IRCAD/European Institute of Telesurgery, Université Louis Pasteur, 1 Place de l'Hopital, 67091 Strasbourg, France.
authors.forename: Michele
authors.initials: M
authors.lastname: Simone
authors.forename: Didier
authors.initials: D
authors.lastname: Mutter
authors.forename: Francesco
authors.initials: F
authors.lastname: Rubino
authors.forename: Erik
authors.initials: E
authors.lastname: Dutson
authors.forename: Catherine
authors.initials: C
authors.lastname: Roy
authors.forename: Luc
authors.initials: L
authors.lastname: Soler
authors.forename: Jacques
authors.initials: J
authors.lastname: Marescaux
mesh_terms: D002758:Cholangiography; D002760:Cholangiopancreatography, Endoscopic Retrograde; D042883:Choledocholithiasis / Q000175:diagnosis* / Q000601:surgery; D003135:Common Bile Duct / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014584:User-Computer Interface