title: Preoperative diagnosis of bile duct strictures--comparison of intraductal ultrasonography with conventional endosonography.
abstract: BACKGROUND
  The accuracy of intraductal ultrasonography (IDUS) and endoscopic ultrasonography (EUS) were compared in diagnosing biliary obstruction and in predicting surgical resectability.
  
  
  METHODS
  Fifty-six patients with biliary obstruction were investigated preoperatively with both conventional EUS and IDUS. The ultrasonographic miniprobe was inserted into the bile duct system through the working channel of the duodenoscope during endoscopic retrograde cholangiopancreatography (ERCP). Conventional endosonography was performed with echoendoscopes in a standard technique. Images of endoluminal ultrasonography were prospectively reviewed and compared with intraoperative findings and resection specimen analyses.
  
  
  RESULTS
  IDUS exceeded EUS in terms of accuracy (IDUS, 89.1%; EUS, 75.6%; P < 0.002), sensitivity (IDUS, 91.1%; EUS, 75.7%; P < 0.002), specificity (IDUS, 80%; EUS, 75%; NS), and T-staging (IDUS, 77.7%; EUS, 54.1%; P < 0.001). In bile duct carcinomas the accuracy rate for lymph node staging using IDUS (60%) is comparable with that using EUS (62.5%). In pancreatic carcinomas, however, lymph node staging using IDUS (13.3%) is significantly (P < 0.002) inferior to EUS (69.2%). Endoluminal ultrasonography may predict the potential resectability of bile duct tumors (IDUS, 81.8%; EUS, 75.6%; P < 0.002).
  
  
  CONCLUSIONS
  IDUS proved to be accurate in preoperative diagnosing and T-staging of malignant biliary strictures, whereas it is not suitable for lymph node staging. IDUS using miniprobes during ERCP exceeds conventional EUS in terms of depiction of bile duct obstruction, diagnostic accuracy, and sensitivity and in the prediction of surgical tumor resectability. Additionally, different to EUS, IDUS can conveniently be performed during ERCP in one and the same session.
authors.affiliation: Dept. of Medicine B, University of Münster, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Menzel
authors.forename: C
authors.initials: C
authors.lastname: Poremba
authors.forename: K H
authors.initials: KH
authors.lastname: Dietl
authors.forename: W
authors.initials: W
authors.lastname: Domschke
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery; D001652:Bile Ducts / Q000000981:diagnostic imaging*; D002760:Cholangiopancreatography, Endoscopic Retrograde; D002779:Cholestasis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D019160:Endosonography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity