title: [Diagnostic performance of biliary ultrasound vs. magnetic resonance cholangiogram in patients with recurrent biliary obstruction.].
abstract: BACKGROUND
  Obstructive jaundice in patients with previous cholecystectomy requires a precise diagnosis. In the diagnostic algorithm, biliary ultrasound (BUS) and magnetic resonance cholangiogram (MRC) are used, although the accuracy of each method is unknown in our setting. No previous comparison of US and MRC in subjects with cholecystectomy has been made.
  
  
  OBJECTIVE
  To determine diagnostic accuracy of BUS and MRC in patients with recurrent biliary obstruction.
  
  
  METHODS
  Patients with endoscopic retrograde cholangiopacreatography (ERCP) demonstrating recurrent biliary obstruction by stones were included. All patients underwent BUS and MRC. We determined the diagnostic performance of each image study compared with ERCP.
  
  
  RESULTS
  Twenty-seven patients with a mean age of 62.9 +/- 17.3 years-old were included. Sensitivity and specificity of BUS were 0.12 and 0.58, respectively. Figures for MRC were 0.88 and 0.82. Diagnostic agreement between ERCP and MRC was k= 0.66 whereas BUS had a k of only 0.26.
  
  
  CONCLUSIONS
  MRC had good diagnostic performance for recurrent choledocolithiasis. BUS demonstrated lower accuracy compared with previous reports, so should not be considered in the initial approach of recurrent choledocus obstruction.
authors.affiliation: Residentes de Medicina Interna.Servicio de Medicina Interna, Hospital Central Sur, PEMEX. drvenicechv@yahoo.com.mx
authors.forename: V
authors.initials: V
authors.lastname: Chávez-Valencia
authors.forename: H F
authors.initials: HF
authors.lastname: Espinosa-Ortega
authors.forename: D
authors.initials: D
authors.lastname: Espinoza-Peralta
authors.forename: C A
authors.initials: CA
authors.lastname: Arce-Salinas
mesh_terms: D002758:Cholangiography / Q000379:methods*; D002779:Cholestasis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014463:Ultrasonography