title: [Helical CT compared to ERCP in obstructive biliary pathology].
abstract: BACKGROUND
  Endoscopic retrograde cholangiopancreatography (ERCP) is the examination of choice in the diagnosis of biliary tract pathology although newer, less invasive techniques with high diagnostic sensitivity should be evaluated. The aim of this study was to evaluate the diagnostic efficacy of helical computed tomography (CT) in bile duct obstruction, particularly in choledocholithiasis.
  
  
  METHODS
  Forty-four patients with suspected bile duct obstruction were prospectively evaluated. Helical TC was carried out 12 hours before ERCP and patients were grouped according to risk of choledocholithiasis.
  
  
  RESULTS
  Choledocholithiasis was found in 20 patients (45.4%). Helical TC identified this pathology in 17 and correctly ruled it out in 18 of 24 patients (S: 85%, E: 75%, positive predictive value 74%, negative predictive value 85.7%. Of the patients with choledocholithiasis, bile duct dilatation was found in 18. Helical TC correctly diagnosed this pathology in 16 of the 18 patients (88.8%). Helical TC correctly diagnosed one of two patients (50%) with choledocholithiasis and normal bile ducts.
  
  
  CONCLUSIONS
  Helical TC is effective in the diagnosis of choledocholithiasis but is not sufficiently accurate to be used in the screening of this entity.
authors.affiliation: Sección de Aparato Digestivo, Hospital de León.
authors.forename: J
authors.initials: J
authors.lastname: Espinel
authors.forename: T
authors.initials: T
authors.lastname: Lorenzo
authors.forename: F
authors.initials: F
authors.lastname: Muñoz
authors.forename: S
authors.initials: S
authors.lastname: Costilla
authors.forename: S
authors.initials: S
authors.lastname: Vivas
authors.forename: F
authors.initials: F
authors.lastname: Jorquera
authors.forename: J L
authors.initials: JL
authors.lastname: Olcoz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000379:methods* / Q000706:statistics & numerical data; D002779:Cholestasis / Q000000981:diagnostic imaging*; D005260:Female; D042882:Gallstones / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000706:statistics & numerical data