title: Biliary dilatation: differentiation of benign from malignant causes--value of adding conventional MR imaging to MR cholangiopancreatography.
abstract: OBJECTIVE
  To determine the value of conventional T1 - and T2-weighted images and gadolinium-enhanced dynamic magnetic resonance (MR) images as a supplement to MR cholangiopancreatographic (MRCP) images in differentiation of benign from malignant causes of biliary dilatation.
  
  
  METHODS
  MR studies in 62 patients with biliary dilatation with proved causes included conventional T1- and less heavily T2-weighted images, as well as gadolinium-enhanced dynamic images and heavily T2-weighted MRCP images. Two radiologists reviewed MRCP images alone, MRCP images with nonenhanced T1 - and T2-weighted MR images, and MRCP images with nonenhanced and gadolinium-enhanced dynamic images.
  
  
  RESULTS
  For differentiation of benign from malignant causes of biliary dilatation, the area under the receiver operating characteristic curve (A(z)) was significantly (P < .05) larger for MRCP images interpreted with T1 - and T2-weighted images (0.9547 for reader 1, 0.8404 for reader 2) than for MRCP images alone (0.8144 for reader 1, 0.8122 for reader 2). The addition of gadolinium-enhanced dynamic MR images to MRCP images with nonenhanced T1- and T2-weighted images did not significantly increase accuracy (A(z) = 0.9554 for reader 1 and 0.8650 for reader 2), but the level of confidence was increased in 17%-24% of cases.
  
  
  CONCLUSIONS
  Use of nonenhanced T1- and less heavily T2-weighted images with MRCP images significantly improved the diagnostic accuracy of MR examinations of pancreaticobiliary disease.
authors.affiliation: Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA 19107-5244, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kim
authors.forename: D G
authors.initials: DG
authors.lastname: Mitchell
authors.forename: K
authors.initials: K
authors.lastname: Ito
authors.forename: E K
authors.initials: EK
authors.lastname: Outwater
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000175:diagnosis*; D017734:Bile Ducts, Extrahepatic / Q000473:pathology; D001651:Cholestasis, Extrahepatic / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests