title: Utility of gadolinium-enhanced MR urography in detection of bladder carcinoma.
abstract: OBJECTIVE
  To evaluate the diagnostic accuracy of MR urography (MRU) in detecting bladder carcinoma.
  
  
  METHODS
  A retrospective review of 107 MRU exams obtained to evaluate for possible upper urinary tract urothelial carcinoma from 5/2005 to 5/2009 was performed by two experienced abdominal radiologists. Interpretation of the presence or absence of bladder carcinoma and lesion conspicuity in each imaging phase was made using 5-point confidence grading scales. Exams included 3D T1-weighted spoiled gradient-recalled echo images through the kidneys, ureters and bladder in the coronal plane during parenchymal phases and in both coronal and axial planes during pyelographic phases after intravenous administration of gadolinium and furosemide. Standard of reference was cystoscopy or cystectomy within 30 days of MRU. Statistical measures of performance, including receiver operating characteristics area under the curve (Az) values were calculated.
  
  
  RESULTS
  Bladder carcinoma was present in 26/107 patients (24%). Sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Az value were 73.1%, 91.4%, 86.9%, 73.1%, 91.4%, 0.89 for the first reviewer, and 84.6%, 75.3%, 77.6%, 52.4%, 93.8%, 0.86 for the second. Lesion conspicuity was superior on the parenchymal phase compared to the pyelographic phase (p=0.04).
  
  
  CONCLUSIONS
  MRU obtained for suspicion of upper urinary tract TCC has a moderate accuracy in detecting bladder carcinoma.
authors.affiliation: Department of Radiology, Mayo Clinic, W2 Radiology, 200 1st St SW, Rochester, MN 55905, United States.
authors.forename: Blake D
authors.initials: BD
authors.lastname: Niederhauser
authors.forename: Akira
authors.initials: A
authors.lastname: Kawashima
authors.forename: Bernard F
authors.initials: BF
authors.lastname: King
authors.forename: Naoki
authors.initials: N
authors.lastname: Takahashi
mesh_terms: D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives*; D008875:Middle Aged; D009942:Organometallic Compounds; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D001749:Urinary Bladder Neoplasms / Q000473:pathology*; D014567:Urography / Q000379:methods
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine