title: Split-bolus MDCT urography: Upper tract opacification and performance for upper tract tumors in patients with hematuria.
abstract: OBJECTIVE
  Our purpose was to assess upper urinary tract opacification and the performance of split-bolus MDCT urography for upper tract tumors in patients with hematuria.
  
  
  METHODS
  Between January 2004 and December 2006, we identified 200 patients (119 men, 81 women; median age, 58 years, age range, 18-89 years) who underwent MDCT urography for hematuria. MDCT urography included unenhanced and combined nephrographic and excretory phase imaging of the urinary tract. Images were independently reviewed by two radiologists blinded to the final diagnosis. The degree of upper urinary tract opacification and the diagnosis were recorded. Prospective interpretations were also reviewed. The standard of reference included all available clinical, imaging, and laboratory data for up to 12 months after MDCT urography. Sensitivity, specificity, accuracy, and positive and negative predictive values were calculated for upper tract tumors for prospective and retrospective interpretations.
  
  
  RESULTS
  For reviewers 1 and 2, 85.1% and 84.5% of segments were at least 50% opacified, respectively. Final diagnoses for hematuria were no cause, 123 (61.5%); urothelial cancer, 27 (13.5%); nonmalignant, 46 (23%) and indeterminate, four patients (2%). There were nine upper tract cancers. Sensitivity, specificity, and accuracy for upper tract cancers for prospective interpretation, reviewer 1 and reviewer 2, were 100%, 99%, 99%; 100%, 99.5%, 99.5%; and 88.9%, 99.0%, 98.5%, respectively.
  
  
  CONCLUSIONS
  Split-bolus MDCT urography provided at least 50% opacification of the majority of upper urinary tract segments and had high sensitivity, specificity, and accuracy for the detection of upper urinary tract tumors.
authors.affiliation: Joint Department of Medical Imaging, University of Toronto, ON, Canada.
authors.forename: Ekta
authors.initials: E
authors.lastname: Maheshwari
authors.forename: Martin E
authors.initials: ME
authors.lastname: O'Malley
authors.forename: Sangeet
authors.initials: S
authors.lastname: Ghai
authors.forename: Marie
authors.initials: M
authors.lastname: Staunton
authors.forename: Christine
authors.initials: C
authors.lastname: Massey
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D005260:Female; D006417:Hematuria / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014283:Triiodobenzoic Acids; D014567:Urography / Q000379:methods*; D014571:Urologic Neoplasms / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; C044834:iodixanol