title: Detection of bladder cancer: comparison of low-dose scans with AIDR 3D and routine-dose scans with FBP on the excretory phase in CT urography.
abstract: OBJECTIVE
  To prospectively compare the detection of bladder cancer between low-dose scans with adaptive iterative dose reduction three dimensional projection (AIDR 3D) and routine-dose scans with filtered back projection (FBP) on the excretory phase (EP) in CT urography.
  
  
  METHODS
  42 patients were included. Routine- and low-dose EP were performed in each patient. Routine-dose images were reconstructed with FBP, and low-dose images were reconstructed with AIDR 3D. Two radiologists scored confidence levels for the presence or absence of bladder cancer using a 5-point scale. The CT dose index of each EP was measured, and the dose reduction was calculated.
  
  
  RESULTS
  Sensitivity, specificity and accuracy were 86.4%, 95.0% and 90.5% on routine-dose scans and were 86.4%, 90.0% and 88.1% on low-dose scans, respectively. There was no significant difference (p; not significant, 1.00 and 1.00, respectively). The average CT dose index was 8.07 and 2.63 mGy on routine- and low-dose scans, and the ratio of dose reduction was 67.6%.
  
  
  CONCLUSIONS
  The detection of bladder cancer on low-dose scans with AIDR 3D is almost equal to that on routine-dose scans with FBP on the EP, with nearly 70% dose reduction.
  
  
  CONCLUSIONS
  Using AIDR 3D, the radiation dose may be reduced on the EP in CT urography for the detection of bladder cancer.
authors.affiliation: 1 Department of Radiology, Osaka Medical College, Takatsuki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Juri
authors.affiliation: 2 Department of Radiology, Osaka University School of Medicine, Suita, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tsuboyama
authors.affiliation: 3 Department of Radiology, Kinki University School of Medicine, Osaka-Sayama, Japan.
authors.forename: Seishi
authors.initials: S
authors.lastname: Kumano
authors.affiliation: 1 Department of Radiology, Osaka Medical College, Takatsuki, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Inada
authors.affiliation: 1 Department of Radiology, Osaka Medical College, Takatsuki, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Koyama
authors.affiliation: 4 Department of Urology, Osaka Medical College, Takatsuki, Japan.
authors.forename: Haruhito
authors.initials: H
authors.lastname: Azuma
authors.affiliation: 1 Department of Radiology, Osaka Medical College, Takatsuki, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Narumi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007472:Iohexol; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D014567:Urography / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol