title: Bladder tumors: dynamic contrast-enhanced axial imaging, multiplanar reformation, three-dimensional reconstruction and virtual cystoscopy using helical CT.
abstract: BACKGROUND
  There have been few studies to evaluate the effects of helical CT on bladder tumor. This study was to evaluate the clinical applications of helical CT dynamic contrast-enhanced axial imaging, multiplanar reformation (MPR), three-dimensional (3D) reconstruction and virtual cystoscopy (CTVC) in bladder tumors.
  
  
  METHODS
  The precontrast and four-phase postcontrast helical CT scans were performed in 42 patients with bladder tumors confirmed by conventional cystoscopy and pathology. MPR, 3D and CTVC images were generated from the volumetric data of the excretory phase. The results were then compared with the findings of conventional cystoscopy and surgery in a double-blinded mode.
  
  
  RESULTS
  The sensitivity of the axial, 3D and CTVC images in detecting the bladder tumors were 90.8%, 76.9% and 95.4% respectively. The dynamic contrast-enhanced axial images could provide excellent intramural and extravesical information, and the accuracy in preoperative tumor staging was 87.7%. MPR could directly demonstrate the origin and extravesical invasions of the tumors and their relation to the ureter. 3D and CTVC images were useful for displaying the surface morphology of the tumor and the relationship between the tumor and the ureteric orifices, whereas CTVC could depict the tumors smaller than 5 mm that were not seen on the axial images.
  
  
  CONCLUSIONS
  The combination of axial, MPR, 3D and CTVC images with helical CT can provide comprehensive information on bladder tumor.
authors.affiliation: Department of Radiology, Air Force General Hospital, Beijing 100036, China. wand65@hotmail.com
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.forename: Wan-shi
authors.initials: WS
authors.lastname: Zhang
authors.forename: Ming-hui
authors.initials: MH
authors.lastname: Xiong
authors.forename: Min
authors.initials: M
authors.lastname: Yu
authors.forename: Jia-xing
authors.initials: JX
authors.lastname: Xu
mesh_terms: D000328:Adult; D000368:Aged; D003558:Cystoscopy; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D036542:Tomography, Spiral Computed / Q000379:methods*; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging*