title: Application of computed tomographic colonography in diagnosis of colonic polyps.
abstract: OBJECTIVE
  To assess the clinical values of computed tomographic colonography (CTC) in diagnosis of colonic polyps.
  
  
  METHODS
  Forty-two patients who were clinically suspicious of colonic polyps or underwent colonic polyps screening received examinations with both CTC and conventional colonoscopy. Sixteen- or 64-slice spiral computed tomography and professional imaging processing techniques were used for evaluation. Per-polyp and per-patient results were analyzed. Those by per-polyp were subsequently divided into > or = 10 mm group, 5-10 mm group, and < or =5 mm group. Sensitivity, positive predictive value (PPV), specificity, negative predictive value (NPV), and accuracy were calculated using statistical method for diagnostic studies, with conventional colonoscopy as a gold standard.
  
  
  RESULTS
  Ninety and 61 polyps were found by CTC and conventional colonoscopy, respectively. The per-polyp sensitivity/PPV were 80.3%/55.6% in total, and 100%/92.9%, 93.8%/65.2%, and 68.8%/ 41.5% in the > or = 10 mm group, 5-10 mm group, and < or =5 mm group, respectively. The per-patient sensitivity, PPV, specificity, NPV, and accuracy were 97.1%, 89.5%, 42.9%, 75.0%, and 88.1%, respectively.
  
  
  CONCLUSIONS
  CTC can clearly reveal the morphology of colonic polyps and be used as a routine monitoring method for the clinical diagnosis of polyps.
authors.affiliation: Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China. qinmingwei@hotmail.com
authors.forename: Ming-wei
authors.initials: MW
authors.lastname: Qin
authors.forename: Wei-dong
authors.initials: WD
authors.lastname: Pan
authors.forename: Guan-ning
authors.initials: GN
authors.lastname: Cong
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.forename: Yun-qing
authors.initials: YQ
authors.lastname: Zhang
authors.forename: Ji-xiang
authors.initials: JX
authors.lastname: Liang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D023881:Colonography, Computed Tomographic; D003113:Colonoscopy; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000473:pathology; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity