title: Evaluation of the effectiveness of color intensity analysis using a second-generation autofluorescence imaging system for diminutive colorectal polyp differentiation.
abstract: OBJECTIVE
  We previously reported the effectiveness of color tone intensity analysis using autofluorescence imaging (AFI) for distinguishing between colorectal neoplastic and non-neoplastic lesions. Moreover, a second-generation AFI system has become commercially available in Japan. In the present study, we assessed the effectiveness of color tone intensity analysis using a second-generation AFI system for evaluating diminutive colorectal lesions.
  
  
  METHODS
  We retrospectively reviewed the cases of 35 consecutive patients with 101 diminutive colorectal lesions that were examined using a second-generation AFI system and resected at the Jikei University Hospital. We estimated the mean green-to-red (G/R) ratio - obtained by dividing the green color tone intensity by the red color tone intensity - of the lesions and compared the values of the neoplastic and non-neoplastic lesions. We also assessed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the AFI system for neoplastic lesion identification.
  
  
  RESULTS
  The mean G/R ratios of the non-neoplastic and neoplastic lesions were 1.06 and 0.87, respectively; the mean G/R ratio significantly differed between the neoplastic and non-neoplastic lesions. Using the second-generation AFI system, neoplastic lesions were identified with a sensitivity, specificity, PPV, and NPV of 94.2%, 91.8%, 92.5%, and 93.8%, respectively.
  
  
  CONCLUSIONS
  Color intensity analysis of diminutive colorectal polyps using the second generation AFI system could effectively distinguish between neoplastic and non-neoplastic lesions.
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Tamai
authors.forename: Syoichi
authors.initials: S
authors.lastname: Saito
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Aihara
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kato
authors.forename: Hisao
authors.initials: H
authors.lastname: Tajiri
mesh_terms: D015331:Cohort Studies; D003111:Colonic Polyps / Q000473:pathology* / Q000601:surgery; D003113:Colonoscopy / Q000379:methods*; D003116:Color; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007564:Japan; D008297:Male; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D061848:Optical Imaging / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
keywords: autofluorescence imaging; colonoscopy; colorectal cancer; diminutive; polyp