title: A novel videoendoscopy system by using autofluorescence and reflectance imaging for diagnosis of esophagogastric cancers.
abstract: BACKGROUND
  Image quality of the prior autofluorescence (AF) imaging systems, including the fiber-optic endoscope, was not feasible for general clinical use. The use of AF image alone resulted in low specificity. The objective of the study was to evaluate the resolution and the sensitivity of the novel videoendoscopy system by using AF and reflectance imaging (AFI) in the diagnosis of early esophagogastric cancers.
  
  
  METHODS
  This was a case series study. The setting was a pretreatment examination at a cancer center. Five patients with superficial esophageal cancers (SEC) and 21 patients with 22 early gastric cancers (EGC) were included in the study. The extent of the tumors was diagnosed by white light (WL), AF and chromoendoscopic observations. The main outcome measurement was the diagnostic accuracy of each observation in relation to the histologic mapping as a criterion standard.
  
  
  RESULTS
  Two of 5 SECs (40%) were correctly diagnosed in the WL image and all (100%) in the AF image as purple or magenta color in a green background. EGCs in atrophic mucosa were observed as purple or magenta areas in a green background, while diffuse-type EGCs in fundic mucosa were observed as green areas in a purple background. Of the 22 EGCs, diagnostic accuracy of WL, AF, and chromoendoscopic observations were 36%: 95% CI [16%, 56%], 68%: 95% CI [49%, 88%], and 91%: 95% CI [79%, 100%], respectively. AFI could reveal flat or isochromatic extensions that were not detected in the WL images. The limitations of the study were ulcerations or inflammation that caused overdiagnosis in the AF observation.
  
  
  CONCLUSIONS
  The resolution of the AFI at present is limited, but the image quality was acceptable. The current system of AFI does not equal to chromoendoscopy in sensitivity but has an advantage over standard WL videoendoscopy.
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Noriya
authors.initials: N
authors.lastname: Uedo
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iishi
authors.forename: Masaharu
authors.initials: M
authors.lastname: Tatsuta
authors.forename: Takuya
authors.initials: T
authors.lastname: Yamada
authors.forename: Hideharu
authors.initials: H
authors.lastname: Ogiyama
authors.forename: Kazuho
authors.initials: K
authors.lastname: Imanaka
authors.forename: Naotoshi
authors.initials: N
authors.lastname: Sugimoto
authors.forename: Koji
authors.initials: K
authors.lastname: Higashino
authors.forename: Ryu
authors.initials: R
authors.lastname: Ishihara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Narahara
authors.forename: Shingo
authors.initials: S
authors.lastname: Ishiguro
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020776:Endoscopes, Gastrointestinal; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D004938:Esophageal Neoplasms / Q000473:pathology*; D005260:Female; D005336:Fiber Optic Technology; D005453:Fluorescence; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D008875:Middle Aged; D055100:Optical Fibers; D015203:Reproducibility of Results; D013274:Stomach Neoplasms / Q000473:pathology*; D014741:Video Recording / Q000295:instrumentation*