title: Image quality of a novel light-emitting diode (LED)-illuminated colonoscope.
abstract: OBJECTIVE
  Light-emitting diodes (LEDs) are used widely for their high luminous efficiency and durability. We developed a novel prototype high definition endoscope with white LEDs and evaluated the image quality it produced against a commercial endoscope with conventional light source.
  
  
  METHODS
  The specifications of both colonoscopes were identical, except for the LED light source at the tip of the prototype. We examined 20 patients with rectal or sigmoid colon lesions and the image quality was evaluated in 40 images (one image from the LED colonoscope and one from the conventional colonoscope for each lesion) by three endoscopists. We additionally evaluated the 17 videos recorded with the LED colonoscope that were available. Image quality, mucosal and vascular color, and luminous distribution and intensity were scored on a 5-point scale.
  
  
  RESULTS
  The mean score for vascular color given by one evaluator was significantly higher using the LED colonoscope than using the conventional colonoscope. The mean scores for mucosal color and luminous intensity from another evaluator were significantly lower with the LED colonoscope than with the conventional colonoscope. There were no significant differences in the luminous distribution scores for any of the evaluators. The image quality of the videos was evaluated as being similar with both colonoscopes.
  
  
  CONCLUSIONS
  Image quality from the LED and conventional colonoscopes were similar, although the luminous intensity of the LEDs is inferior to that of the conventional light source at the present time.
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Sasaki
authors.affiliation: Department of Laboratory Science, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Nishikawa
authors.affiliation: Department of Clinical Research, National Hospital Organization Kanmon Medical Center, Shimonoseki, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Yanai
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Munetaka
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Nishimura
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Goto
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Shu
authors.initials: S
authors.lastname: Kiyotoki
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Saito
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Kouichi
authors.initials: K
authors.lastname: Hamabe
authors.affiliation: Department of Gastroenterology, Hayashi Hospital, Yamaguchi, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Tanabe
authors.affiliation: Department of Gastroenterology, Yamaguchi Rosai Hospital, Sanyo-Onoda, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: Department of Gastroenterology, Sanyo-Onoda City Hospital, Sanyo-Onoda, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tokiyama
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Hashimoto
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Okamoto
authors.affiliation: Department of Gastroenterology, St. Hill Hospital, Ube, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Higaki
authors.affiliation: Department of Electrical and Electronic Engineering, Faculty of Engineering, Yamaguchi University, Ube, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kurai
authors.affiliation: Department of Biomolecular Engineering Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ogihara
authors.affiliation: Department of Biomolecular Engineering Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Hamamoto
authors.affiliation: Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Sakaida
mesh_terms: D000368:Aged; D012809:Colon, Sigmoid / Q000000981:diagnostic imaging*; D020685:Colonoscopes; D003113:Colonoscopy / Q000295:instrumentation / Q000379:methods; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D004867:Equipment Design; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation / Q000379:methods; D007564:Japan; D008027:Light; D008297:Male; D012007:Rectum / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D014741:Video Recording