title: Clinical impact of dual red imaging in colorectal endoscopic submucosal dissection: a pilot study.
abstract: BACKGROUND
  Dual red imaging (DRI), a novel image-enhanced endoscopic technique, is expected to improve visibility of thin vessels, but no reports of the clinical use of DRI in colorectal endoscopic submucosal dissection (ESD) have been published. We aimed to compare the visibility of vessels, demarcation line between the submucosal and muscle layers after injection of hyaluronate sodium with minute indigo carmine, and fibrosis on DRI with that on white light imaging (WLI). We applied the principle of DRI to the image of the submucosal layer during colorectal ESD as a pilot study.
  
  
  METHODS
  A total of seven physicians compared 17 DRI images to the corresponding WLI images in colorectal ESD. The physicians compared the number of arteries identified on DRI with the actual number of arteries. The physicians rated the visibility of vessels, the demarcation line between the submucosal and muscle layers after injection of hyaluronate sodium with minute indigo carmine, and fibrosis. Inter-observer agreement was also examined using the kappa statistic.
  
  
  RESULTS
  Visibility of vessels and the demarcation line between the submucosal and muscle layers after injection of hyaluronate sodium with minute indigo carmine improved with the use of DRI compared with that using WLI. DRI can discriminate between arteries and veins clearly through the color of the vessels.
  
  
  CONCLUSIONS
  DRI improves the visibility of vessels, especially that of arteries, as they appear orange, and the demarcation line of the muscle layer. DRI may help to make colorectal ESD safer and faster.
authors: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors: Yuki
authors: Y
authors: Ninomiya
authors: Department of Endoscopy, Hiroshima University Hospital, 1-2-3 Kasumi Minamiku, Hiroshima, Japan.
authors: Shiro
authors: S
authors: Oka
authors: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors: Shinji
authors: S
authors: Tanaka
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Daiki
authors: D
authors: Hirano
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Kyoku
authors: K
authors: Sumimoto
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Yuzuru
authors: Y
authors: Tamaru
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Naoki
authors: N
authors: Asayama
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Kenjiro
authors: K
authors: Shigita
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Soki
authors: S
authors: Nishiyama
authors: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors: Nana
authors: N
authors: Hayashi
authors: Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan.
authors: Kazuaki
authors: K
authors: Chayama
keywords: colorectal tumor; dual red imaging; endoscopic submucosal dissection; image-enhanced endoscopy