title: Dual red imaging (novel advanced endoscopy) can increase visibility and can predict the depth in diagnosing esophageal varices.
abstract: BACKGROUND
  Dual red imaging (DRI) is a new technology that can increase the visibility of deeper veins compared with narrow band imaging (NBI). As esophageal varices (EVs) are a vascular disease occurring in the submucosal layer, their visibility might be increased by DRI. We prospectively clarified whether the visibility of EVs with red color sign (RCS) can be increased by DRI, and clarified the relation between the visibility scores and the obtained endoscopic ultrasound (EUS) images.
  
  
  METHODS
  Forty patients were enrolled. The visibility of the EVs on DRI and NBI endoscopic images was evaluated by five observers in a blinded manner and was compared with a white light image (bad, 0; equal, 1; good, 2). The diameter of the lumen and the depth of the EVs and RCS from the epithelium were measured by EUS. The relation between the visibility scores and the EUS findings was investigated.
  
  
  RESULTS
  The DRI scores were 1.66 ± 0.34 for the EV substance and 1.79 ± 0.28 for the RCS, whereas the NBI scores were 0.68 ± 0.38 and 0.41 ± 0.28, respectively. A significant negative correlation was found between the depth and the visibility score (r = -0.505, p = 0.001 for EVs; r = -0.458, p = 0.003 for RCS).
  
  
  CONCLUSIONS
  DRI increased the visibility of the EVs and RCS. The visibility of the EVs or RCS in the shallower position was more enhanced by DRI. Visual recognition of the changing degrees of visibility by DRI enables the prediction of the depth of EVs.
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan. furuich@tokyo-med.ac.jp.
authors: Yoshihiro
authors: Y
authors: Furuichi
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Takuji
authors: T
authors: Gotoda
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Fuminori
authors: F
authors: Moriyasu
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Saori
authors: S
authors: Ogawa
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Yoshitaka
authors: Y
authors: Kasai
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Hirohito
authors: H
authors: Takeuchi
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Yuu
authors: Y
authors: Yoshimasu
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Takatomo
authors: T
authors: Sano
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Katsutoshi
authors: K
authors: Sugimoto
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Takashi
authors: T
authors: Kawai
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Yoshiyuki
authors: Y
authors: Kobayashi
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Ikuo
authors: I
authors: Nakamura
authors: Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
authors: Takao
authors: T
authors: Itoi
mesh_terms: D000368:Aged; D019160:Endosonography / Q000295:instrumentation / Q000379:methods; D004932:Esophageal and Gastric Varices / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D004945:Esophagoscopy / Q000295:instrumentation / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D062048:Narrow Band Imaging / Q000295:instrumentation / Q000379:methods; D011446:Prospective Studies; D016037:Single-Blind Method
keywords: Dual red imaging; Endoscopic ultrasonography; Esophageal varices; Narrow band imaging; Red color sign; Visibility