Supplementary Material for: Utility of Dual Red Imaging for Endoscopic Hemostasis of Gastric Ulcer Bleeding

Dual red imaging (DRI; Red Dichromatic Imaging (RDI)) is a new type of image-enhanced endoscopy composed of two long wavelengths that together can visualize vessels in the deep submucosa of the gastrointestinal wall. We treated a case of gastric ulcer bleeding in which the bleeding point could be clearly visualized using DRI. A 71-year-old man who was taking warfarin for atrial fibrillation noticed tarry stool, entered a state of hypovolemic shock, and underwent emergency esophagogastroduodenoscopy. The procedure was performed with a GIF-Y0058 prototype endoscope (Olympus Co., Tokyo, Japan) equipped with a DRI mode. An ulcer with active bleeding was found in the upper portion of the stomach, but the massive volume of the bleeding made it difficult to identify the bleeding point using white light imaging (WLI). Upon switching to DRI mode by pushing a button on the endoscope, the bleeding point could be identified rapidly and precisely, as it appeared in a deeper yellow than the surrounding area. Complete hemostasis was thereupon achieved. This case demonstrates that the DRI mode may be useful for detecting bleeding points that are difficult to detect using WLI.