Clinical applicability of gastroscopy with narrow-band imaging for the diagnosis of Helicobacter pylori gastritis, precancerous gastric lesion, and neoplasia

Figure 6 Narrow-band imaging endoscopy for determining the horizontal margin of gastric dysplasia before endoscopic submucosal dissection. A: Conventional chromoendoscopy using indigo carmine is useful for determining the horizontal margin of gastric neoplasia. However, this procedure requires a dye solution and is time-consuming; B: When the endoscopist presses the button, narrow-band imaging (NBI) endoscopy can be easily performed as a virtual chromoendoscopy. The tumor margin is evident between the large brownish lesion and greenish background mucosa (dotted white line); C: An en bloc-resected specimen by endoscopic submucosal dissection. The orange-colored area indicates a tubulovillous adenoma of 46 mm × 36 mm size, corresponding to the tumor extent determined by NBI endoscopy.