The newly developed linked color imaging (LCI) system (FUJIFILM Co.) creates clear and bright endoscopic images by using short-wavelength narrow-band laser light combined with white laser light on the basis of BLI technology. This system can obtain bright endoscopic images even at a distant view because LCI has more intense white light than the short-wavelength narrow-band laser light. Short-wavelength narrow-band laser light enhances the vessels on the mucosal surface and the patterns of the mucosa. Therefore, LCI may facilitate the detection of gastric mucosal lesions. Further studies are needed to confirm the clinical utility of LCI.

LCI enhances differences in hue, in the red region of the spectrum, through digital processing. This makes red areas appear redder and white areas appear whiter. Thus, it is easier to recognize a slight difference in color of the mucosa. Based on previous experience, a new LCI based endoscopic diagnosis criteria called CMV (color- microstructure-vessel) criteria has been proposed, which could be used for judging the gastric mucosal lesions. LCI has the advantage of detecting color changes of the mucosa, and this could provide very valuable and useful evidence for making endoscopic diagnosis. In this study, a blinded random controlled clinical trial is designed to further validate the diagnostic value of LCI based CMV criteria for gastric diseases.

Inclusion Criteria:

• Above 18 years old patients
• Who agree to participate in the study
• Patients with the indications for gastroduodenoscopy

Exclusion Criteria:

• Patients, who were receiving nonsteroidal anti-inflammatory drugs, pump inhibitors (PPI) or antibiotics in the last 3 weeks.
• Severe uncontrolled coagulopathy
• Prior history of gastric surgery.
• Pregnancy and lactation