Endoscopic Diagnostic Criteria for Reflux Esophagitis: Endoscopic diagnostic criteria for esophagitis currently use the LA classification criteria. What are LA classification criteria: In 1994, the World Congress of Gastroenterology was held in Los Angeles, USA, where the endoscopic classification of esophagitis was discussed in depth and finally classified as A, B, C, and D. The LA classification criteria were called Los Angeles (LA), or LA classification criteria. The LA classification is currently the most widely used scheme internationally. Grade A: mucosal rupture on the surface of the mucosal fold, but the diameter of the rupture is <5mm; Grade B: mucosal rupture on the surface of the mucosal fold is >5mm in diameter, but there is no fusion between the ruptures; Grade C: mucosal ruptures fuse with each other. Grade D: mucosal breaks fused with each other and involved at least 75% of the four walls of the esophagus. The presence or absence of esophageal strictures, esophageal ulcers and Barrett’s esophagus are also described. The chart below shows grade A, B, C and D from left to right. The chart below shows the following: .