The normal anatomy around the oesophagogastric junction: an endoscopic view.

Where the oesophagus ends and the stomach begins has been a bone of contention for decades between the histologist, physiologist, gastroenterologist, radiologist and surgeon. The oesophagogastric junction (OGJ) is an important anatomical region because of its essential functions in relation to swallowing and as a site of structural defects, inflammation, metaplasia and neoplasia. The location of the diaphragmatic hiatus in relation to the distal oesophagus, the level of the squamocolumnar mucosal junction (SCJ), the location of the distal margin of the mucosal palisade veins and the proximal margin of the gastric mucosal folds are features that permit an accurate endoscopic diagnosis of hiatal hernia and reflux sequelae, including even a minimal extent for Barrett's oesophagus. The physiological OGJ region can be considered to be between the rosette of the lower oesophageal sphincter (LOS) and the angle of His. The most reliable benchmarks for the precise mural OGJ that can be identified during endoscopy are the levels of the cephalad margins of the linear gastric mucosal folds, viewed with the lumen deflated as much as possible, that are juxtaposed to the level of the caudad extent of the oesophageal mucosal palisade veins.