Columnar-lined esophagus. Definitions.

Recognition of a columnar-lined esophagus requires precise criteria by which to delimit the esophagus and the stomach. Endoscopically recognizable landmarks such as the squamocolumnar junction (SCJ or Z-line) can be used to identify structures at the gastroesophageal junction. Once the SCJ is located proximal to the gastroesophageal junction, a columnar-lined segment of esophagus is visible. If biopsy specimens from the columnar-lined segment show specialized intestinal metaplasia, then the patient has Barrett's esophagus (BE), and the extent of the columnar lining determines if it is short- or long-segment BE.