squamocolumnar Z line
squamocolumnar Z lineEndoscopy A zig-zag border seen by upper GI endoscopy which corresponds to the abrupt transition from stratified squamous or esophageal epithelium to columnar–gastric epithelium; the Z line's appearance is due to the change from the multicelled layer of the esophagus, to the single cell layer of gastric mucosa in intimate contact with blood vessels. See Barrett's esophagus.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.