CLOSING MECHANISM OF LOWER ESOPHAGUS IN MAN

Abstract
• The sphincteral structures at the esophagogastric junction were studied radiologically, with the oil contrast technique, in 500 patients. The line marking the boundary between the squamous epithelium of the esophagus and the glandular epithelium of the cardiac portion of the stomach, when seen, presented a typical picture. It was not fixed, however, and was capable of considerable change of position with respect to the level of the diaphragm. The lower esophageal sphincter being identified, the phrenic ampulla and the gastroesophageal vestibule were readily defined above and below it respectively. No evidence of a pinchcock action of the diaphragm on the esophagus was noted. Change in angulation of the esophagus and the stomach played an insignificant part in closing the lower esophagus. The lower esophageal sphincter and the constrictor cardiae are the key structures in the closing mechanism of the lower esophagus.