Definition: The physiologic or functional barrier to GASTROESOPHAGEAL REFLUX at the esophagogastric junction. Sphincteric muscles remain tonically contracted during the resting state and form the high-pressure zone separating the lumen of the ESOPHAGUS from that of the STOMACH. (Haubrich et al, Bockus Gastroenterology, 5th ed., pp399, 415)
diseases: coordinate IM with ESOPHAGEAL DISEASES (IM) or specific esophageal disease (IM); neoplasms: coordinate IM with STOMACH NEOPLASMS (IM) or ESOPHAGEAL NEOPLASMS (IM) depending on text
See AlsoGastroesophageal Reflux
Other names Sphincter, Lower Esophageal; Lower Esophageal Sphincter