inferior esophageal sphincter

in·fe·ri·or e·soph·a·ge·al sphinc·ter

a physiologic sphincter at the level of the esophagogastric junction; this is in fact an extrinsic sphincter formed by the surrounding musculature of the esophageal hiatus of the right crus of the diaphragm; causes a normally occurring constriction at the esophagogastric junction observable with a barium swallow.
Full browser ?