Definition: The structure at the pharyngoesophageal junction consisting chiefly of the CRICOPHARYNGEUS MUSCLE. It normally occludes the lumen of the ESOPHAGUS, except during SWALLOWING.
diseases: coordinate IM with ESOPHAGEAL DISEASES (IM) or specific esophageal disease (IM); neoplasms: coordinate IM with ESOPHAGEAL NEOPLASMS (IM)
See AlsoLaryngopharyngeal Reflux
Other names Sphincter, Upper Esophageal; Upper Esophageal Sphincter
