[A case of lower esophageal muscular ring presenting with dysphagia].

There are diverse ring-like narrowings in the lower esophagus: mucosal ring, muscular ring, ring-like annular peptic stricture. Esophageal muscular ring is extremely rare and generally asymptomatic. It occurs at the proximal border of the esophageal vestibule that corresponds to the upper end of the lower esophageal sphincter. We experienced a case of lower esophageal muscular ring with a symptom of intermittent mild dysphagia for 40 years and report the findings with a review of the literature.