Esophageal rings and webs are folds that block your esophagus either partially or completely. Rings are bands of normal esophageal tissue that form constrictions around the inside of the esophagus. They occur in the lower esophagus. Webs, which arise in the upper esophagus, are thin layers of cells that grow across the inside of the esophagus. Either condition may make it difficult to swallow solid food.
Experts aren't sure what causes esophageal rings and webs. The condition may be congenital (inherited) or may develop after birth. People with esophageal rings and webs commonly have reflux symptoms. When esophageal webs occur together with iron deficiency anemia the condition is known as Plummer-Vinson syndrome.