(See also Overview of Esophageal and Swallowing Disorders Overview of Esophageal and Swallowing Disorders The swallowing apparatus consists of the pharynx, upper esophageal (cricopharyngeal) sphincter, the body of the esophagus, and the lower esophageal sphincter (LES). The upper third of the esophagus... read more .)
Rarely, webs develop in patients with untreated severe iron deficiency anemia Iron Deficiency Anemia Iron deficiency is the most common cause of anemia and usually results from blood loss; malabsorption, such as occurs in celiac disease, is a much less common cause. Symptoms are usually nonspecific... read more 
; they develop even more rarely in patients without anemia. Webs usually occur in the upper esophagus, causing dysphagia Dysphagia Dysphagia is difficulty swallowing. The condition results from impeded transport of liquids, solids, or both from the pharynx to the stomach. Dysphagia should not be confused with globus sensation... read more for solids. They are best diagnosed by barium swallow.
Webs resolve with treatment of the anemia but can be easily ruptured during esophagoscopy.
