- A number of distinct types of esophageal diverticula are found clinically with distinct locations, etiologies, and clinical consequences. All are true diverticula and thus are surrounded by all histological layers of the esophageal wall.
- Zenker Diverticuli typically occur just above the Upper Esophageal Sphincter (UES). There is a natural anatomic point of weakness of the esophageal wall just above the UES and congenitally reduced size of this sphincter or dysfunction of adjacent muscles can result in the generation of a diverticulum. Zenker diverticuli tend to present with food regurgitation and, if large, dysphagia.
- Mid-esophageal Diverticulum typically occur somewhere between the UES and the Lower Esophageal Sphincter (LES). Motor dysfunction of the esophageal muscularis propria results in an esophageal segment which cannot conduct peristaltic waves and thus increased pressure and diverticulum-generation above the restriction point. Mid-esophageal Diverticuli tend to be asymptomatic.
- Epiphrenic Diverticuli typically occur just above the LES and are associated with achalasia. Although epiphrenic diverticuli may be clinically silent they can manifest with nocturnal regurgitation of fluid.