It s located at the dorsoesophageal wall and is a pseudodiverticula, because it s formed only by mucosa and submucosa. Neurologic coordination disorders of the upper esophagus and anatomical aspects are being discussed as causative. Symptoms at first are a mere global sensation. Progression is frequent and leads to esophageal compression and dysphagia. Large diverticula can retain food giving rise to the development of a bezoar.
Retained food can also result in regurgitation, thus facilitating aspiration.
The right picture shows a Zenker s diverticula with a bezoar. The endoscopist is always in danger of causing a diverticular perforation when inserting the endoscope resulting in a life threatening mediastinitis. Apart from the Zenker s diverticula at the upper entrance of the esophagus, which is of course a pseudodiverticula, there is a second kind called thoracal diverticula. All those are true diverticula formed by all anatomical layers of the esophageal wall. Causes might be motility disorders, inflammatory changes or genetic abnormalities.