Zenker (pharyngoesophageal) diverticulum (ZD)

The diverticular pouch can trap food and medication Patients often regurgitate the undigested food or medications several hours after eating. This can be more pronounced when the individual lies supine, as in this patient. Abnormal spasm or diminished relaxation of the cricopharyngeal muscles during swallowing (cricopharyngeal motor dysfunction) is thought to be the underlying mechanism of ZD formation. Increased intraluminal pressure above the cricopharyngeus muscle eventually results in herniation of the mucosa through an area of weakness Therefore, ZD is classified as a pulsion (resulting from increased intraluminal forces), rather than a traction (resulting from external tugging forces), pseudodiverticulum. Treatment of symptomatic patients involves surgical division of the cricopharyngeus muscle (cricopharyngeal myotomy). The diverticular pouch can be removed or combined with the esophageal lumen.