Zenker's diverticulum


A Zenker's diverticulum, also pharyngeal pouch, is a diverticulum of the mucosa of the human pharynx, just above the cricopharyngeal muscle. It is a pseudo diverticulum.
It was named in 1877 after German pathologist Friedrich Albert von Zenker.

Signs and symptoms

In simple words, when there is excessive pressure within the lower pharynx, the weakest portion of the pharyngeal wall balloons out, forming a diverticulum which may reach several centimetres in diameter.
More precisely, while traction and pulsion mechanisms have long been deemed the main factors promoting development of a Zenker's diverticulum, current consensus considers occlusive mechanisms to be most important: uncoordinated swallowing, impaired relaxation and spasm of the cricopharyngeus muscle lead to an increase in pressure within the distal pharynx, so that its wall herniates through the point of least resistance. The result is an outpouching of the posterior pharyngeal wall, just above the esophagus.
While it may be asymptomatic, Zenker diverticulum can present with the following symptoms:
It rarely, if ever, causes any pain.
Cervical webs are seen associated in 50% of patients with this condition.
Rarer forms of cervical esophageal diverticula are the Killian's diverticulum and the Laimer's diverticulum. Killian's diverticulum is formed in the Killian-Jamiseon triangle. Laimer's diverticulum is formed in Laimer's triangle. Laimer's triangle is covered only by the circular layer of esophageal muscle.

Diagnosis

A combination of the simple barium swallow and a thorough endoscopy will normally confirm the diverticulum.

Treatment

If small and asymptomatic, no treatment is necessary. Larger, symptomatic cases of Zenker's diverticulum have been traditionally treated by neck surgery to resect the diverticulum and incise the cricopharyngeus muscle. However, in recent times non-surgical endoscopic techniques have gained more importance, and the currently preferred treatment is endoscopic stapling. This may be performed through a diverticuloscope. Other methods include fibreoptic diverticular repair.
Other non-surgical treatment modalities also exist, such as endoscopic laser, which recent evidence suggests is less effective than stapling.

Epidemiology

Zenker's diverticulum mainly affects older adults. It has an incidence of 2 per 100,000 per year in the UK, but there is significant geographical variation around the world.