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In anatomy, Zenker's diverticulum, also pharyngoesophageal diverticulum, also pharyngeal pouch, also hypopharyngeal diverticulum, is a diverticulum of the mucosa of the pharynx, just above the cricopharyngeal muscle (i.e. above the upper sphincter of the esophagus). It is a false diverticulum (not involving all layers of the esophageal wall).
Zenker's diverticulum mainly affects older adults.
Mechanisms and manifestations
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 (known as Killian's triangle, located superior to the cricopharyngeus muscle and inferior to the inferior constrictor muscles). The result is an outpouching of the posterior pharyngeal wall, just above the esophagus, specifically just above the cricopharyngeal muscle.
While it may be asymptomatic, Zenker diverticulum often causes clinical manifestations such as dysphagia (difficulty swallowing), and sense of a lump in the neck; moreover, it may fill up with food, causing regurgitation (reappearance of ingested food in the mouth), cough (as some food may be regurgitated into the airways), halitosis (smelly breath, as stagnant food is digested by microorganisms), potential infection of the pharyngeal areas due to food stuck, and involuntary gurgling noises when swallowing. 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 (located inferior to the cricopharyngeus on both sides of this muscle's insertion into the cricoid cartilage). Laimer's diverticulum is formed in Laimer's triangle (located inferior to the cricopharyngeus in the posterior midline above the confluence of the longitudinal layer of esophageal muscle). Laimer's triangle is covered only by the circular layer of esophageal muscle.
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 (as they allow for much faster recovery), and the currently preferred treatment is endoscopic stapling (i.e. diverticulotomy with staples ). 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.
- synd/2461 at Who Named It?
- F. A. Zenker and Hugo Wilhelm von Ziemssen. Krankheiten des Oesophagus. Leipzig, 1867.
- van Overbeek JJ (July 2003). "Pathogenesis and methods of treatment of Zenker's diverticulum". Ann. Otol. Rhinol. Laryngol. 112 (7): 583–93. PMID 12903677.
- Sen P, Bhattacharyya AK (August 2004). "Endoscopic stapling of pharyngeal pouch". J Laryngol Otol 118 (8): 601–6. doi:10.1258/0022215041917817. PMID 15453934.
- Chang CY, Payyapilli RJ, Scher RL (June 2003). "Endoscopic staple diverticulostomy for Zenker's diverticulum: review of literature and experience in 159 consecutive cases". Laryngoscope 113 (6): 957–65. doi:10.1097/00005537-200306000-00009. PMID 12782805.
- Altman JI, Genden EM, Moche J (May 2005). "Fiberoptic endoscopic-assisted diverticulotomy: a novel technique for the management of Zenker's diverticulum". Ann. Otol. Rhinol. Laryngol. 114 (5): 347–51. PMID 15966520.
- Miller FR, Bartley J, Otto RA (September 2006). "The endoscopic management of Zenker diverticulum: CO2 laser versus endoscopic stapling". Laryngoscope 116 (9): 1608–11. doi:10.1097/01.mlg.0000233508.06499.41. PMID 16954989.