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A pharyngeal pouch or Zenker's diverticulum is a pulsion diverticulum that arises between the cricopharyngeus
and thyropharyngeus muscles of the inferior pharyngeal constrictor. Most are seen on the posterior or
posterolateral aspects of the pharynx and are more common on the left side of the neck. Histologically they
consist of stratified squamous epithelium and submucosa and lack a muscle coat. Rarely a squamous cell
carcinoma or carcinoma in-situ may be present within the pouch. The aetiology is unknown but the
principal underlying factor is believed to be a structural or physiological abnormality of the the
cricopharyngeus muscle.
Pouches almost invariably occur in patients over the age of 70 years and are more common in men than
women. Typical symptoms include dysphagia, regurgitation of undigested food, a chronic cough, choking or
aspiration resulting from overspill of food from the pouch. Other symptoms include halitosis, weight
loss and hoarseness. Many of these clinical features may have been present for several months or years
before the diagnosis is made. Clinical examination is often normal . Rarely is a swelling felt in
the neck that gurgles on palpation. Malignancy should be suspected if there is a sudden deterioration in
symptoms.
A pharyngeal pouch can be readily diagnosed on a barium swallow during which the pouch is often well
delineated. Video-fluoroscopy allows monitoring of the swallowing mechanism as a standard barium swallow
may miss a small pouch and may also fail to identify any pharyngeal motility disorder. A filling defect in
the pouch which does not move between images (as a food bolus does) should raise the possibility of a carcinoma
within the pouch.
As pharyngeal pouches usually arise in the elderly, their management is often determined by the general
fitness of the patient and the presence of any co-morbid conditions. The standard treatment is surgical
and this can be achieved by either an external or endoscopic approach. At present there is no consensus as
to which approach is the optimal treatment. External procedures involve a lateral cervical approach,
identifying the pouch and performing a cricopharyngeal myotomy. The pouch can be inverted or excised. Endoscopic
procedures involve the division of the muscular septum between the oesophagus and the pouch (e.g. Dohlman's
procedure) without excising the pouch. The septum can be divided using either electrocautery, laser or an
endoscopic stapling device. Surgery for a pharyngeal pouch, particularly if an external approach is
used, is often associated with a significant risk of complications and peri-operative mortality rates of 2% have
been reported. Complications reported after pharyngeal pouch surgery include recurrent laryngeal nerve
damage, pouch perforation, mediastinitis, pharyngeal fistula, and pharyngeal stenosis.
Recent papers
Hoay C B, Sharp H R, Bates G J. Current practices in pharyngeal pouch surgery in England and Wales. Ann R
Coll Surg Eng 1997; 79: 190-194.
Laing M R, Murthy P, Ah-See K W, Cockburn J S. Surgery for pharyngeal pouch: audit of management with short
and long-term follow up. J R Coll Surg Ed 1995; 40: 315-318.
Siddiq M A, Sood S, Strachan D. Pharyngeal pouch (Zenker's diverticulum). Postgrad
Med J 2001; 77: 506-511.

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