Pharyngeal Pouch

Definition/diagnostic criteria
A pharyngeal pouch is a rare condition characterised by the outpouching of the pharyngeal mucosa through the muscle layers of the pharyngeal wall, creating a pouch or diverticulum. This typically occurs at the junction of the pharynx and the oesophagus. The condition is most commonly diagnosed in older adults, with a peak incidence in the seventh decade of life.

Epidemiology
The precise incidence of pharyngeal pouches in the UK is not well documented. However, it is generally considered to be a rare condition. It predominantly affects older adults and is more common in men than in women.

Diagnosis
Clinical features: Patients with a pharyngeal pouch may present with a range of symptoms, including dysphagia, regurgitation of undigested food, chronic cough, aspiration and weight loss. Some patients may also report a sensation of a lump in the throat or neck and, in some cases, a visible or palpable lump may be present. Halitosis (bad breath) is also a common feature, due to the retention of food in the pouch.

Investigations: The diagnosis of a pharyngeal pouch is typically confirmed through radiological investigations. A barium swallow is the investigation of choice, which can demonstrate the presence, size and anatomical location of the pouch. Endoscopy can also be used to visualise the pouch, although care must be taken to avoid perforating the diverticulum. Typical abnormalities found on investigations include the presence of a sac-like structure arising from the pharyngeal wall, which fills with barium during a swallow study.

Treatment The treatment of pharyngeal pouches depends on the size of the pouch and the severity of symptoms. Small, asymptomatic pouches may require no treatment, whereas larger pouches or those causing significant symptoms may require surgical intervention. The aim of surgery is to divide the cricopharyngeal muscle (which is believed to be dysfunctional in patients with pharyngeal pouches) and to remove or invert the pouch. This can be achieved through an open surgical approach or, increasingly, through endoscopic techniques.

Prognosis The prognosis for patients with a pharyngeal pouch is generally good, especially if the condition is identified and treated promptly. Surgical treatment is associated with good outcomes and a low risk of recurrence. However, as the condition predominantly affects older adults, the overall health and fitness of the patient can impact the prognosis.