Summary

The exact definition of dysphagia varies, but, in brief, dysphagia is difficulty with the act of swallowing. Dysphagia may be subjective or objective and can refer to difficulty swallowing solids or liquids. The symptoms may involve anatomical regions from the mouth, to the pharynx, and through the oesophagus. Dysphagia can refer to the sensation of not being able to swallow, food 'sticking' or not passing, choking episodes, or aspiration of food and/or liquids.

Dysphagia is reported to occur in 8% to 10% of the general population over the age of 50 years. [1] However, rates as high as 30% to 40% may be found in patients residing in homes for the aged. [2] [3] Dysphagia can be caused by functional or structural abnormalities of the oral cavity, pharynx, oesophagus, or gastric cardia. [4] It should be distinguished from odynophagia (pain on swallowing) and globus sensation (sensation of a lump in the throat between meals).

Dysphagia may be treated by various specialties or ideally by a multi-specialty team. The core of such a team involves the patient’s primary care physician, otolaryngologists, speech and swallowing therapists, gastroenterologists, and radiologists. In addition, neurologists, dieticians, oncologists, general surgeons, and thoracic surgeons are often involved in the patient’s care.

Swallowing and thus difficulty swallowing can be anatomically and physiologically divided easily into 3 distinct parts: the oral phase, the pharyngeal phase, and the oesophageal phase.

• The oral phase (sometimes referred to as the preparatory phase) is the voluntary phase that occurs in the oral cavity. Mastication with salivary lubrication and tongue movement prepares the bolus to be thrust posteriorly into the pharynx.

• The pharyngeal phase involuntarily transfers the bolus of food and/or liquid from the mouth to the oesophagus. Its coordinated contractions not only are necessary to propel the bolus but are crucial in protecting the larynx and upper airway from aspiration of material into the airway and lung.

• The oesophageal phase is the involuntary phase that utilises peristalsis to propagate the food/liquid bolus through the oesophagus into the stomach. The oesophagus is bound by upper and lower sphincters (the upper formed by the cricopharyngeus muscle), which prevent retrograde flow from the stomach to regurgitate.