What is a Pharyngeal Tonsil?

Tonsils are aggregates of lymphoid tissues located in the pharynx. The pharynx, more commonly called the throat, is the uppermost part of the aerodigestive system that allows the passage of food into the esophagus and air into larynx. It is connected to the nose via the nasopharynx, an extension of the nasal cavities. A pharyngeal tonsil is a type of tonsil located on the roof and posterior walls of the nasopharynx. An inflamed pharyngeal tonsil is more popularly known as adenoid, which can cause symptoms of obstruction.

In humans, the tonsils serve as part of the lymphatic system. The four types of humans tonsils are tubal tonsils located on the roof of the pharynx, palatine tonsils located between the palatopharyngeal and palatoglossal arches, lingual tonsils located behind the tongue, and pharyngeal tonsils located on the roof of the pharynx. All of these tonsils grow to their largest size before puberty and undergo atrophy later on.

Like the other types of tonsils, the purpose of pharyngeal tonsils is to enhance the capabilities of the lymphatic system against foreign agents that enter through the mouth and nose, and pass through the throat. In infants, enlargement of the lymphoid tissues occurs as a defense mechanism against infections. This enlargement can cause a significant obstruction of the airway, leading to pharyngeal tonsil problems such as mouth respiration and snoring.

A child with adenoid enlargement or hypertrophy may have an atypical appearance called adenoid facies. Examples of adenoid facies include mouth breathing, open mouth, elevated nostrils, prominent incisors, elongated face, short upper lip, hypoplastic maxilla, and high arched palate. These are adaptive measures to obstruction.

Enlarged adenoids also increase the pressure on or obstruct the Eustachian tubes, which connect the nasopharynx to the ears. When an increase in pressure or obstruction occurs, the tympanic membrane of the ear may become inflamed, leading to a painful ear condition called otitis media. Untreated otitis media can result in hearing loss. Other consequences of an enlarged pharyngeal tonsil include chronic colds, sinusitis, and bronchitis. These are the reasons why a pharyngeal tonsil operation is recommended.

Treatment of pharyngeal tonsils is done through adenoidectomy, after the administration of a general or topical anesthetic. Surgical procedures include curettage, cauterization, laser therapy, and ablation. Despite differences in mechanisms, the aim of these surgical procedures is to remove enlarged adenoids, although as many as 20% of people who undergo adenoid removal experience recurrence.