adenoids

Adenoids, or pharyngeal tonsils, are a mass of lymphoid tissue located on the roof of the nasopharynx, behind the soft palate. They form part of Waldeyer's ring, a ring of lymphoid tissue that guards the upper throat and nasal passages.

In childhood they play a role in the immune system by sampling inhaled bacteria and viruses and producing antibodies. The adenoids are most active in early life and typically shrink during adolescence as part of normal immune development.

Enlargement (hypertrophy) can obstruct nasal breathing, leading to chronic mouth breathing, snoring, and sleep-disordered breathing. Enlarged adenoids can block the openings of the Eustachian tubes, contributing to middle-ear infections and fluid buildup (otitis media with effusion) and hearing difficulties.

Diagnosis is usually clinical, supported by nasal endoscopy or flexible nasopharyngoscopy. Imaging is not routinely required, but lateral radiographs or CT may be used in complex cases. Audiometry and tympanometry assess hearing and middle-ear status.

Treatment depends on severity. Many cases improve with time or respond to intranasal corticosteroids. Antibiotics may be used for acute infections. Adenoidectomy—often performed alongside tonsillectomy (adeno-tonsillectomy)—is considered for persistent obstruction, sleep-disordered breathing, or recurrent otitis media with effusion.

Adenoids are less prominent in adults, and surgery is less common in older individuals. Complications of removal are uncommon but can include bleeding and, rarely, velopharyngeal insufficiency.