The adenoids are a mass of lymphoid tissue in the roof of the nasopharynx, located just inferior to the sphenoid sinus and anterior to the basi-occiput. laterally, the adenoids blend with the lymphoid tissue of thefossa of Rosenmullernear the opening of the eustachian tube.
The adenoids are present in all infants and children, and start to regress just before puberty. They are usually absent in adults.
Large adenoids produce nasal obstruction, mouth breathing, nasal voice, snoring and restless sleep. Chronic mouth breathing during the age when the facial bones are changing toward the adult configuration often produces a high arched palate, the pinching in of the nose and a shortened upper lip, with a staring expression of the eyes. The face becomes slightly elongated and the upper teeth may be prominent. These changes are called adenoid facies.
In addition, hypertrophy of the adenoids may also produce obstruction of the eustachian tubes and contribute to the formation of middle ear effusions.