On the lateral wall of the nasopharynx, identify the opening of the pharyngotympanic (auditory or Eustachian) tube. This ostium is formed superiorly by the prominence of the cartilage of the auditory tube, the torus tubarius. Extending from the torus tubarius is the salpingopharyngeal fold which covers the salpingopharyngeus muscle.
Immediately posterior and superior to the torus tubarius, identify the pharyngeal recess. Locate the pharyngeal tonsil or "adenoids" that lie in the roof and posterior wall of the nasopharynx. This lymphatic tissue may be enlarged during childhood and obstruct air passage from the nasal cavity to the pharynx.
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