[Plate 66, Pharynx: Opened Posterior View]page 38
page 39The pharynx is a muscular tube, which is deficient anteriorly as a result of the openings nasal and oral cavities and larynx-as revealed when the
posterior wall is removed.
Muscular tube
Posterior to nasal and oral cavities
Continuous with both esophagus and larynx
Anterior to superior six cervical vertebrae and prevertebral muscles and fascia
Retropharyngeal space = potential space between pharynx and prevertebral fascia
Divided into three parts: Nasopharynx, Oropharynx, and Laryngopharynx
Nasopharynx
Posterior to nose and above soft palate
Lined with ciliated epithelia
Boundaries
Anteriorly: continuous with nasal cavities via choanae
Roof and posterior wall: body of sphenoid and base of occipital bone
Laterally: superior constrictor muscle
Contains openings of auditory (Eustachian) tubes (from middle ear)
Salpingopharyngeal fold
Extends inferiorly from medial end of auditory tube
Covers salpingopharyngeus muscle-opens tube during swallowing
Ridge over opening = torus tubarius
Pharyngeal recess
Slit-like projection
Posterior to torus
Contains abundant lymphoid tissue
Incomplete ring in superior part of pharynx
Aggregates in certain areas = tonsils
Lymphoid tissue in mucus membrane of roof and posterior wall = adenoids
Lymphoid tissue near opening of auditory tube = tubal tonsil
Oropharynx
From soft palate to superior ends of epiglottis