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The nasopharynx has a respiratory function; it is the posterior extension of the nasal cavities.
- Location: Behind nasal cavity and above the soft palate.
- Boundaries (Relation to wall)
- Anterior wall
- Deficient and communicates with nasal cavity via choanae.
- Roof and Posterior wall
- Form continuous surface that slopes downwards backwards supported by body of sphenoid, occipital bones (basilar part) and anterior arch of atlas.
- Features
- Naso-pharyngeal tonsil
- Formed by aggregation of lymphoid tissue beneath the mucus membrane.
- Pharyngeal bursa (Pouch of Luschka)
- It is mucus diverticulum extending upwards into substance of naso-pharyngeal tonsil.
- Pharyngeal hypophysis
- Some of nasopharyngeal roof resemble histologically to adenohypophysis.
- Cells are derived from backward extension of Rathke's pouch (site for craniopharngioma).
- Floor
- Communicates with oro-pharynx via pharyngeal isthmus.
- Bounded infront by posterior surface and free margin of soft palate, and behind by mucous elevation of Passavant's ridge.
- On each side: Palato-pharyngeal arch contains muscle palato-pharyngeus.
- Lateral wall:
- Features:
- Pharngeal opening of auditory tude
- Tubal elevation
- Pharyngeal recess (Fossa of Rosenmuller)
