Nasopharynx
The nasopharynx forms the superior-most part of the pharynx, in continuity with the inferior oropharynx, and the posterior continuation of the anterior nasal cavity.
Gross anatomy
Boundaries
- anteriorly: posterior nares and posterior margin of nasal septum
- inferiorly: soft palate
- superiorly: basisphenoid and basiocciput
- roof of the nasopharynx is called the vault (or fornix) of the pharynx, where the mucosa firmly attaches to the sphenoid and pharyngobasilar fascia
- posteriorly: C1 and C2
- laterally
- the pharyngeal opening of the Eustachian tube is located in the center of the lateral wall
- lymphoid tissue aggregates, also known as the tubal tonsil occur around the opening of the Eustachian tube
- the fossa of Rosenmüller lies between the posterior margin of the Eustachian tube and the posterior wall of the nasopharynx
Blood supply
- arteries
- ascending pharyngeal artery
- ascending palatine branch of facial artery
- ascending cervical artery
- maxillary artery
- veins: occur as plexi which drain into the internal jugular vein
- pterygoid plexus
- pharyngeal plexus
Lymphatic drainage
Lymphatic drainage in the nasopharynx occurs laterally and medially:
- lateral drainage pathway: lymph vessels traverse the superior constrictor muscle and drain into the lateral retropharyngeal, deep cervical and posterior triangle lymph nodes
- medial drainage pathway: lymph vessels from the roof and posterior wall drain into the median retropharyngeal lymph nodes
Innervation
- sensory
- pharyngeal nerve of the maxillary division of the trigeminal nerve (CN Vb)
- glossopharyngeal nerve (CN IX)
- motor
- pharyngeal plexus: contains branches of cranial nerves IX and X together with sympathetic fibers