Pharyngeal plexus of nerves

Contributors:

  • Vagus nerve (motor and sensory)
  • Glossopharyngeal (sensory)
  • Sympathetic nerves from superior cervical ganglion.

Location: Surface of pharynx

Distribution: Palate and pharynx (constrictors)

 
Piriform recess (fossa)

Location: Each side of pharynx.

Clinical importance:

  • Foreign bodies e.g. fish bones, pea nuts can lodge there.
  • Favourite hiding place for tumours.
  • Internal laryngeal nerve in the wall can be injured.
 
Retropharyngeal space

Location: Behind the pahrynx.
 

Relations:

  • Anterior: Posterior wall of pharynx.
  • Posterior: Prevertebral fascia.
  • Laterally: Carotid sheath and sympathetic chain.
  • Contents: Loose areola tissue and retro pharyngeal lymph nodes.
  • Clinical importance: Retropharyngeal abscess, from infection.
Waldeyer's lymphatic ring
Components: Pharyngeal, tubal, palatine and lingual tonsils. They have no afferents.

Connections: Retro pharyngeal, styloid, lateral pharyngeal, jugular chain, submandibular, submental.

Function: Protection.
 
Palatine tonsils

Location: Lateral wall of pharynx.

Relations:

Anterior: Palatoglossal fold

Posterior: Palatopharyngeal fold

Superior: Soft palate

Inferior: Dorsum of tongue

Lateral: Superior constrictor, facial and lingua; arteries


 

 Blood supply:

  • Tonsilar branches of:

    (+) Facial
    (+) Lingual
    (+) Ascending pharyngeal
    (+) Maxillary.
    (+) Palatine

    Most of these enter the lower half of the tonsil but the descending palatine enter the upper pole and may cause troublesome hemorrhage.

Veins form tonsilar plexus which enters pahryngeal plexus to internal jugular and therefore communicate with the cavernous sinus.

The external palatine vein descends from soft palte and can cause troublesome bleeding.

Lymphatic drainage: Superior deep cervical especially jugulodigastric and retro pharyngeal nodes.

Innervation: Glossopharyngeal and lesser palatine.

Clinical importance: Tonsilitis, tonsillectomy, tonsillar abscess, referal pain to the ear; retro pharyngeal abscess.
 

 
 

The Oral cavity and Pharynx