Branches from
Ascending pharyngeal
Lingual
Ascending and descending palatineVenous drainage
External palatine vein → pharyngeal plexus
Pharyngeal venous plexus → internal jugular veinLymphatic drainage
General drainage to deep cervical nodes
From tonsillar tissue to nodes near angle of mandible and tonsillar (jugulodigastric) nodeInnervation
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From pharyngeal plexus (motor and almost all sensory)
Motor
From pharyngeal plexus via vagus nerve from cranial root of accessory nerve (cranial nerve [CN] XI)
To all muscles of pharynx except stylopharyngeus (CN V 2 )
Branches from external and recurrent branches of vagus
To inferior constrictor
Sensory
Mainly from glossopharyngeal nerve (CN IX) via plexus
Also
Maxillary nerve (CN V 2 ) to anterior and superior nasopharynx
Tonsillar nerves from branches of glossopharyngeal and vagus (CN X)Swallowing (deglutition)
Occurs in three stages
1 = voluntary
Food is in the mouth, breathing occurs through the nasopharynx
Food is chewed (masticated) and mixed with saliva to produce a bolus
Bolus of food is compressed against hard palate
Palatoglossal folds relax
Muscles of tongue and soft palate push bolus into oropharynx
Cycle lasts 1 to 2 seconds
2 = involuntary
Reflexive, mediated via glossopharyngeal nerve
Nasopharynx is closed off by tension and elevation of the soft palate
Prevents reflux of food/fluids into the nose
Mediated by tensor veli palatine and levator veli palatine muscles
Suprahyoid muscles and longitudinal pharyngeal muscles contract
Elevate larynx
Close epiglottis
Propel bolus
3 = involuntary
Food propelled through the pharynx by peristalsis (sequential contraction of all three constrictors)
On reaching the distal end of pharynx, high pressure causes relaxation of terminal part of inferior constrictor
Called cricopharyngeus muscle
Serves as superior esophageal sphincter
Food enters the oesophagus
As bolus passes pressure drops, the sphincter closes
Larynx and epiglottis return to normal positions