Parotid Region & Facial Nerve Flashcards
where is the parotid region?
anterior to the each and inferior to the zygomatic arch
what is the parotid gland?
the largest of the salivary glands
- produces mostly serous secretions
what is the parotid enclosed in?
Enclosed in the parotid sheath
- tough fascial capsule derived from investing layer of deep cervical fascia
what muscle does the parotid duct pierce?
buccinator
what structures are embedded in the parotid gland?
- retromandibular vein
- external carotid artery
- parotid lymph nodes
- CNVII
what is the parasympathetic innervation of the parotid gland?
- preganglionic fibres from the Glossopharyngeal nerve (CNIX) travel to the otic ganglion in the tympanic nerve & lesser petrosal nerve
- post ganglionic fibres from the otic ganglion pass to the auriculotemporal nerve (CNV3) that sens branches to the parotid gland
what supplies blood to the parotid gland?
the parotid gland receives its arterial supply from the branches of the external carotid that run through it
what is the venous drainage of the parotid gland?
- maxillary vein
- superficial temporal vein
what is the sympathetic innervation of the parotid gland?
- derived from the superior cervical ganglion & nerve plexus on the ECA
what does sympathetic activation of the parotid gland result in?
vasoconstriction & reduction in volume of saliva (leading to dry mouth)
what foramena does the facial nerve travel through?
internal acoustic meatus
describe the facial nerve supply to the tongue:
the chorda tympani branches off the facial to hitchhike with the lingual nerve
- supplies taste & sensation to the anterior 2/3 of tongue
where does the facial nerve exit the skull?
stylomastoid foramen
when the facial nerve exist the skull, what are the two branches that it immediately gives off?
- posterior auricular
- digastric branch
what does the posterior auricular nerve supply?
- auricularis posterior
- occipital belly of the occipitofrontalis muscle
what does the digastric branch of the facial nerve supply?
the posterior belly of the digastric
what are the 5 terminal branches of the facial nerve?
- temporal
- zygomatic
- buccal
- marginal mandibular
- cervical
During a parotidectomy, the patient suffers from damage to the zygomatic branch of the facial nerve, what would occur?
- paralysis
- loss of tonus of orbicularis oculi in the inferior eyelid causing it to EVERT
- damage of cornea
- impaired vision
what occurs if the buccal branch of the facial nerve is damaged?
paralysis of buccinator & superior portion of orbicularis oris & upper lip muscles
what is Bell’s palsy?
unilateral facial paralysis in the upper and lower portions of the face, with no apparent cause for the paralysis
what may be used to treat Bell’s Palsy?
- steroids
- anti-viral medication
how is the parotid gland related to the viral infection mumps?
The most common & recognisable symptom is swelling of the parotid gland
