2 - ENT - Facial Nerve - Course, function and branches of FN CNVII

Question 1

Facial nerve - origin and path until exits cranial cavity?

Answer 1

from lateral surface of brainstem as two roots (M+S) - between pons and medulla

crosses posterior cranial fossa - exits cranial cavity through internal auditory meatus

Question 2

Path of facial nerve from internal auditory meatus to stylomastoid foramen

Answer 2

enters facial canal (temporal bone) - roots merge to form facial nerve

genticulate ganglion – Greater Petrosal nerve given off (inner. lacrimal gland and recieves taste from palate)

continues through facial canal

• gives nerve to stapedius
• gives chorda tympani (anterior 2/3rds tongue, SML/SLingual salivary glands)

facial nerve then exits through stylomastoid foramen

Question 3

Sensory function of facial nerve

Answer 3

taste from tongue/palate

Sensation from small area of EAM and around auricle

Question 4

Other functions of facial nerve

Answer 4

motor innervation of muscles of facial expression

SML/SLingual salivary glands

Question 5

first two major branches of facial nerve + path/+ function

Answer 5

Posterior auricular nerve - up posterior to ear - inn. > post auricular muscle, occiptal belly of occipitofrontalis
digastric branch - digastric and stylohyoid muscle

Question 6

what happens after entering the parotid gland

Answer 6

divides into temperofacial and cervicofacial branches

Question 7

How does the facial nerve leave the parotid + regions innervated

Answer 7

To Zanzibar By Motor Car

Temporal - temple, forehead + supra orbital
Zygomatic - infra-orbital, nasal, upper lip
Buccal - cheek, upper lip, corner of mouth
Marginal Mandibular - lower lip and chin
Cervical - platysma