CN7- Facial nerve

Question 1

what are the two components of the facial nerve

Answer 1

Facial n proper and Intermediate

Question 2

what are the components of the facial n proper

Answer 2

visceral m- muscles of facial ex, stapedius, stylohyoid

general somatosensory- auricle

Question 3

what are the components of the facial n intermediate

Answer 3

Has parasympathetic components

Greater petrosal- to pterygopalantine ganglion

Lesser petrosal- to submandibular ganglion

Question 4

General passage of the facial nerve

Answer 4

will run into the internal acoustic meatus will pass over cochlea and then make a 90 degree turn (genu) to go cuadally and exit out the stylomastoid foramen

Question 5

what branches does the facial nerve give before it exits out of the stylomastoid foramen in middle ear

Answer 5

stapedius m

Question 6

Path of greater petrosal n

Answer 6

enters interal auditory meatus runs through greater petrosal foramen and foramen lacerum + pterygoid callan to the ptergopalantine fossa

Question 7

path of lesser petrosal n

Answer 7

enters internal auditory meatus and exit thru petrotympanic fissure in middle ear

Question 8

what path does CNV use

Answer 8

greater petrosal

Question 9

where does greater petrosal n synapse and lead to

Answer 9

Pterygopalantine ganglion to lacrimal, nasal mucosal and oral mucosal glands

Question 10

where does lesser petrosal n synapse and lead to

Answer 10

submandibular ganglion out side petrotympanic fissure

to submandibular and sublingual salvary glands

Question 11

where is the internal carotid artery found and what surronds it

Answer 11

surrounded by parasympathetic postganglionic plexus that connects to the great persal n via deep persoal

Question 12

where does sensory from the ant 2/3 of the tongue and taste from soft palate run with

Answer 12

ant tongue with lesser petrosal
soft palate with greater petrosal

both synapse at genicular ganglion

Question 13

what does the motor root of the facial nerve run thru after it exits out of the stylomastoid process

Answer 13

enters into the parotid gland forming parotid nerve plexus (does not innervate it tho)- the branches will then emerge under the gland and go to its targets

Question 14

what is paratiditis and what can it cause

Answer 14

viral infection causes swelling and pain which can in turn compress CN7

Question 15

main branches of facial n from top to bottom

Answer 15

temporal
zygomatic
buccal branches
Marginal mandibular 
cervical

Question 16

what is bells palsy generally due to and generally affects

Answer 16

lower motor neuron lesion of brachiomotor component which causes same side paralysis of facial m (drooping on one side

Question 17

what are the 3 sites that the nerve can be affected in bells palsy

Answer 17

A- motor nuclei
B- Internal auditory meatus
C- Stylomastoid foramen

Question 18

When could sound be distorted in bells palsy

Answer 18

if nerve was affected at motor nucli or internal auditory meatus (but NOT stylomastoid foramen)

Question 19

What is crocodile tears syndrome

Answer 19

during recovery from bells palsy, regenerating salviary fibres in the facial n become misdirected and innervate the lacrimal gland

as result stim such as smell may produce simultaneous flow of tears on side of bells palsy

Question 20

branches of the aoritic arch

Answer 20

LCCA
LSA

Brachiocephalic trunk-> right subclavian and RCCA

Question 21

what does the common carotid artieries give rise too and location of them

Answer 21

splits into ext and int carotic artery (ext is located medially @ bifurcation then at base of skull it will switch back)

Question 22

which carotid artery doesnt have any branches in the neck region

Answer 22

internal ( thus if u see branches right at the bifurcation u know it has to be external)

Question 23

what are the 2 terminal branches of the ext carotid

Answer 23

maxillary (which splits off at lvl of mandible)

Superficial temporal

Question 24

where is the facial artery pulpasion most palpable

Answer 24

where it crosses the mandibular body

Question 25

where does the internal carotid vein go and what drains into it

Answer 25

descends thru jugular foramen (deep to scm) eventually joins sup vena cava

-all blood from dural sinus, facial vein, opthalmic vein

Question 26

what drains into the external carotid and where does it go

Answer 26

gets bood from post auricular and drains in subclavian v

Question 27

drainage of lymph from head/neck

Answer 27

superficial lymph ring drains into deep cervical lymph nodes along internal jugular vein which eventually drain into that vein

Question 28

how do you test the buccinators and orbiularis oris

Answer 28

tested by asking the pt to press lips firmly together or to blow cheeks

Question 29

how to test taste buds

Answer 29

add taste to either side of tougue and see if different

Question 30

how to test lacrimal and salvitory gland function

Answer 30

direct questioning about pressence of dry eyes/dry mouth

Question 31

how to test function of stapedius

Answer 31

clapping beside each ear to see change one to the other

if sound is loud then stapedius likely affected