Week 6

Question 1

where are the receptors for the olfactory nerve

Answer 1

caudal aspect of nasal cavity in respiratory epithelium

Question 2

where are the axons for olfactory nerve

Answer 2

in cribiform plate; travel as lateral olfactory tract to paleopallium to piriform lobe; some travel in medial olfactory tract to hypothalamus for unconscious smell perception

Question 3

usually damage to olfactory nerve occurs where?

Answer 3

peripherally

Question 4

where are receptors for optic nerve

Answer 4

retina to optic disc

Question 5

where are the axons for optic nerve

Answer 5

optic nerve, through optic canal, to optic chiasm; to optic tracts,
to LGN and occipital lobe for conscious vision
to PTN for unconsious vision

Question 6

what do you see when optic nerve is damaged

Answer 6

visual deficits or blindness

Question 7

PLR if lesion cranial to chiasm

Answer 7

no plr

Question 8

plr if lesion caudal to chiasm

Answer 8

plr present

Question 9

where does most causes of blindness occur

Answer 9

in the eye

Question 10

how else can you assess optic nerve

Answer 10

menace response

Question 11

when you have compression of the oculomotor nerve, what innervation goes first?

Answer 11

parasympathetic innervation, then somatic innervation

Question 12

somatic signs of damage of oculomotor

Answer 12

ventrolateral strabismus in SA and lateral strabismus in LA

Ptosis

Question 13

what are the signs of damage of GVE oculomotor nerve

Answer 13

mydriasis

Question 14

what do you see if the trochlear nerve is damaged

Answer 14

rotary strabismus (hard to assess in dogs); not clinically relevent

Question 15

what do you see if the abducens nerve is damaged

Answer 15

medial deviation of globe

Question 16

how do you assess II, IV, VI

Answer 16

look at position and movement of eye; oculocephalic reflex

Question 17

where does the split for the trigeminal come occur

Answer 17

inside the brain case

Question 18

where does the ophthalamic nerve exit

Answer 18

the orbital fissure (dog and horse)

foramen orbitorotundum in ox

Question 19

where does the maxillary nerve

Answer 19

rostral alar foramen via round foramen (dogs and horse)
foramen orbitorotundum (ox)

Question 20

what is sensory to the external ear canal

Answer 20

CN VII

Question 21

What is sensory to the caudal pinna

Answer 21

C2 spinal (greater auricular nerve)

Question 22

trigeminal is motor to

Answer 22

muscles of mastication

Question 23

know az in small animals and horse and ruminants

Answer 23

notes pg. 109-110

Question 24

what occurs when you damage the trigeminal nerve

Answer 24

anesthesia and deficitis with palpebral, corneal, and trigeminofacial reflexes; LMN signs of muscles of mastication (via mandibular nerve); protrusion of the third eyelid due to atrophy of pterygoid muscles;

Question 25

how can you assess trigeminal nerve (besides relfexes)

Answer 25

open mouth to assess jaw strength in unilateral flaccid paralaysis (if bilateral- drop jaw)

Question 26

facial nerve is motor to

Answer 26

muscles of facial expression and lacrimal gland (gve parasympathetic)

Question 27

facial nerve exits via

Answer 27

stylomastoid foramen

Question 28

what are the 3 main branches of the facial nerve

Answer 28

``` buccal branches (dorsal and ventral; only 1 branch in horse) auriculopalpebral n. (innervates orbicularis oculi m. via palpebral nerve) ```

Question 29

what do you see when the facial nerve is damaged

Answer 29

facial paralysis; check for normal tearing! (a lot of times tearing will be ok; already split from facial at stylomastoid foramen and hitches a ride with ophthalamic)

Question 30

damage of facial in dog and cat

Answer 30

nasal deviation occasionally seen in dog

Question 31

facial damage in horse

Answer 31

nasal deviation to opposite side of damage; ptosis (angularis oculi m.) (can view by angle of lashes)

Question 32

facial nerve damage in cattle

Answer 32

ptosis (angularis oculi m.)

Question 33

otitis media interna

Answer 33

can damage CN VII and VII;

Question 34

medulla compressive tumors

Answer 34

VN VII brings info to medulla close to VII so can see with central and periptheral lesions (vestibular dz and loss of senstion of inner ear and other facial nerve signs)

Question 35

vestibular component of vestibulocochlear receptors are in

Answer 35

inner ear in semicircular canals; utricle and macula

Question 36

damage to cochlear component

Answer 36

deafness almost always a peripheral problem (some drugs are ototoxicl- aminoglycosides; congenital deafness- linked to white hearcoat)

Question 37

vestibular component damage

Answer 37

vestibular disease; head tilt; vestibular dz is a unilateral dz and can be unilateral centrally or unilateral peripherally

Question 38

glossopharyngeal nerve is motor to

Answer 38

pharyngeal muscles (involuntary phase of swallowing)

Question 39

glossopharyngeal nerve sensory to

Answer 39

pharyngeal mucosa

Question 40

vagus nerve sensory to

Answer 40

pharyngeal mucosa and larynx, trachea

Question 41

vagus nerve motor to

Answer 41

pharynx, larynx, esophagus

Question 42

what do you see if you damage CNN IX, X

Answer 42

``` dysphagia (9 and 10) dysphonia (x) inspiratory dyspnea (x) megaesophagus (x) cardiovascular changes ```

Question 43

hypoglossal nerve motor to

Answer 43

tongue

Question 44

damage of hypoglossal nerve

Answer 44

atrophy (typically lateral) | dyspagia (bilateral)