Cranial Nerves/ophtho

Question 1

Signs that vertigo is central

Answer 1

NO nystagmus latency (nystagmus starts right after maneuver)
Nonfatiguing nystagmus, lasts > 1 min
Nystagmus not suppressed by visual fixation
VERTICAL nystagmus. pure torsional (rarely periph)
vertigo subjectively less severe in central vs periph
other neuro probs - gait issues, falls, ataxia
no hearing change or tinnitus

Question 2

What runs thru cavernous sinus

Answer 2

The carotid siphon of the internal carotid artery, and cranial nerves III, IV, V (branches V1 and V2) and VI

Question 3

signs that Bell’s palsy will have good prognosis

Answer 3

incomplete Bell’s
improvement in within 3 weeks

Question 4

when to image “Bell’s palsy”

Answer 4

slowly progressing more than 3 weeks
no improvement at 6 months

Question 5

slow vs fast phase nystagmus

Answer 5

slow phase towards affected/bad side, with fast correction towards good side.

amplitude increases looking towards good side

Question 6

what are the vestibular sensory organs

Answer 6

semicircular canals and the otolithic organs (saccule and utricle)

Question 7

what motions of head do semicircular canals and otolithic organs detect?

Answer 7

otolithic organs (saccule + utricle) - LINEAR/VERTICAL
semicircular canals - ANGULAR

Question 8

which nerves innervate anterior and posterior bellies of the digastric muscle?

Answer 8

anterior - trigeminal
posterior - facial nerve
(fivecomesaheadof7)

Question 9

VOR

Answer 9

communication between semicircular canals and oculomotor nerves to keep eyes fixed on object as head moves

Question 10

cold calorics - normal healthy brain response?

Answer 10

causes tonic deviation of eyes to the same ear you are squirting cold water in (if intact brainstem), eventually followed by corrective fast nystagmus away from the cold water (if intact cortical circuits)
COWS - cold opposite, warm same

Question 11

localize the facial nerve lesion: face weakness + altered taste and hearing. normal lacrimation.

Answer 11

lesion between the geniculate ganglion and stapedius nerve

Question 12

localize the lesion: face weak + altered taste. normal hearing and lacrimation.

Answer 12

lesion between the stapedius nerve and chorda tympani

Question 13

what branch of the facial nerve arises from the geniculate ganglion?

Answer 13

greater petrosal nerve - parasympathetic
travels to pterygopalatine ganglion, from which fibers travel to supply lacrimal and mucosal glands of nose and mouth

Question 14

branches of facial nerve in order from proximal-distal

Answer 14

greater petrosal (from geniculate ganglion)
stapedius nerve
chorda tympani nerve
then all the face muscle branches

Question 15

which nerve innervates all the glands in the head/face except the parotid glands?

Answer 15

facial nerve

Question 16

which nerve innervates the parotid glands?

Answer 16

glossopharyngeal

Question 17

which CN nucleus supplies parasympathetics to head/neck?

Answer 17

SSN - superior salivatory nucleus

Question 18

nucleus tractus solitarius

Answer 18

involved in both taste(SALTITARIOUS) and baroreceptor reflexes

receives taste afferents from facial nerve (ant 2/3 of tongue), glossopharyngeal nerve (posterior 2/3 tongue) and vagus nerve (base of tongue, epiglottis, pharynx)

receives baroreceptor afferents from glossopharyngeal nerve –> nuc tractus solitarius –> dorsal motor nucleus of vagus is stimulated to slow HR

Question 19

nucleus ambiguus

Answer 19

innervates muscles of larynx and pharynx (glossopharyngeal and vagus nerves)

Question 20

superior salivatory nucleus

Answer 20

parasympathetic innervation to head and neck

Question 21

inferior salivatory nucleus

Answer 21

innervates parotid gland via glossopharyngeal

Question 22

cornea sensation

Answer 22

upper 1/2 - V1
lower 1/2 - V2

Question 23

gasserian ganglion

Answer 23

where the 3 branches of trigeminal arise from

Question 24

sphenopalatine ganglion

Answer 24

parasympathetic ganglion assoc with trigeminal nerve–> lacrimal glands, paranasal sinuses, glands of mucosa of nose and pharynx, gingiva, mucus membrane and glands of hard palate

this is what is involved in TACs

Question 25

SCM vs trap localization

Answer 25

SCM - ipsi motor cortex
trap - contralateral motor cortex

Question 26

where do the branches of trigeminal pass through?

Answer 26

V1 - superior orbital fissure
V2 - foramen rotundum
V3 - foramen ovale (o-valley - for lowest branch)