Cranial Nerves

Question 1

What is the cranial nerve exam for Olfactory nerve 1?

Answer 1

Smell
Citrus smells

Question 2

What is the cranial nerve exam for Optic nerve 2?

Answer 2

Visual activity
Visual field - look at nose
Pupillary reflexes - shine light

Question 3

What are the possible lesions based on optic nerve testing?

Answer 3

Left optic nerve lesion - left direct lost, right consensual lost
Left oculomotor nerve lesion - left direct and consensual lost

Question 4

Which nerves are afferent and efferent visual testing?

Answer 4

Afferent - optic nerve
Efferent - oculomotor nerve

Question 5

What muscles do oculomotor, trochlear, abducens nerve 3, 4, 6 supply?

Answer 5

Extraocular muscles
Oculomotor - recuts, inferior oblique, efferent pupils
Trochlear - superior oblique
Abducens - lateral rectus

Question 6

What is the cranial nerve exam for oculomotor, trochlear, abducens nerve 3, 4, 6?

Answer 6

Eyelid droop
Ask patient to keep her still and follow finger
Check lateral and vertical

Question 7

What does oculomotor 3rd nerve palsy look like?

Answer 7

Caused by berry aneurysm, diabetes
Unilateral ptosis
Eye looks down and out
Dilated pupil
Pupil fixed to light

Question 8

What does trochlear 4th nerve palsy look like?

Answer 8

Double vision
Looking down and in

Question 9

What does abducens 6th nerve palsy look like?

Answer 9

Double vision
Looking laterally

Question 10

What are the causes of unilateral ptosis?

Answer 10

Horners syndrome - constricted pupil
3rd nerve lesion

Question 11

What nerve provides facial sensation and masticatory muscles?

Answer 11

Trigeminal nerve:
Ophthalmic
Maxillary
Mandibular

Question 12

What are the tests for sensory and motor function of trigeminal nerve 5?

Answer 12

Sensory - light touch
Motor - ask patient to clench, palpate muscles

Question 13

What are the effects of upper motor neruon lesion of trigeminal?

Answer 13

Affects just the mouth

Question 14

What are the effects of lower motor neuron lesion of trigeminal?

Answer 14

Affects forehead and mouth

Question 15

What are the effects of motor lesions of trigeminal nerve?

Answer 15

Wasting of temporalis and masseter
Jaw opening deviates to side of lesion
Jaw reflex

Question 16

What cranial nerve provides facial movements?

Answer 16

Facial nerve 7

Question 17

What are the motor and sensory tests for facial nerve 7?

Answer 17

Motor - facial expression, provide submandibular, sublingual salivary glands
Sensory - taste to anterior 2/3 tongue

Question 18

What are the effects of lower motor neuron lesion of the facial nerve?

Answer 18

Bell’s palsy
Viral
Parotid surgery or tumour
Unilateral facial palsy
Loss of taster anterior 2/3

Question 19

What are the effects of the upper motor neuron lesion of the facial nerve?

Answer 19

CVA
Unilateral facial palsy
Contra lateral
Forehead is spared - bilateral innervation to forehead

Question 20

What cranial nerve provides hearing?

Answer 20

Vestibulo chochlear nerve 8

Question 21

How do you test for vestibulocochlear nerve 8?

Answer 21

Whisper a number in one ear while masking the other

Question 22

What are some consequences of vestibular dysfunction?

Answer 22

Vertigo
Poor balance
Nystagmus

Question 23

What cranial nerves controls speech, swallow, palatal movement?

Answer 23

Glossopharyngeal
Vagus

Question 24

What sensory deos glossopharyngeal nerve 9 provide?

Answer 24

Sensory to tonsil lar fossa
Pharynx
Taste posterior 1/3 of tongue

Question 25

What are the effects of a glossopharyngeal nerve lesion?

Answer 25

Nasopharyngeal tumour Depressed gag reflex

Question 26

What motor function does the vagus nerve provide?

Answer 26

Motor to palate, pharynx, larynx Check by saying ahhh for palatal movement

Question 27

What are the effects of 9th or 10th nerve lesion?

Answer 27

Dysarthria - difficulty speaking

Question 28

How do you test for the accessory nerve 11?

Answer 28

Shoulder shrug against resistance Rotation of head against resistence

Question 29

What motor innervation does accessory nerve 11 supply?

Answer 29

Motor to sternocleidomastoid and trapezius

Question 30

What cranial nerve controls tongue movement?

Answer 30

Hypoglossal

Question 31

What is indicative of a lower motor neuron lesion of the hypoglossal?

Answer 31

Wasting Fasciculations Deviation of tongue to side of lesion

Question 32

What are the effects of an upper motor neuron lesion in the hypoglossal?

Answer 32

Bilateral Tongue spasm Movements slow and limited

Question 33

What happens in there is cerebellar lesion of the tongue?

Answer 33

Alternating tongue movements Slow and irregular

Question 34

What are the causes of Horners syndrome?

Answer 34

Interruption of sympathetic fibres to one eye Cervical cord Lung tumour spread Neck trauma Malignant lymph nodes

Question 35

What type of disorder is bulbar palsy?

Answer 35

Lower motor neruon Could be motor neurone disease, tumour in medulla Tongue wastes

Question 36

What type of disorder is pseudobulbar palsy?

Answer 36

Upper motor neuron disorder Due to bilateral lesions- stroke, MS Caused by paralysis of lower cranial nerves Slurred speech, Dysphagia, hoarse voice Tongue not wasted - slow and stiff movements