cranial nerve exam

Question 1

how do you test cranial nerve 1?

Answer 1

olfactory nerve - ask about alteration in sense of smell

Question 2

how do you test cranial nerve 2?

Answer 2

optic nerve:
- visual acuity: how many fingers am I holding up?
- visual fields: cover opposite eyes and bring finger into each corner of visual field
- visual inattention: hold hands in periphery and ask which finger moves
- direct / consensual light reflexes: ask pt to look straight ahead not focussing on light. shine light into pupil and look for constriction of that pupil and contralateral pupil
- accommodation: look into distance then focus on finger quickly

Question 3

how do you test cranial nerves 3, 4 and 6

Answer 3

oculomotor, trochlear and abducens: ask pt to keep head still and follow your finger with their eyes. slowly trace a large H and I shape with finger

Question 4

how do you test for cranial nerve 5?

Answer 4

trigeminal nerve:
- sensation: cotton wool on sternum then on dermatomes of the face
- motor: ask pt to clench jaw and palpate jaw and open mouth against resistance
- jaw jerk: place index finger on middle of jaw and tap tendon hammer.

Question 5

how do you test cranial nerve 7?

Answer 5

facial nerve:
- ask pt to screw up their eyes and not let you open them
- ask to puff out their cheeks, raise their eyebrows, purse their lips and show your their teeth

Question 6

how do you test cranial nerve 8?

Answer 6

vestibulocochlear nerve:
- cover the opposite ear with hand and whisper a number to pt and ask them to repeat
- rinne’s and weber’s test

Question 7

how do you test cranial nerve 9 and 10?

Answer 7

glossopharyngeal and vagus nerves:
- ask pt to open their mouth wide and assess whether uvula is in the midline, ask pt to say “ahh”
- ask pt if they have any difficulty swallowing
- ask pt to cough

Question 8

how do you test cranial nerve 11?

Answer 8

accessory nerve:
- ask pt to shrug shoulders and turn head against resistance
- palpate body of sternomastoid muscle while doing so

Question 9

how do you test cranial nerve 12?

Answer 9

hypoglossal nerve:
- ask pt to open mouth and observe tough for fasciculations
- push tongue into cheek against resistance

Question 10

what is Rinne’s test?

Answer 10

512Hz tuning fork held on mastoid until sound is no longer heard. it is then held near external acoustic meatus and sound should continue

Question 11

what is Weber’s test?

Answer 11

512Hz is held against forehead in the midline. vibrations should be perceived equally on both sides