cranial nerves

Question 1

Cranial Nerve I

Answer 1

Olfactory Nerve
(sense of smell)

Question 2

How to test Cranial Nerve I

Answer 2

1. Ask the pt if they’ve noticed a change in smell.
2. Test with aromatic substances.

Question 3

Cranial Nerve II

Answer 3

Optic Nerve
(sight)

Question 4

How to test Cranial Nerve II

Answer 4

1. Ask the pt about their sight.
2. Check visual acuity using the Snellen Chart and pupillary reactions to light.

Question 5

Cranial Nerve III

Answer 5

Oculomotor -
motor to the extraocular muscles.

Question 6

Cranial Nerve IV

Answer 6

Trochlear Nerve -
Motor to the superior oblique muscles.

Question 7

Cranial Nerve V

Answer 7

Trigeminal Nerve -
sensory to the facial skin and oral mucosa, motor to the muscles of mastication.

V1 - OPTHALMIC
V2 - MAXILLARY
V3 - MANDIBULAR

Question 8

How to test Cranial Nerve V

Answer 8

Check if the sensation is normal over all 3 divisions:
1. Does the pt have a normal corneal reflex.
2. Can they clench their jaw.

Question 9

How to test Cranial Nerves III, IV and VI

Answer 9

Test the pts eye movement by asking them to look in different directions.

Question 10

Cranial Nerve VI

Answer 10

Abducens -
motor to the lateral rectus muscle.

Question 11

Cranial Nerve VII

Answer 11

Facial Nerve -
a. motor to the muscles of facial expression
b. sensory to the external acoustic meatus
c. involved in taste sensation

Question 12

How to test Cranial Nerve VII

Answer 12

Can the pt pout, smile, wrinkle their forehead or raise eyebrows.
(nerve supply to the forehead is bilateral so this may not be a good indicator).

Question 13

Cranial Nerve VIII

Answer 13

Vestibulocochlear -
hearing and balance.

Question 14

How to test Cranial Nerve VIII

Answer 14

1. Can the pt hear normally.
2. Block one ear and get the pt to tell you what number you said.

Question 15

Cranial Nerve IX

Answer 15

Glossopharyngeal -
supplies the stylopharyngeus and taste in the posterior 1/3 of the tongue.

Question 16

How to test Cranial Nerve IX

Answer 16

Ask the pt to say aaaah and look for any vulval deviation.
If damage is present, there will also be no gag reflex.

Question 17

Cranial X

Answer 17

Vagus -
neck, thorax and abdomen.

Question 18

How to test Cranial Nerve X

Answer 18

1. Look for deviation in the vulva.
2. Check gag reflex although this is not always reliable and uncomfortable.

Question 19

Cranial Nerve XI

Answer 19

Accessory -
innervates sternocleidomastoid and trapezius.

Question 20

How to test Cranial Nerve XI

Answer 20

Ask the pt to shrug their shoulders.

Question 21

Cranial Nerve XII

Answer 21

Hypoglossal -
motor to the tongue.

Question 22

How to test Cranial Nerve XII

Answer 22

1. Ask the pt to protrude their tongue.
2. Look to see if it is symmetrical in both movement and bulk.