cranial nerves Flashcards
Cranial Nerve I
Olfactory Nerve
(sense of smell)
How to test Cranial Nerve I
- Ask the pt if they’ve noticed a change in smell.
- Test with aromatic substances.
Cranial Nerve II
Optic Nerve
(sight)
How to test Cranial Nerve II
- Ask the pt about their sight.
- Check visual acuity using the Snellen Chart and pupillary reactions to light.
Cranial Nerve III
Oculomotor -
motor to the extraocular muscles.
Cranial Nerve IV
Trochlear Nerve -
Motor to the superior oblique muscles.
Cranial Nerve V
Trigeminal Nerve -
sensory to the facial skin and oral mucosa, motor to the muscles of mastication.
V1 - OPTHALMIC
V2 - MAXILLARY
V3 - MANDIBULAR
How to test Cranial Nerve V
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.
How to test Cranial Nerves III, IV and VI
Test the pts eye movement by asking them to look in different directions.
Cranial Nerve VI
Abducens -
motor to the lateral rectus muscle.
Cranial Nerve VII
Facial Nerve -
a. motor to the muscles of facial expression
b. sensory to the external acoustic meatus
c. involved in taste sensation
How to test Cranial Nerve VII
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).
Cranial Nerve VIII
Vestibulocochlear -
hearing and balance.
How to test Cranial Nerve VIII
- Can the pt hear normally.
- Block one ear and get the pt to tell you what number you said.
Cranial Nerve IX
Glossopharyngeal -
supplies the stylopharyngeus and taste in the posterior 1/3 of the tongue.
How to test Cranial Nerve IX
Ask the pt to say aaaah and look for any vulval deviation.
If damage is present, there will also be no gag reflex.
Cranial X
Vagus -
neck, thorax and abdomen.
How to test Cranial Nerve X
- Look for deviation in the vulva.
- Check gag reflex although this is not always reliable and uncomfortable.
Cranial Nerve XI
Accessory -
innervates sternocleidomastoid and trapezius.
How to test Cranial Nerve XI
Ask the pt to shrug their shoulders.
Cranial Nerve XII
Hypoglossal -
motor to the tongue.
How to test Cranial Nerve XII
- Ask the pt to protrude their tongue.
- Look to see if it is symmetrical in both movement and bulk.