Cranial nerve examination

Question 1

How do you test the olfactory nerve (I)?

Answer 1

Using scents

Question 2

How do you test the optic nerve (II)?

Answer 2

Visual acuity - testing each eye separately (looking at Snellen chart)
Visual fields - cover opposite eye to patients, bring test object from outside of visual field into visual field
Testing for inattention/visual extinction - waggling fingers at edge of visual field, point to which is moving
Testing for direct and consensual light reflexes
Testing for accommodation
Ophthalmoscopy

Question 3

How do you test the occulomotor (III), trochlear (IV), and abducens (VI) nerves?

Answer 3

Follow finger in H shape

Question 4

How do you test the trigeminal nerve (v)?

Answer 4

Test sensation to skin supplying ophthalmic, maxillary, and mandibular nerves
Test motor component of trigeminal nerve - clench teeth, palpate contraction of masseter and temporalis muscles, open mouth against resistance looking for jaw deviation, jaw jerk

Question 5

How do you test the facial nerve (VII)?

Answer 5

Screw up eyes and not let them be opened
Puff out cheeks
Raised eyebrows
Purse lips
Show teeth

Question 6

How do you test the vestibulocochlear nerve (VIII)?

Answer 6

Cover opposite ear with hand and whisper number to patient

If abnormality Rinnes and Weber’s tests

Question 7

How do you test the glossopharyngeal (IX) and vagus (X) nerves?

Answer 7

Open mouth wide and assess uvula
Uvula will deviate away from side of palsy if say ahh
Ask them to cough - non-explosive suggests vagal palsy
Note hoarseness of voice

Question 8

How do you test the accessory nerve (XI)?

Answer 8

Test trapezius by asking patient to shrug shoulders against resistance
Turn head against resistance

Question 9

How do you test the hypoglossal nerve (XII)?

Answer 9

Ask patient to open mouth and observe tongue at rest for fasciculations
Protrude tongue and note deviation