Cranial Nerve Examination

Question 1

What are the 12 cranial nerves?

Answer 1

I: olfactory

II: optic

III: oculomotor

IV: trochlear

V: trigeminal

VI: abducens

VII: facial

VIII: vestibulocochlear

IX: glossopharyngeal

X: vagus

XI: accessory

XII: hypoglossal

Question 2

How are cranial nerves I and II assessed?

Answer 2

Ask about change in smell or taste

Perform fundoscopy

VA: handheld Snellen chart, pinhole correction if less than 6/6

VF: use fingers (or red hat-pin if you have one), test each quadrant

Question 3

How are cranial nerves (II), III, IV and VI assessed?

Answer 3

Inspect for ptosis, anisocoria (unequal pupil size)

Pupillary light reflex (direct and consensual, RAPD)

Convergence and accommodation reflex

Smooth pursuit eye movements

Question 4

Describe the pathway involved in the pupillary light reflex

Answer 4

Afferent: II

Efferent: III

Question 5

Describe the EOMs used over the full range of eye movements

Answer 5

Question 6

How are cranial nerves V and VII assessed?

Answer 6

Facial sensation: light touch and pain in all 3 divisions

Muscles of mastication: temporalis, masseter

Corneal reflex

Muscles of facial expression: wrinkle forehead, close eyes, smile (show teeth), puff cheeks out

Question 7

Describe the pathway involved in the corneal reflex

Answer 7

Afferent: V

Efferent: VII

Question 8

How are cranial nerves VIII-XII assessed?

Answer 8

Auditory acuity: whispered numbers

Rinne and Weber tests

Palatal elevation

(Gag reflex: omit unless there is a specific reason to test it)

Tongue protrusion

Spinal accessory muscles: SCM, trapezius