Cranial Nerve Testing

Question 1

CN I - Olfactory

Answer 1

Check nasal patency.

Sense of smell in both nostrils (2 different smells).

Question 2

CN II - Optic Pt. 1

Answer 2

Visual acuity (OD, OS, OU)

Rosenbaum Chart

Question 3

CN II - Optic Pt. 2

Answer 3

Confrontation

Wiggle fingers

Abnormal - check nasal fields

Question 4

CN II - Optic + CN III - Oculomotor

Answer 4

Size + shape of pupil and reaction to light (consensual and direct).

Question 5

CN III - Oculomotor + CN IV - Trochlear + CN VI - Abducens

Answer 5

Extra-ocular movements (all quadrants of patient’s gaze)

Convergence

Question 6

CN V - Trigeminal (Motor)

Answer 6

Temporal and masseter muscles (note strength of contraction).

Question 7

CN V - Trigeminal (Sensory)

Answer 7

Light touch on forehead, cheeks and jaw (cotton).

Question 8

CN VII - Facial

Answer 8

Raise eyebrows, frown, close eyes, show teeth, smile, puff cheeks, close eyes (cannot open).

Observe at rest and during performance.

Question 9

CN VIII - Acoustic (Vestibulocochlear)

Answer 9

Assess hearing with whispered voice.

Question 10

CN IX - Glossopharyngeal + CN X Vagal

Answer 10

Voice quality + movement of soft palate.

Listen to voice, open mouth and say “ah”. Observe palate and pharynx movement.

Question 11

CN XI - Spinal Accessory

Answer 11

Shrug shoulders and turn head.

Place hands on shoulders and ask him to shrug.

Place hands on check and turn head.

Question 12

CN XII - Hypoglossal

Answer 12

Observe tongue for fasciculations, symmetry, deviation, movement and strength.

Speech, observe tongue, stick tongue out, tongue side to side, tongue to cheek.

Question 13

Cranial Nerve Mnemonic

Answer 13

Oh, Oh, Oh to touch and feel very good velvet. Such heaven!

1. Olfactory
2. Optic
3. Oculomotor
4. Trochlear
5. Trigeminal
6. Abducens
7. Facial
8. Vestibulocochlear (Acoustic)
9. Glossopharyngeal
10. Vagal
11. Spinal Accessory
12. Hypoglossal