Cranial Nerves

Question 1

CN I exam?

Answer 1

History of chance in sensation of smell
Use odourants known to patient (OFFER scented bottles)

OLFACTORY

Question 2

CN II exam?

Answer 2

Do you have glasses or contacts? Any changes in vision?
OFFER - Stellen’s chart (for acuity), Ishiharo plate (for colour), Fundoscopy.
Visual field confirmation test
Direct and consensual pupillary reflex

Question 3

CN III, IV + VI exam?

Answer 3

1. Motor - (CN III, IV + VI) H test for eye movements

(2. Parasympathetic - assessed by pupillary reflexes - for CN III)

Question 4

CN V exam?

Answer 4

1. Sensory - assess light touch (V1, V2 + V3 areas of face; opthalmic, maxillary, mandibular)
2. Motor - assess the muscles of mastication

(3. Corneal reflex and jaw jerk reflexes - OFFER)

TRIGEMINAL

Question 5

CN VII exam?

Answer 5

Any changes in taste?
1. Motor - facial muscles - assess facial muscle actions

OFFER (2. Taste - tongue anterior 2/3 - not tested)
OFFER (3. Parasympathetic - submandibular, sublingual and lacrimal glands - not tested)

FACIAL

Question 6

CN VIII exam?

Answer 6

any changes in hearing or balance?

1. Cochlear part - assess hearing (whisper, Rinne and Weber tests)

OFFER (2. Vestibular part - not tested)

VESTIBULO COCHLEAR

Question 7

CN IX exam?

Answer 7

Change in taste? Offer salt water ideally
Open mouth, stick tongue out

OFFER (General sensory - post 1/3 of tongue - assessed by ‘gag’ reflex)

GLOSSOPHARYNGEAL

Question 8

CN X exam?

Answer 8

Change in taste?
UVULA - say aaaa, should pull upwards. If deviates, will deviate away from side of lesion.
OFFER cough and swallow
1. Motor - assess action of soft palate

VAGUS

Question 9

CN XI exam?

Answer 9

1. Spinal accessory - motor - assess the strength of sternocleidomastoid and trapezius
2. Cranial accessory - motor - pharyngeal and laryngeal muscles - assessed with vagus

Neck muscles - place hand on face, look towards hand.
Trapezius - push shoulders against hand.
ACCESSORY

Question 10

CN XII exam?

Answer 10

Motor - tongue (test protrusion)
Stick tongue out. If deviates, will point towards side of lesion.
Place hand on cheek. Ask to push hand with tongue.
HYPOGLOSSAL

Question 11

Special tests?

Answer 11

1. Ophthalmoscopy
2. Otoscopy

Question 12

Movements exam?

Answer 12

1. Head - atlanto-axial and atlanto-occipital joints
2. Cervical and thoracocolumbar spine
3. TM joint and mandible (lower jaw)

Question 13

Palpation?

Answer 13

1. Bone/cartilage in head, neck and spine
2. TMJ, cricothyroid space
3. Lymph nodes

Question 14

Arterial pulses?

Answer 14

Carotid
Superficial temporal
Subclavian arteries

Question 15

Assessing JVP?

Question 16

V1, 2 + 3 areas?

Question 17

Muscles of mastication assessment?

Question 18

Facial muscle actions?

Answer 18

Raise eyebrows
Screw eyes - don’t let me open them
Puff out cheeks
Smile with teeth
Purse lips

Question 19

Whisper, Rinne and Weber test?

Answer 19

Whisper - rub fingers in one ear and say number in the other
Rinne - air vs bone - mastoid process and in front of ear
Weber - on forehead - is it same in both ears

Question 20

Sternocleidomastoid and trapezius assessment?

Answer 20

Shrug shoulders against force
Turn face against my hand each side

Question 21

Tongue protrusion assessment?

Answer 21

Look for deviation, wasting, fasciculation
Power - push tongue against cheek against force
Test words - “British Constitution”

Question 22

Weber test results?

Answer 22

Louder in affected ear - conductive hearing loss
Louder in healthy ear - sensorineural hearing loss

Question 23

Rinne’s test results?

Answer 23

Air>bone - normal
Bone>ear - conductive hearing loss

Question 24

What to offer for CN II?

Answer 24

Stellen’s chart
Ishiharo plate
Fundoscopy

Question 25

Visual field confirmation test?

Answer 25

Cover same eye, look at my nose, whittle fingers and say yes when see it move

Question 26

Direct and consensual pupillary reflexes?

Answer 26

Light, hold hand in between eyes, look for direct and consensual. Look at both eyes. Make obvious which eye looking at. Then do swinging light test

Question 27

H test?

Answer 27

For CN III, IV + VI Let me know if you see any pain or blurring/double vision *test for nystagmus*

Question 28

3rd nerve palsy?

Answer 28

Eye looks down and out

Question 29

4th nerve palsy?

Answer 29

Superior oblique bad, unable to look down and inwards

Question 30

6th nerve palsy?

Answer 30

Eye can’t abduct

Question 31

How to test motor CN V?

Answer 31

Maseter - hold jaw whilst they clench jaw Hold jaw whilst touching temporalis muscles Open mouth against resistance

Question 32

Offer for trigeminal?

Answer 32

Jaw jerk Cornea reflex

Question 33

Facial nerve motor tests?

Answer 33

Raise eyebrows Close eyes (against resistance) Puff out cheeks (against resistance) Smile with teeth Grimace

Question 34

Offer for facial nerve?

Answer 34

Taste test - ideally with salt water

Question 35

Frequency of hearing fork?

Answer 35

512 hz

Question 36

Rinne test interpretation?

Answer 36

Conductive hearing loss - Rinne louder on bone than ear Sensorineural - Rinne the same

Question 37

Weber test interpretation?

Answer 37

Conductive - amplifies Weber in bad ear than normal ear Sensorineural - amplifies Weber in good ear