Cranial nerve exam Flashcards
How would you test CN-I (olfactory)?
Have you noticed any changes in smell recently?
How would you test CN-II (optic)?
- Visual acuity
- Visual fields
- Pupillary reflexes
- Fundus
How would you test visual acuity?
“Do you wear glasses or contacts?”
“Have you had any problems with your vision lately?”
Snellen chart, ask pt to read sth covering one eye at a time
How would you test visual fields?
- Inattention: look at may nose, put your arms at both sides and wiggle one or two fingers (stroke)
- Visual field (ideally with a white hat pin)
“look at my nose, can you see my whole face”
Cover one eye at a time while also covering own opposite eye. Test all four corners for both eyes
How would you test pupillary reflexes?
Ask pt to concentrate on spot on the wall
Look for direct and consensual response
Swinging torch test !
What is RAPD?
Rapid afferent pupillary defect
Often due to optic neuritis secondary to MS
investigate with swinging torch test
How would you test the fundus?
“I would ideally like to examine the funds by ophthalmoscopy”
How would you test CN-III, CN-IV and CN-VI (oculomotor, trochlear, abducens)?
- Eye movements
2. Accommodation
What would abnormal position of eye indicate?
Oculomotor lesion
How would you test eye movements?
“Keep your head still and follow my finger”
“Let me know if you see double at any point”
H movement
What is ophthalmoplegia?
Paralysis of the extraocular muscles that control the movements of the eye
Can be seen when doing eye movement test
If there is diplopia during eye movement tests, what would you ask?
- Ask if image is separated horizontally or vertically
- Cover each eye in turn, which image disappears?
- Looking to the side: lateral image from affected side
- Looking down: lower image from affected side
- Looking up: upper image from affected side
How would you test for accommodation?
‘Keep looking at my finger”
Bring finger to nose of patient, pupils should constrict
How would you categorise the tests for CN-V (trigeminal)?
- Sensory
- Motor
- Reflexes
How would you test for sensory in CN-V (trigeminal)?
Ask patient to close eyes and say yes when you touch them
Go over:
- Ophthalmic division: above eyebrows
- Maxillary division: over zygoma
- Mandibular division: jaw
Do both sides feel the same?
How would you test for motor in CN-V (trigeminal)?
- Jaw opening against resistance
2. Jaw clenching: feel masseter and feel frontalis
How would you test for reflexes in CN-V (trigeminal)?
- Mention corneal rerflex (or cotton wool in nostril)
2. Jaw jerk
What is a minimal or absent jaw jerk indicative of? And a brisk one?
Minimal: normal
Brisk: UMN, stroke, tumour, MS
How would you categorise the tests for CN-VII (facial)?
- Facial tone
- Motor
- Sensory
How would you test for facial tone in CN-VII (facial)?
Look for reduced facial tone:
- Reduced wrinkling of forehead (LMN)
- Drooping of corner of mouth
- Flattening of nasolabial fold
How would you test for motor in CN-VII (facial)?
Raise eyebrows
Screw up eyes, and don’t let me open them
Puff out cheeks
Teethy smile
How would you test for sensory in CN-VII (facial)?
“Have you noticed any changes in taste (anterior 2/3 of tongue; chordates tympani)
“Are you troubled by loud noises?” (branch to stapedius)
How would you test for CN-VIII (vestibulocochlear)?
- Hearing: stroke tragus and look at ear. Whisper numbers on both sides
- Rinne and Weber test
How would you test for CN-IX, CN-X and CN-XII (glossopharyngeal, vagus, hypoglossal)?
- Bulbar function: say aaa and look at movement of uvula, speech, water swallowing
- Tongue: appearance and movement
