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The cranial nerve examination is often considered one of the most difficult OSCE stations, but with plenty of practice and some helpful acronyms along the way, you’ll be fine. The important thing to remember is that in an OSCE you’ll rarely be required to complete an entire cranial nerve exam in one station.  


Wash hands

Introduce yourself

Confirm patient details – name / DOB

Explain the examination  – I’m going to be testing the nerves that supply your face”

Gain consent

Position patient on a chair at eye level – approximately 1 arms length away

Ask if the patient currently has any pain.

Gather equipment
  • Pen torch
  • Snellen chart
  • Ishihara plates
  • Ophthalmoscope
  • Cotton wool
  • Neuro-tip
  • Tuning fork (512hz)
  • Glass of water
  • Mydriatic eye drops (if necessary)
General inspection

General appearance – comfortable at rest?

Obvious facial asymmetries?

Position of eyes – normal alignment / strabismus 

Ptosis – is this unilateral or bilateral?

Abnormality of speech or voice? – dysarthria 

Signs around the bed – e.g. hearing aid / glasses 

I – Olfactory nerve

Any change in sense of smell? “What was the last thing you remember smelling?”

With eyes closed, ask patient to identify various scents  e.g. coffee / vinegar 

II – Optic nerve

Size – normal size is approximately 2-4mm in diameter  (bright light)

Position – assess pupil alignment – misalignment noted in strabismus

  • Inspect pupils.
Visual acuity

1. Stand the patient at 6 metres from the Snellen chart.
2If patient normally uses distance glasses, ensure they wear them for the assessment.
3. Ask the patient to cover one eye & read to the lowest line they can manage.
4. Visual acuity is recorded as chart distance (numerator) over number of lowest line read (denominator).
5. Record the lowest line the patient was able to read (e.g. 6/6 which is equivalent to 20/20).
6. You can have the patient read through a pinhole to see if this improves vision.
7. Repeat above steps with the other eye.


If patient is unable to read top line at 6 metres (even with pinhole):

1. Reduce the distance to 3 metres from the Snellen chart.
2. Reduce the distance to 1 metre from the Snellen chart.
3. Assess if they can count the number of fingers you’re holding up.
4. Assess if they can see gross hand movement.
5. Assess if they can detect light from a pen torch shone into each each.
If the patient is unable to perceive light, this suggests they are blind.

  • Assess visual acuity.
Pupillary reflexes

Direct reflex– shine torch into eye – look for pupillary constriction in that eye

Consensual reflex – shine torch into eye  – look for pupillary constriction in opposite eye

Swinging light test– move light in from side of each eye rapidly – relative afferent pupillary defect (RAPD)


Accommodation reflex:

1. Ask patient to focus on a distant point (clock on a wall / light switch).

2. Place your finger/object approximately 15cm in front of the eyes.

3. Ask the patient to switch from looking at the distant object to the nearby finger / object.

4. Observe the pupils, you should see constriction & convergence bilaterally.

  • Assess direct & consensual pupillary reflexes.


Colour vision

Assess colour vision using Ishihara charts (unlikely to do this in an OSCE setting)







Visual fields


Sit directly facing the patient, approximately 1 metre away.



Visual inattention (visual neglect)

1. Ask patient to focus on your face & not move their head or eyes during the assessment.
2. Hold both arms out, with one hand in the upper right and the other in the upper left quadrant of your visual field.
3. Remind the patient to keep their head still & their eyes fixed on your face.
4.  Move one of your fingers (on only one hand) and ask the patient to point at the hand on which the finger is moving.
5. Move the finger on the left and right hand individually in whichever order you prefer.
6. Then move the finger of both hands simultaneously.
7. If patient only reports a finger on one of the hands moving (whilst both are moving simultaneously), it suggests the presence of visual neglect.

8. Repeat the process with your hands in the lower quadrants of vision.

Visual fields

1. Ask the patient to cover their left eye with their left hand.

2. You should cover your left eye and be staring directly at the patient (mirror the patient).

3. Ask patient to focus on your face & not move their head or eyes during the assessment.

4. Ask the patient to tell you when they can see your fingertip wiggling.

5. Outstretch your arms, ensuring they are situated at equal distance between yourself & the patient.

6. Position your fingertip at the outer border of one of the quadrants of your visual field.

7. Slowly bring your fingertip inwards, towards the centre of your visual field until the patient sees it.

8. Repeat this process for each quadrant – at 10 o’clock  /2 o’clock / 4 o’clock / 8 o’clock.

9. If you are able to see your fingertip but the patient cannot, this would suggest a reduced visual field.

10. Map out any visual field defects you detect.

11. Repeat the same assessment process on the other eye.

  • Assess visual inattention.


1. Darken the room.

2. The patient should have their pupils dilated with short-acting mydriatic eye drops.

3. Ask the patient to fixate on a distant object.


Assess for red reflex

1. Position yourself at a distance of around 30cm from the patient’s eyes.
2. Looking through the ophthalmoscope observe for a reddish / orange reflection in the pupil.

An absent red reflex may indicate the presence of cataract, or in rare circumstances neuroblastoma.


Move in closer & examine the eye with the fundoscope

Begin medially & assess the optic disc – colour / contour / cupping
Assess the retinal vesselscotton wool spots / AV nipping / neovascularization
Finally assess the maculaask to look directly into the light – drusen noted in macular degeneration

III, IV, VI – Oculomotor, Trochlear & Abducens nerves

Note any evidence of ptosis – oculomotor nerve pathology 

Eye movements

1. Ask the patient to keep their head still & follow your finger with their eyes.
2. Move your finger through the various axis of eye movement (“H” shape).

3. Ask the patient to report any double vision.

4. Observe for restriction of eye movement & note any nystagmus.


Cover test

1. Ask patient to focus on a target (e.g. your pen top).

2. Cover one of the patient’s eyes.


3. Observe the uncovered eye for movement:

  • No movement = normal response
  • Eye moves temporally = convergent squint
  • Eye moves nasally = divergent squint

4. Repeat the cover test on the other eye.

  • Assess eye movements using "H" test.
V – Trigeminal nerve

Assess light touch and pinprick sensation:

  • Forehead ophthalmic branch (V1)
  • Cheek – maxillary branch (V2)
  • Jaw – mandibular branch (V3)

Compare left to right for each branch.

Demonstrate sensation on patient’s sternum first, to ensure they understand what it should feel like.



1. Ask patient to clench their teeth whilst you feel the bulk of masseter & temporalis bilaterally.

2. Ask patient to open their mouth whilst you apply resistance under the jaw – note any deviation (jaw will deviate to side of lesion)


Jaw jerk:

  • Ask patient to open mouth loosely
  • Place your finger horizontally across the chin
  • Tap your finger with a tendon hammer
  • Normal = slight closure of the jaw
  • Abnormal = brisk complete closure of the jaw – UMN lesion


Corneal reflex:

  • Explain procedure & gain consent
  • Depress lower eyelid
  • Ask patient to look upwards
  • Touch edge of cornea using a wisp of cotton wool
  • Normal response = Direct & consensual blinking
  • Not usually required in an OSCE setting
  • Assess light touch sensation - Ophthalmic branch (V1)
VII – Facial nerve
Inspect the patient’s face at rest for asymmetry:

Forehead wrinkles 
Nasolabial folds
Angles of the mouth


Ask the patient to perform specific facial movements

Raised eyebrows – “raise your eyebrows as if you’re surprised” – note asymmetry

Closed eyes  “scrunch up your eyes & don’t let me open them” – assess power

Blown out cheeks“blow out your cheeks & don’t let me deflate them” – assess power

Smiling – “can you do a big smile for me?”note asymmetry 

Pursed lips – “can you attempt to whistle for me?” – note asymmetry

  • Raise eyebrows.
Other things to check…

Inspect external auditory meatus herpes zoster lesions – Bell’s Palsy

Any hearing changes? facial nerve supplies stapedius – paralysis results in hyperacusis

Any taste changes? – supplies taste sensation to the anterior 2/3 of the tongue 

  • Inspect external auditory meatus.
VIII – Vestibulocochlear  nerve
Gross hearing testing

Ask the patient if they have noticed a change in their hearing recently.

Assess each ear individually, standing behind the patient.

1. Explain to the patient that you’re going to say a word or number and you’d like them to repeat it back to you.

2. With your mouth approximately 15cm from the ear, whisper a number or word.

3. Mask the ear not being tested by rubbing the tragus.

4. Ask the patient to repeat the number or word back to you.

5. If the patient repeats the correct word or number, repeat the test at an arms length from the ear (normal hearing allows whispers to be perceived at 60cm).

6. Assess the other ear in the same way.

  • Assess hearing at approximately 15cm


Rinne’s test

1. Tap a 512HZ tuning fork & place at the external auditory meatus & ask the patient if they are able to hear it (air conduction)

2. Now move the tuning fork (whilst still vibrating), placing its base onto the mastoid process (bone conduction)

3. Ask the patient if the sound is louder in front of the ear (EAM) or behind it (mastoid process)

  • Normal = Air conduction > Bone conduction (Rinne’s positive)
  • Neural deafness = Air conduction > Bone conduction (both air & bone conduction reduced equally)
  • Conductive deafness = Bone conduction > Air conduction (Rinne’s negative)
  • Place tuning fork on the mastoid process.


Weber’s test

1. Tap a  512HZ tuning fork & place in the midline of the forehead.

2. Ask the patient where they can hear the sound:

  • Normal = sound is heard equally in both ears
  • Neural deafness = sound is heard louder on the side of the intact ear
  • Conductive deafness = sound is heard louder on the side of the affected ear
  • Place tuning fork in the midline of the forehead.


Vestibular testing – “turning test”

Ask patient to march on the spot with arms outstretched & eyes closed:

  • Normalpatient remains in the same position
  • Vestibular lesionpatient will turn toward the side of the lesion
  • Turning test - assessing for a vestibular lesion.
IX & X – Glossopharyngeal & Vagus nerves

Assess soft palate & uvula:

  • Symmetry – note any obvious deviation of the uvula
  • Ask patient to say “ahhhh” – observe uvula moving upwards – any deviation?

Gag reflexyou won’t do this in the OSCE, but just make sure you mention it
Ask patient to cough– damage to nerves IX & X can result in a bovine cough
Swallowask patient to take a sip of water – note any coughing / delayed swallow

  • Assess soft palate and uvula.
XI – Accessory nerve

Ask patient to shrug shoulders & resist you pushing downtrapezius 

Ask patient to turn head to one side & resist you pushing it to the other sternocleidomastoid

Note any weakness.

  • Assess Trapezius strength.
XII – Hypoglossal nerve

1. Inspect tongue for wasting & fasciculation at rest.
2. Ask patient to protrude tongue –
any deviation?
3. Place your finger on the patient’s cheek & ask to push their tongue against it – 
assess power

  • Inspect tongue at rest for fasciculations.
To complete the examination

Thank patient

Wash hands

Summarise findings


Say you would…

Perform further testing of any nerves that had abnormal results.

Carry out a full neurological examination of the upper & lower limbs .