Cranial Nerves for FRACP

  1. Note the stem (important to commit to memory)
  2. Walk into room
  3. Wash hands
  4. Introduce yourself to the patient
    1. Hello. My name is Dr Nanayakkara, thank you for letting me examine your (vision, face etc)
  5. Place briefcase and open it up 
  6. Set-up room
  7. Position patient sitting at edge of bed if tolerated
  8. Expose patient to see shoulders and neck
  9. Step back and examine patient from front and from sides, if glasses are on table pick them up and make a show that you recognised them, examine behind ear for cochlear implants
    1. Acromegalic features
    2. craniotomy scars
    3. neurofibromas
    4. myotonic facies
  10. Cranial nerve 1
    1. Look at nose
    2. Ask to test for anosmia
  11. Cranial nerve 2 - 6
    1. If patient has glasses ask them to put them on
    2. Test visual acuity
      1. Ask patient if they can see the whole face
      2. using two hand held snellen charts
        1. aim of this part of the exercise is to make sure that the patient is not blind or near-blind in one or both eyes. Subtle abnormalities of visual acuity are not of concern
        2. Ask the patient to read the lowest line that they see
    3. Test visual fields
      1. Peripheral fields are tested by sitting in front of patient, asking the patient to look at your eyes. Then place hands in two upper quadrants. Tell them that you will move your fingers on one hand or the other, and sometimes both. Ask them to point to the hand whose fingers are moving
        1. Can detect homonymous hemianopia and visual neglect
        2. kinetic red boundary testing: the patient is asked to report when the colour red first apears in a mving target as it moves inward from the periphery
      2. Check blindspot
        1. It should be around the centre of the field of vision for both eyes
    4. Ask to perform fundoscopy
      1. If asked to, then make sure the lights are dimmed, use a narrow beam initially and a low light strength
    5. Test pupillary reflex by asking patient to fixate their gaze on the wall opposite
    6. Test for afferent pupillary defect
      1. noting for marcus gunn pupil, whereby when the light hits the impaired eye it abnormally dilates (as it is recovering from the previous pupillary constriction)
    7. Test the accomodation reflex
      1. Holmes-addie pupil: tonically dilated pupil that shows sluggish response to light but greater constriction with accomodation
    8. Test pursuit (and nystagmus) and at same time do cover test if diplopia occurs
      1. Trace a large H sign - this should be smooth, if it is jerky then this may give evidence to a cerebellar disorder
      2. Cover test - ask the patient when they see double. Ask them if they see the images side by side (VI) or on top of each other (III or IV)
    9. Test voluntary gaze
      1. Ask to look left, then right
      2. Ask to look up, then down
      3. Voluntary vertical saccades are impaired in progressive supranuclear palsy
    10. Test saccades by holding two thumbs side by side, ask them to look at the thumb that is moving
      1. In cerebellar syndromes the eyes may overshoot the target (ocular dysmetria)
      2. In parkinsons disease the patient may go from one eye to the other in a series of steps - eg parkinsons disease
  12. Cranial nerve 5 and 7
    1. Test sensation in V1, V2 and V3 dermatomes of the trigeminal nerve
    2. Test jaw opening - asking the patient to open it and don't let you close it
    3. Palpate the masseter muscles when clenching teeth
    4. Test jaw jerk reflex (CN V)
    5. Ask to test corneal reflex (Sensory through V, motor through VII)
    6. Ask to test taste in anterior two thirds of tongue (Sensory VII)
    7. Test motor of face
      1. Raise your eyebrows - make sure you palpate the forehead furrows (frontalis)
      2. Close your eyes tightly, dont let me open it (obicularis occuli)
      3. Show me your teeth - compare nasolabial folds
      4. Blow the cheeks out
  13. Cranial nerve 8
    1. Examine pinna, behind ear (vesicles of ramsy-hunt syndrome), external auditory canal
    2. Test hearing
      1. occlude one ear then whisper 68 (high frequency) and 100 (low frequency), asking patient to repeat back to you
    3. Rinne's test, using a 256Hz tuning fork on mastoid then over ear canal (should be louder over ear canal unless their is conductive deafness)
    4. Webbers test, vibrating 256Hz tuning fork on centre of forehead, ask in which ear the noise is heard best. If conductive loss then localises to the ear, sensorineural loss localises to the contralateral ear
  14. Cranial nerves 9, 10, 12
    1. Ask to assess the gag reflex (Cranial nerve 9 and 10)
    2. Check for palatal elevation (CN 10)
      1. Say 'ah', --> the palate and uvula are pulled away from the weekened side
    3. Ask to poke tongue out
      1. inspect for fasciculation's and wasting
      2. tongue deviates to the affected side upon voluntary protrusion (CN XII - hypoglossal)
  15. Cranial nerve XI
    1. Assess and test power of trapezius and sternomastoid muscles
    2. Palpate the sternomastoid muscles as a show to the examiners
  16. Cover and thank the patient, and ask to present your findings​