CN Examination

Question 1

Equipment

Answer 1

• Pen torch
• Snellen chart
• Ishihara plates
• Ophthalmoscope and mydriatic eye drops (if necessary)
• Cotton wool
• Neuro-tip
• Tuning fork (512hz) or 128
• Glass of water

Question 2

General inspection

Answer 2

• Speech abnormalities:may indicate glossopharyngeal or vagus nerve pathology.
• Facial asymmetry:suggestive of facial nerve palsy.
• Eyelid abnormalities:ptosis may indicate oculomotor nerve pathology.
• Pupillary abnormalities:mydriasis occurs in oculomotor nerve palsy.
• Strabismus:may indicate oculomotor, trochlear or abducens nerve palsy.

Question 3

CN1

Answer 3

• Ask patient if any recent change in sense of smell?
• Use different well known odours - e.g. soap or coffee
• Test each nostril separately

Question 4

CN3/4/6

Answer 4

• Ask patient to follow finger or pin and assess all areas of eye movement. Looking for fluid eye movement and ability top look in all directions.
• Ask pt if they are experiencing any double vision before starting and ask them to tell you if they experience any during the examination.
• Any problem except from moving eye down and in or directly lateral is a 3rd nerve palsy.

Problem with the Superior Oblique. Cannot move eye down and medially

Problem with the lateral rectus. - cannot move eye laterally.

LO4SR6

Question 5

CN2

Answer 5

• Snellen chart for visual acuity
• Ask if they wear glasses, long sighted glasses should be worn during Snellen.
• If Snellen unavailable, use a magazine or book and assess different font sizes.
• Test visual fields - 4 quadrants and ask to say which finger is moving.
• Cover your opposite eye and ask the patient to say when they see the finger that is moving more centrally.
• Test for inattention, ask to stare at something in the distance and then something closer
• Test direct and consensual light reflexes - look for constriction in both pupils.
• Ask patient to follow finger and assess which is moving.
• Test colour vision using ischiara chart and opthalmoscopy.

Question 6

CN5

Answer 6

• Ask patient to clench jaw - feel for contraction of master muscle and temporals under the jaw.
• Sensation of face with cotton bud in all 3 areas
• Assess pain with prick test
• Offer to assess temperature
• Offer to assess corneal reflex and jaw jerk reflex

Question 7

CN7

Answer 7

• Raise eyebrows - temporal
• Scrunch eyes - zygomatic
• Blow out cheeks - Buccal
• Show teeth and whistle - mandibular
• Stick chin forward - cervical
• Ask patient to relax between tests.

Question 8

CN8

Answer 8

• Whisper at full arms length a number and ask pt to repeat, and move further away
• Cover contralateral ear.
• Repeat on both sides.
• Offer to assess balance - ask pt to march on the spot - pt will turn towards the site of the lesion.
• Perform rinnie and webers test

Question 9

CN9/10

Answer 9

• Please can you cough - checking for bovine cough
• Please can you take a sip of water and swallow
• Ask pt to open mouth and say ahhh to look for uvula deviation
• Offer to test gag reflex

Question 10

CN11

Answer 10

• Ask pt to shrug shoulders against resistance
• Ask pt to put chin on left shoulder and then to right shoulder against resistance

Question 11

CN12

Answer 11

• Open mouth - check for any tongue fasciculations
• Ask pt to stick out tongue - inspect for wasting or deviation
• Ask pt to push tongue into cheek and resist movement from outside.