Cranial Nerves Exam Flashcards
General inspection of patient
Patient: - calm and comfortable at rest - any facial abnormalities, - position of eyes (normal alignment or strabismus) - ptosis (unilateral promises bilateral) - abnormality of speech or voice (dysarthria) Around bed: - hearing aid - glasses
Olfactory nerve
- have you noticed any chance in your smell
- ideally I would like to test the sense of smell using smelling salts, one nostril at a time
Optic nerve
What are the different things you test for?
Acuity Fields Reflexes I attention Colour Accommodation Offer fundoscopy
How do you test the patients acuity?
- ask pt If they wear glasses
- offer Snellen chart (pt 6m away and should wear their glasses. Cover one eye and read lowest line possible. Numerator is distance away, denominators is lowest line rad)
How do you test the visual fields?
- cover same eye as patient mirroring them
- compare their visual field to your own
- wiggle fingertip and move hand inwards asking pt to say yes when they can see your finger
- test all 4 quadrants for both eyes
Which reflexes do you test?
- inspect pupils looking for size, roundness and symmetry
- direct and consensual reflexes in both eyes
- sluggish reaction or lack of constriction = pathology (drugs, brainstem, optic nerve)
- lack of normal consensual reflex = damage to optic nerve, damage to EW nucleus
- swinging light test (move torch rapidly between both pupils). May detect RAPD
What is a RAPD?
Relative afferent pupillary defect
- caused by damage of tract between optic nerve and optic chiasm (optic neuritis in MS)
- RAPD detected by paradoxical dilatation it affected pupil when light is shining into it (should constrict)
How do you test for neglect?
- ask pt to report which fingers you are moving whilst pt looks straight ahead
- try left, right, then both sides together
How do you test colour?
Ask to use an Ishihara colour chart
How do you test for accommodation?
- ask pt to focus on distant object and place your finger 15cm from front of their eyes
- ask pt to switch from looking at distant object to looking at finger
- CONSTRICTION AND CONVERGENCE BILATERALLY
What else should you offer?
Fundoscopy
How do you test for oculomotor, trochlear and abducens nerves?
- ptosis (oculomotor nerve palsy)
- ask pt to tell you if they have any blurriness or double vision during test
- Eye movements: H TEST
How do you test the trigeminal nerve?
SENSORY:
- light touch with cotton wool on areas of branches
MOTOR:
- clench teeth while feel masseter and temporalis
- ask pt to open their mouth whilst applying resistance under their jaw (jaw will deviate to side of lesion)
(Trigeminal neuralgia, Hermes zoster, acoustic neuroma)
REFLEXES:
- jaw jerk
- corneal reflex
How do you test the facial nerve?
- ask pt if they have noticed any changes in sense of taste (sensation for anterior 2/3rds of tongue)
- inspection: forehead wrinkles, nasolabial folds, angles of mouth
Movements:
- raise eyebrows against resistance
- scrunch up eyes against resistance
- blow our cheeks against resistance
- simile and show me your teeth
How do UMN and LMN lesions affect facial nerve?
UMN: forehead sparing (stroke, tumour)
LMN: Bell’s palsy, otitis media, heroes zoster
