Neuro Flashcards
1
Q
What can be seen in a general inspection of the patient in a cranial nerve exam? (4)
A
- General appearance
- Eye position (normal alignment/strabismus)
- Ptosis (unilateral/bilateral)
- Speech/voice abnormality (dysarthia)
2
Q
How is the olfactory nerve (CNI) tested?
A
Change in smell?
3
Q
What is tested to test the optic nerve (CNII) ?
A
- Pupils inspected
- Visual acuity + colour vision
- Pupillary reflexes
- Visual fields
- Fundoscopy
4
Q
What is inspected for in the pupils? (3)
A
- Size
- Shape
- Symmetry
5
Q
Common pupil signs and conditions associated? (2)
A
- Unilateral large and fixed pupil : CNIII palsy
- Unilateral small and reactive: Horner’s syndrome
6
Q
Neuro causes of decreased visual acuity (2)
A
- Optic nerve II pathology - optic neuritis
- Visual pathway lesion
7
Q
Difference between decreased visual acuity caused by papilloedema vs optic neuritis?
A
Papilloedema due to raised ICP doesn’t effect visual acuity until much later
8
Q
What pupillary reflexes are tested? (4)
A
- Direct pupillary reflex
- Consensual pupillary reflex
- Accomodation reflex
- Swinging light reflex
9
Q
What are the normal pupillary reflexes?
A
- Both pupils (direct and consensual) CONSTRICT in response to light
10
Q
How would an afferent pupil defect present? (CNII issue)
A
Light shone in effected nerve eye = no constriction in effected/contralateral
Light shone in contralateral pupil = constriction in both eyes
11
Q
How would an efferent pupil defect present? (CNIII issue) (2)
A
- One dilated pupil not responding to light in either eye (no direct/consensual reflex) = also points up and out
- Other uneffected pupil will constrict (consensual reflex) when light shone in affected eye
12
Q
What could an afferent pupil defect be caused by?
A
- Optic nerve defect
- Edinger-Westphal nucleus defect
13
Q
How is the swinging light test performed?
A
Move the pen torch rapidly between the two pupils, shining the light for three seconds in each eye.
14
Q
How can the swinging light test detect an afferent pupillary defect?
A
Dilation of the pupil when it should normally constrict
15
Q
How is the accommodation reflex tested? (3)
A
- Ask the patient to focus on a distant object
- Place your finger/object approximately 15cm in front of the eyes.
- Ask the patient to switch from looking at the distant object to the nearby finger/object
16
Q
What is normal accommodation reflex?
A
Convergence and constriction bilaterally
17
Q
What is a Marcus-Gunn pupil?
A
Ill sustained contraction of pupil in swinging light test
18
Q
What is a Marcus-Gunn pupil caused by?
A
Optic neuritis
19
Q
What does the accommodation reflex test?
A
CNIII/efferent pathway
20
Q
What charts are used to test colour vision?
A
Ishihara charts
21
Q
How are visual fields assessed? (8)
A
- Keep glasses on
- Eye level
- Focus on nose and not finger
- Ask patient to cover their left eye with left hand
- Cover your right eye with right hand (mirrors patient)
- Position your fingertip at each border of your visual field then wiggle slowly inwards to the centre
- Do for each quadrant
- Only move tip of finger
22
Q
Rare neuro cause of loss of red reflex?
A
Neuroblastoma
23
Q
How are nerves occulomotor (III) trochlear (IV) abducens (VI) assessed? (2)
A
- Note ptosis
- Drawing a H
- Checking for nystagmus
24
Q
Causes of ptosis (4)
A
- CN III pathology
- Horner’s syndrome
- Congenital/age
- Neuromuscular pathology - myasthenia
25
How are eye movements tested?
- Ask patient to fix on eye
- Ask patient to report any double vision
- Slowly draw Hs in front of each eye
- Pause at each point to detect nystagmus
26
What is nystagmus?
Flickering involuntary eye movements
27
What is detected in testing eye movements? (2)
- Nystagmus
| - Restriction
28
All eye muscles are innervated by the oculomotor nerve except which ones? What are their movements and what nerve innervates them instead?
SO4LR6
- Superior oblique: downwards and in
- Lateral rectus: lateral movement
29
How is the trigeminal nerve tested? (2)
- Light touch and pinprick sensation (sternum first for reference)
- Feel bulk of masseter and temporalis
- Jaw clench
- Reflexes (jaw jerk)
30
Branches of the trigeminal nerve and their areas of sensation? (3)
Forehead - ophthalmic branch (CNVi)
Cheeks - maxillary branch (CNVii)
Jaw - mandibular branch (CNViii)
31
What muscles are felt for bulk to test CN V and where are they? (2)
- Masseter (jaw)
| - Temporalis (temples)
32
How is the jaw jerk reflex tested?
- Ask patient to open mouth loosely
- Place finger horizontally across the chin
- Tap finger with a tendon hammer
33
Normal jaw jerk reflex
Slight closure of the jaw
34
Abnormal jaw jerk reflex and suggested pathology
Brisk complete closure of the jaw - upper motor CNV lesion
35
How is the facial nerve tested? (VII) (4)
- Inspection
- Facial movements
- Inspection of external auditory meatus
- Hearing/taste changes?
36
What is inspected when testing the facial nerve? (3)
- Forehead wrinkles
- Nasolabial folds
- Angles of the mouth
37
What are the facial movements for testing the facial nerve? And what is assessed? (5)
- Raise eyebrows : symmetry
- Close eyes: power
- Blow out cheeks: power
- Smiling: symmetry
- Close lips: power - each side
38
Why is the external auditory meatus inspected in testing the facial nerve?
Herpes zoster lesions – Ramsay Hunt syndrome
| Shingles causing lower motor lesion in CNV
39
Why are hearing changes relevant in testing the facial nerve?
CNV supplies stapedius - paralysis=hyperacusis (noise sensitivity)
40
Why are taste changes relevant in testing the facial nerve?
Supplies taste sensation to anterior 2/3 of tongue
41
What are the two aspects of testing the vestibulocochlear VIII nerve? (2)
- Hearing
| - Vestibular
42
What are the 3 hearing tests for testing the vestibulocochlear VIII nerve?
- Gross hearing
- Rhinne's test
- Weber's test
43
How is the test for gross hearing carried out? (5)
- Mouth 15cm from ear
- Whisper 99
- Mask ear not being tested by making rubbing sounds
- Ask them to repeat back
- If can hear, assess at 60cm
44
What size tuning fork is used to carry out Rhinne's/Weber's test?
512hz
45
How is Rhinne's test carried out? (4)
- Tap fork and put base on mastoid process (bony process)
- Ask if can hear (bone conduction) then to say when they stop hearing
- Move 1cm away from external auditory process (air conduction) : ask if can hear better?
- Do in other ear
46
What is a positive Rhine's test? And what 2 hearing states produce it?
Air conduction better than bone conduction
- Normal hearing
- Neurosensory hearing loss
47
Why does neurosensory hearing loss produce a positive Rhinne's test?
All hearing reduced, so air conduction still better than bone relatively
48
Why does conductive hearing loss produce a negative Rhinne's test?
Can't hear physically, so air conduction bad in affected ear
49
How is Weber's test carried out? (2)
- Place tuning fork in middle of forehead
| - Ask which ear its heard louder in
50
What is a normal Weber's test result?
Hearing equal on both sides
51
What would a conductive hearing loss produce in a Weber's test and why? (2)
Louder in affected ear
| - Bone conduction is better than air in that ear (not competing with ambient noise of room as can't hear it)
52
What would a neurosensory hearing loss produce in a Weber's test and why? (2)
Louder in normal air
| As hearing impulses not conducted in affected ear at all to brain
53
What are the two tests of the vestibular system? (2)
- Unterberger test
| - Head thrust
54
What reflex does the head thrust test test?
Vestibular-Ocular reflex
55
How is the unterberger test carried out? (2)
- Ask patient to march on the spot with arms outstretched and eyes closed
- Positive: patient rotates towards the side of the vestibular lesion
56
How is the head thrust test carried out to test for the vestibulocochlear VIII nerve? (5)
- Ask if neck pain?
- If not then hold head with one hand covering each ear
- Ask patient to look at nose
- Turn sharply to one side then the other
- Normal: fixation on nose maintained
57
What would the head thrust test in a vestibulocochlear loss of function patient result be? (2)
- Eyes will move in direction of the head (loss of fixation)
| - Corrective refixation saccade towards nose
58
What are the tests for the glossopharyneal IX and vagus X nerves? (4)
- Gag reflex (mention don't do)
- Uvula inspection (aah and symmetry)
- Cough
- Swallow
59
When assessing the glossopharyneal IX and vagus X nerves what are abnormal findings in the uvula?
- Deviation away from side of lesion
| - Aah: uvula observed better when moving upwards
60
What type of cough indicates a CNIX or CNV problem?
Bovine cough
61
What type of swallow indicates a CNIX or CNV problem? (2)
- Delayed
| - Coughing during
62
What are the tests for the XI accessory nerve? And what actions carry them out? (2)
- Trapezius power: ask patient to shrug shoulders against resistance
- Sternocleidomastoid power: ask patient to turn head against resistance (your hand on cheek)
63
A left weak sternocleidomastoid indicates a lesion on which side?
Right: contralateral control
64
How is the Hypoglossal XII nerve tested? (3)
- Tongue fasiculations and wasting
- Tongue deviation?
- Put finger on cheek, ask patient to push tongue against it
65
What side does a tongue deviate towards?
The side of the lesion
