Disorders of Cranial Nerves Flashcards
(93 cards)
1
Q
Name the 12 cranial nerves in order.
A
I Olfactory II Optic III Oculomotor IV Trochlear V Trigeminal VI Abducens VII Facial VIII Vestibulocochlear IX Glossopharyngeal X Vagus XI Accessory XII Hypoglossal
2
Q
What are the 4 classifications of functions that cranial nerves have?
A
- Special senses
- Ordinary sensation
- Control of muscle activity
- Autonomic functions
3
Q
What cranial nerves are involved in the special senses?
A
I (olfaction)
II (vision)
VII, IX, X (taste)
VIII (hearing and balance)
4
Q
Ordinary sensation is mainly by which cranial nerve?
A
V
5
Q
What cranial nerves are responsible for ordinary sensation of the ear?
A
VII and IX
6
Q
What cranial nerves are involved in control of muscle activity?
A
III IV V VI VII X XI
7
Q
Which cranial nerves control the ocular muscles?
A
III
IV
VI
8
Q
Which cranial nerve controls the muscles of mastication?
A
V
9
Q
Which cranial nerve controls the muscles of facial expression?
A
VII
10
Q
Which cranial nerve controls the muscles of the larynx and pharynx?
A
Mainly X
11
Q
Which cranial nerve controls the sternocleidomastoid and trapezius muscles?
A
XI
12
Q
What cranial nerves have parasympathetic components?
A
III
VII
IX
X
13
Q
Which cranial nerves is responsible for pupillary constriction?
A
III
14
Q
Which cranial nerve is responsible for lacrimation?
A
VII
15
Q
Which cranial nerve is responsible for salivation by the submandibular and sublingual glands?
A
VII
16
Q
Which cranial nerve is responsible for salivation by the parotid gland?
A
IX
17
Q
Which cranial nerve is responsible for input to organs in the thorax and abdomen?
A
X
18
Q
I
What do we test?
A
Loss of smell
-Unilateral or bilateral
19
Q
II
What do we test?
A
- Visual acuity
- Visual fields
- Pupillary reactions
- Fundoscopy
- Colour vision
20
Q
III, IV, VI
What do we test?
A
- Any evidence of ptosis?
- Pupil of equal size?
- Pupillary reactions
- Eye movements – vertical and horizontal
21
Q
V
What do we test?
A
- Sensation in the ophthalmic, maxillary and mandibular divisions
- Power in the muscles of mastication
- Corneal reflex
- Jaw jerk
22
Q
VII
What do we test?
A
- Muscles of facial expression
- Corneal reflex
- Taste
23
Q
VIII
What do we test?
A
- Hearing using Rinne’s and Weber’s tests
- Vestibular function using Dix-Hallpike manoevre and Untenberger’s test
24
Q
IX, X
What do we test?
A
- Movement of the palate
- Gag reflex
- Quality of speech
- Quality of cough
25
XI
| What do we test?
Head turning and shoulder shrugging
26
XII
| What do we test?
Appearance, movement and power of tongue
27
Which cranial nerve is responsible for the afferent pupillary light reaction?
II
28
Which cranial nerve is responsible for the efferent pupillary light reaction?
III
29
Which cranial nerve is responsible for the afferent corneal reflex?
V
30
Which cranial nerve is responsible for the efferent corneal reflex?
VII
31
Which cranial nerve is responsible for the afferent jaw jerk?
V
32
Which cranial nerve is responsible for the efferent jaw jerk?
V
33
Which cranial nerve is responsible for the afferent gag reflex?
IX
34
Which cranial nerve is responsible for the efferent gag reflex?
X
35
Where does the III nuclei lie?
Mid-brain
36
Where does the V nuclei lie?
Pons
37
Where does the X nuclei lie?
Medulla
38
Where does the IV nuclei lie?
Mid-brain
39
Where does the XII nuclei lie?
Medulla
40
Where does the VI nuclei lie?
Pons
41
Where does the IX nuclei lie?
Medulla
42
Where does the XI nuclei lie?
Medulla
43
Where does the VII nuclei lie?
Pons
44
Where does the VIII nuclei lie?
Pontomedullary junction
45
What may an unusual combination of cranial nerve signs suggest?
Chronic or malignant meningitis
46
What may pure motor cranial nerve signs suggest?
Myasthenia gravis
47
Where may there be a problem if there is bilateral III signs?
Midbrain
48
Where may there be a problem if there are III, IV and VI signs?
Superior orbital fissure
49
Where may there be a problem if there is VI and VII signs?
Pons
50
Where may there be a problem if there is V and VIII signs?
Cerebellopontine angle
51
When may eye movement disorder, facial weakness and difficulty swallowing occur other than in cranial nerve lesions?
After stroke
52
When may double vision occur other than in cranial nerve lesions?
Myasthenia or thyroid eye disease
53
How can cranial nerves be damaged within the brain?
- Ischaemia
| - Tumour
54
How can cranial nerves be damaged crossing the sub-arachnoid space?
Meningitis
55
How can cranial nerves be damaged outside the skull?
-Skull tumours
56
What is optic neuritis?
Demyelination within the optic nerve
57
What are the signs and symptoms of optic neuritis?
- Monocular visual loss
- Pain on eye movement
- Reduced visual acuity
- Reduced colour vision
- Optic disc may be swollen
58
What is optic neuritis often associated with?
MS
59
What does parasympathetic innervation of the pupil result in?
Constriction
60
What does sympathetic innervation of the pupil result in?
Dilatation
61
What can lead to a constricted pupil?
Loss of parasympathetic input
62
What can lead to a fixed, dilated pupil?
Damage anywhere within the sympathetic pathway can lead to a constricted pupil
63
What are some causes of dilated pupils?
- Youth
- Dim lighting
- Anxiety, excitement
- “Mydriatic” eye drops
- Amphetamine, cocaine overdose
- Third nerve palsy
- Brain death
64
What are some causes of constricted pupils?
- Old age
- Bright light
- “Miotic” eye drops
- Opiate overdose
- Horner’s Syndrome
65
Give examples of eye movement disorders.
- Isolated third nerve palsy
- Isolated fourth nerve palsy
- Isolated sixth nerve palsy
- Combination of the above
- Supranuclear gaze palsy
- Nystagmus
66
What are some microvascular causes of isolated third nerve palsy?
- Diabetes
| - Hypertension
67
How does a third nerve palsy present if it is microvascular in origin?
Painless, pupil spared
68
How does a third nerve palsy present if it is compressive in origin?
Painful, pupil affected
69
What are some compressive causes of isolated third nerve palsy?
- Posterior communicating artery aneurysm
| - Raised ICP
70
What can cause isolated sixth nerve palsy?
- Idiopathic
- Diabetes
- Meningitis
- Raised intracranial pressure
71
What can cause nystagmus?
- Congenital
- Serious visual impairment
- Peripheral vestibular problem
- Central vestibular / brainstem disease
- Cerebellar disease
- Toxins (medication and alcohol)
72
What is trigeminal neuralgia?
Paroxysmal attacks of lancinating pain that has triggers
73
What causes trigeminal neuralgia?
Vasuclar loop (compression of fifth nerve in the posterior fossa)
74
How is trigeminal neuralgia treated?
- Treated medically with carbamazepine
| - Surgical options if medication resistant
75
Who does trigeminal neuralgia affect?
Middle age and older
76
What is Bell's palsy?
Idiopathic facial nerve palsy
| -Unilateral facial weakness
77
What is Bell's palsy often preceded by?
Pain behind the ear
78
How is Bell's palsy treated?
Treated with steroids and usually good recovery
79
Why is there risk of corneal damage in Bell's palsy?
Eye closure is affected
80
Give 2 UMN causes of facial paralysis.
- Stroke
| - Tumour
81
Give 3 LMN causes of facial paralysis.
- Bell's palsy
- Lyme
- Sarcoid
82
How does vestibular neuronitis present?
- Sudden onset
- Disabling vertigo
- Vomiting
- Gradual recovery
83
What is the cause of vestibular neuronitis?
Cause uncertain but possibly viral
84
Dysarthria
-Disordered articulation, slurring of speech
85
Dysphagia
Difficulty swallowing
86
What is the pathology of pseudobulbar palsy?
Bilateral UMN lesions
87
What is the pathology of bulbar palsy?
Bilateral LMN lesions affecting IX - XII
88
What can occur in both bulbar and pseudobulbar palsy?
Dysarthria and dysphagia
89
How does pseudobular palsy present?
- Dysarthria
- Dysphonia
- Dysphagia
- Spastic, immobile tongue
- Brisk jaw jerk
- Brisk gag reflex
90
Give an example of a cause of pseudobulbar palsy.
Bilateral UMN lesions e.g. in vascular lesions of both internal capsules, MND
91
Give examples of causes of bulbar palsy
- MND
- Polio
- Tumours
- Vascular lesions of the medulla
- Syphilis
92
How does bulbar palsy present?
- Wasted, fasciculating tongue
- Dysarthria
- Dysphonia
- Dysphagia
93
What should you beware of doing in bulbar palsy patients?
Feeding patients
