Cranial nerves Flashcards
1
Q
How many cranial nerves are there?
A
12 pairs
2
Q
What do parasympathetic nerves innervate?
A
Glands, smooth muscle
3
Q
Is there any sympathetic outflow from the skull?
A
No
4
Q
What nerve fibres are present in olfactory nerve?
A
Special sensory
5
Q
What nerve fibres are present in optic nerve?
A
Special sensory
6
Q
What nerve fibres are present in oculomotor nerve?
A
Motor
Parasympathetic
7
Q
What nerve fibres are present in trochlear nerve?
A
Motor
8
Q
What nerve fibres are present in trigeminal nerve?
A
Motor
Sensory
9
Q
What nerve fibres are present in abducens nerve?
A
Motor
10
Q
What nerve fibres are present in facial nerve?
A
Motor
Sensory
Parasympathic
11
Q
What nerve fibres are present in vestibulocochlear nerve?
A
Special sensory
12
Q
What nerve fibres are present in glossopharyngeal nerve?
A
Sensory
Motor
Parasympathetic
13
Q
What nerve fibres are present in vagus nerve?
A
Sensory
Motor
Parasympathetic
14
Q
What nerve fibres are present in spinal accessory nerve?
A
Motor
15
Q
What nerve fibres are present in hypoglossal nerve?
A
Motor
16
Q
Where does the olfactory nerve fibres pass through the skull?
A
Cribiform plate of ethmoid
17
Q
What is the name for lost sense of smell?
A
Anosmia
18
Q
An increase in ICP can result in which eye condition?
A
Papillodema
19
Q
A lesion at the optic chiasm will result in what type of visual field loss?
A
Bitemporal hemianopsia
20
Q
A lesion at the right optic tract will result in what type of visual field loss?
A
left homonymous hemianopsia
21
Q
Which foramen does the optic nerve pass through?
A
Optic foramen
22
Q
Where do the retinal nerve fibres synapse?
A
Lateral geniculate body
23
Q
Where does the oculomotor nerve originate?
A
Midbrain
24
Q
Where does the oculomotor emerge from the skull?
A
Superior orbital fissure
25
What does the oculomotor supply in the eye?
```
Extraocular muscles & eyelid
Constricts pupil (circular muscles) & accommodates lens (ciliary muscle)
```
26
If the oculomotor is lesioned, what will be observed?
Ptosis (eyelid drooping)
Eyeball abducted and pointing down
No pupillary reflex
No accommodation
27
Where does the trochlear nerve exit the skull?
Superior orbital fissure
28
What does the trochlear nerve supply?
Superior oblique (turns eye down)
29
What happens is the trochlear nerve is lesioned?
Diplopia (On looking down)
30
Where does the abducent nerve originate?
Pons
31
Where does the abducent nerve exit the skull?
Superior oblique fissure
32
What does the abducent nerve supply?
Lateral rectus muscle
33
If the abducens nerve is lesioned what happens?
Medial deviation of eye causing diplopia
34
Where does the trigeminal emerge from?
Pons
35
Where does the trigeminal (ophthalmic) nerve exit the skull?
Superior orbital fissure
36
What does V1 supply?
Sensory to cornea, forehead, scalp, eyelids & mucosa of nasal sinuses
37
Where does the V2 division of the trigeminal nerve exit the skull?
Foramen rotundum
38
What does the V2 nerve supply?
Sense to the face of maxilla, teeth, TMJ joint & mucosa of maxillary sinuses
39
Where does the V3 branch of trigeminal nerve exit the skull?
Foramen ovale
40
What does the V3 branch of the trigeminal supply?
Sense to mandible, mucosa of mouth & anterior 2/3rds of tongue
Muscles of mastication
41
If the trigeminal nerve is lesioned what are the clinical signs?
Paralysis of muscles of mastication
loss of corneal reflex
loss of face sensation
trigeminal neuralgia
42
Where does the facial nerve originate?
Pontomedullary junction
43
Where does the facial nerve travel?
Internal acoustic meatus and out via the stylomastoid foramen
44
What does the facial nerve supply?
Muscles of facial expression
Innervation of submandibular & submental salivary glands
taste to anterior 2/3rd of tongue
General sensory - external acoustic meatus
45
If the facial nerve is lesioned what clinical signs can be observed?
Bell's palsy (cannot close eyelid, drooping of mouth)
46
What nerve is the most frequently injured?
Facial nerve
47
Where does the vestibulocochlear nerve originate?
Pontomedullary junction
48
Where does the vestibulocochlear nerve exit the skull?
Internal acoustic meatus
49
What are the clinical signs observed with a lesion of nerve VIII?
Tinnitus
Deafness
Vertigo
Nystagmus (involuntary rapid eye movements )
50
Where does the glossopharyngeal nerve originate?
Medulla
51
Where does the glossopharyngeal nerve exit the skull?
Jugular foramen
52
What does the glossopharnygeal nerve supply?
Taste posterior 1/3rd of tongue
sensation for middle ear & posterior oral cavity
innervation of parotid gland
stylopharyngeus innervation
53
When the glossopharyngeal nerve is lesioned, what are the clinical signs?
Loss of gag reflex & taste from back of tongue
54
Where does the vagus nerve exit the skull?
Jugular foramen
55
What does the vagus nerve supply?
Taste for epiglottis
parasympathetic innervation of pharynx, larynx, trachea, bronchi, heart & gut
Motor control to the pharynx, larynx, palate & oesophagus
56
What are some of the branches of vagus nerve?
Recurrent laryngeal nerve
57
What clinical signs will be observed if the vagus nerve is lesioned?
Difficulty swallowing
| Hoarse voice
58
Where does the spinal accessory nerve exit the skull?
Jugular foramen
59
What does the spinal accessory nerve supply?
Sternocleidomastoid & trapezius
60
If the spinal accessory nerve is lesioned, what clinical signs will be observed?
Weakness in turning head & shrugging shoulder
61
Where does the hypoglossal nerve exit the skull?
Hypoglossal canal
62
What does the hypoglossal nerve supply?
Muscles of tongue
63
What clinical signs will be observed if the hypoglossal nerve is lesioned?
Deviation of tongue to affected side
| Paralysis & muscle atrophy of tongue
64
Which nerves are required for taste?
Facial
Glossopharyngeal
Vagus
65
Which nerves are required for movements of face?
Facial
66
Which nerves are required for chewing?
V3
67
Which nerves are required for swallowing?
Glossopharyngeal
| Accessory
68
Which nerves are required for movements of vocal cords?
Vagus
69
Which nerves have visceral sensory input?
Vagus
| Glossopharyngeal (carotid body & sinus)
70
What are the functions of the cranial nerves?
Special senses
Ordinary sensation
Autonomic
Motor control
71
Which are the nerves of special sense?
I - olfaction
II - vision
XII, IX, X - taste
VIII - hearing
72
What nerves supply sensation to the ear?
VII & IX
73
Which nerve supplies muscles of mastication?
Trigeminal (mandibular branch)
74
Which nerve supplies muscles of facial expression?
Facial
75
Which nerve supplies muscles of pharynx & larynx?
Vagus
76
Which nerves supplies SCM & trapezuis?
Accessory spinal
77
Which nerves carry parasympathetic innervation?
III, VII, IX, X
78
What does parasympathetic activity in III nerve mediate ?
Pupillary constriction
79
What does parasympathetic activity in VII nerve mediate ?
Submandibular & Sublingual salivary gland
80
What does parasympathetic activity in IX nerve mediate ?
Parotid salivary gland
81
What does parasympathetic activity in X nerve mediate ?
Organs of abdomen & thorax
82
What nerves are involved in the pupillary reflex?
II - AFFERENT
| III- Efferent
83
What nerves are involved in the corneal reflex?
V- Afferent
| VII- efferent
84
What nerves are involved in the jaw jerk reflex?
V - afferent & efferent
85
What nerves are involved in the GAG reflex?
IX afferent
| X efferent
86
Which cranial nerve nuclei are found in the midbrain?
III, IV
87
Which cranial nerve nuclei are found in the pons?
V, VI, VII
88
Which cranial nerve nuclei are found in the pontomedullary junction?
VIII
89
Which cranial nerve nuclei are found in the medulla?
IX, X, XI, XII
90
How can cranial nerves be damage?
Ischaemia
Crossing sub-arachnoid space (eg. meningitis)
Outside skull, eg tumours
91
What is the pathology behind optic neuritis? What disease is it associated with?
Demyelination of the optic nerve
MS
92
What are the signs of optic neuritis?
```
Monocular vision loss
Pain on eye movement
Reduced visual acuity
Reduced colour vision
Swelling of optic disc
```
93
What can cause dilated pupils?
```
Dim light
Young
3rd nerve palsy
"Mydriatic" eye drops
Amphetamine & cocaine
Brainstem death (Bilateral)
```
94
What cause pupils to constrict?
```
Old age
Bright light
Miotic eye drops
Opiate overdose
Horner's syndrome (sympathetic plexus)
```
95
What are the microvascular causes of 3rd nerve palsy?
| What are the symptoms?
Diabetes & hypertension
Painless & pupil spared
96
What are the compressive causes of 3rd nerve palsy?
| What are the symptoms?
Posterior communicating artery aneurysm
Raised ICP
Painful & pupil affected
97
What are the causes of 6th nerve palsy?
Meningitis
Raised ICP
Diabetes
98
Trigeminal neuralgia presents as painful attacks due to the compression of which nerve?
V
99
What is Bell's Palsy?
Idiopathic facial (VII) nerve palsy
100
What is observed with Bell/s palsy?
Unilateral facial weakness
| Inability to close eye
101
What are some of the LMN causes of facial nerve palsy?
Bell's palsy
| Lymes diseae
102
What are some of the UMN causes of facial nerve palsy?
Stroke
| Tumour
103
What will be the signs of UMN facial palsy?
The forehead will be spared
104
What will be the signs of LMN facial palsy?
The whole side of the face will be affected including forehead
105
What are the symptoms of vestibular neuronitis?
Sudden onset of vertigo
Vomiting
Gradual recovery
106
What is dysarthria?
Slurred speech
| Disordered articulation
107
What is dysphonia?
Loss of volume of speech
108
What is dysphagia?
Difficulty swallowing
109
What is the difference between bulbar palsy & pseudo bulbar palsy?
```
Pseudobulbar = UMN
Bulbar = LMN
```
110
What is the pathology of Pseudobulbar palsy?
Bilateral vascular lesion of the internal capsule
111
What are some of the symptoms/ signs of pseudo bulbar palsy?
```
Dysarthria
Dysphonia
Dysphagia
Spastic immobile tongue
Brisk jaw & gag reflex
```
112
What nerves does bulbar palsy affect?
IX-XII
113
Where is the lesion in bulbar palsy?
Bilateral lesion of LMN in brainstem
114
What are some of the symptoms/ signs of bulbar palsy?
Dysarthria
Dysphonia
Dysphagia
Wasted, fasciulcating tongue
