Cranial Nerves - Lecture 8\ Flashcards

1
Q

how many cranial nerves arise emerge from the brain

A

12 pairs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what do the cranial nerves pass through

A

skull foramina

fissures

canals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what do cranial nerves distribute

A

their innervation to different structures in the head and neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

which nerves is the “wanderer”

A

vagus nerve

continuous into the trunk and supplies the thoracic region and abdominal organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how are cranial nerves numbered

A

in the order they arise in the brain

rostrally to caudally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

cranial nerves can be

A

sensory

motor

mixed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

CN1

A

olfactory nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

where does CN1 arise from

A

olfactory epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

where does CN1 run through

A

cribriform plate of the ethmoid bone

through the olfactory bulb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

where does CN1 terminate

A

primary olfactory cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

CN1 fxn

A

carrying afferent impulses for the sense of smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is CN1

A

special visceral afferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

parts of CN1

A

olfactory bulb

olfactory tract

temporal cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

with age CN1

A

olfactory ability decreases with age

anosmia: impaired

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

CN2

A

optic nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

where does CN2 arise from

A

retina of the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what does CN2 pass through

A

optic canals and converge at the optic chiasm

continue to the thalamus where they synapse

then run to visual cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

CN2 fxn

A

carrying afferent impulses for vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is CN2

A

special somatic afferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how does vision run

A

retina –> optic nerve –> optic chiasm –> lateral geniculate body –> optic radiations –> visual cortex in occipital lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

clinically injury to CN2 results in

A

visual field loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

CN3

A

oculomotor N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how do fibers of CN3 run

A

fibers extend from the ventral midbrain

pass through the superior orbital fissure

go to the extrinsic eye muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

CN3 fxn

A

raising the eyelid

directing the eyeball

constricting the iris

controlling lens shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

CN3 ptosis

A

eyelid droop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

CN3 ophthalmoplegia

A

problems in adjusting to light

deviation of eye movements

diplopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is diplopia

A

double vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

CN4

A

trochlear N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

where do fibers of CN4 emerge from

A

dorsal midbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

where do CN4 fibers enter

A

orbits via the superior orbital fissures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what does CN4 innervate

A

superior oblique muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

CN4 is a

A

motor nerve

directs the eyeball

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is CN4

A

general somatic efferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is CN4 the only to do

A

exit brainstem dorsally

exits contralaterally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Fxn of CN4

A

anterior oblique muscle for eye movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

clinically CN4

A

difficulty looing downward and outward when trochlear is injured

eye drifts upward relative to the normal eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

CN5

A

trigeminal N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

3 divisions of CN5

A

opthalamic (V1)

maxillary (V2)

mandibular (V3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what does Cn5 convey

A

sensory impulses from various areas of the face

V1 and V2

supplies motor fibers for mastication (V3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what is CN5

A

general somatic afferent

special visceral efferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what is CN5 principle for

A

principle sensory nerve for head, face, orbit and oral cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what does CN5 mediate

A

sensations of pain, temperature, proprioception and fine discriminative touch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

3 sensory branches of CN5

A

opthalamic

maxillary

mandibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

CN5 is motor for

A

mastication muscles for chewing and speaking

reflex for jaw jerk reflex (mandibular)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

muscles for chewing and speaking

A

internal and external pterygoid

temporalis

masseter

mylohyoid

anterior belly of digastric

tensor veli palatini

tensor tympani

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

CN5 tic doulourex or trigeminal neuralgia

A

most excruciating pain known

caused by inflammation of nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

severe cases of tic doulourex or trigeminal neuralgia

A

nerve is cut

relieves agony but results in loss of sensation on that side of the face

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

CN6

A

abducens N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

where do CN6 fibers leave

A

inferior pons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

where do CN6 fibers enter

A

orbit

via the superior orbital fissure

51
Q

what does CN6 innervate

A

lateral rectus muscle

abducts the eye

motor nerve

52
Q

what is CN6

A

general somatic efferent

53
Q

CN6 injured

A

medial rectus muscle is unopposed –> eye shifts medially

54
Q

CN6 is susceptible to

A

disruption

55
Q

CN6 –> medial strabismus

A

turns in medially

double vision

56
Q

CN7

A

facial nerve

57
Q

what is CN7

A

general visceral efferent

special visceral afferent

special visceral efferent

58
Q

PS innervation CN7

A

lacrimal gland and palatal saliva

59
Q

what does CN 7 innervate

A

mucous membrane secretions in mouth and pharynx

60
Q

CN7 –> special visceral afferent

A

gustatory sensations from anterior 2/3 of tongue

61
Q

CN 7 -> special visceral efferent

A

primary motor nerve for facial muscles

lacrimal secretion –> tears

62
Q

Bell’s Palsy –> Cn7

A

paralysis of facial muscles on affected side and loss of taste sensation

63
Q

what causes bells palsy

A

herpes simplex I virus

64
Q

what happens to someone with bell’s palsy

A

lower eyelid droops

corner of mouth sags

tears drip continuously

eye cannot be complete closed (dry eye may occur)

65
Q

bells palsy may

A

disappear spontaneously without treatment

66
Q

CN8

A

vestibulocochlear

67
Q

CN8 fibers arise from

A

hearing and equilibrium apparatus of the inner ear

68
Q

what do CN8 fibers pass through

A

internal acoustic meatus

69
Q

where do CN8 fibers enter

A

brainstem at the pons-medulla border

70
Q

2 divisions of CN8

A

cochlear (hearing)

vestibular (balance)

71
Q

fxn CN8

A

sensory

equilibrium and hearing

72
Q

what is CN8

A

special somatic afferent

73
Q

vestibular nerve –> CN8

A

gives feedback about position of head in space and balance

74
Q

acoustic N –> CN8

A

hearing

75
Q

CN8 clinically

A

tests for equilibrium, vertigo, or dizziness, nystagmus and hearing loss

76
Q

CN9

A

glossopharyngeal N

77
Q

CN9 fibers emerge from

A

medulla

78
Q

how do CN9 fibers leave the skull

A

jugular foramen

run to throat

79
Q

CN9 is

A

mixed nerve with motor and sensory fxns

80
Q

CN9 –> motor

A

innervates part of the tongue and pharynx

provides motor fibers to the parotid salivary gland

81
Q

CN9 –> sensory

A

fibers conduct taste and general sensory impulses from the tongue and pharynx

82
Q

what is CN9

A

general visceral afferent

general visceral efferent

special visceral afferent

special visceral efferent

83
Q

CN9 general visceral afferent

A

mediates general visceral sensation from soft palate, palatal arch, posterior 1/3 of tongue and carotid sinus

84
Q

CN9 general visceral efferent

A

secretion from parotid gland

salivary gland

85
Q

CN9 special visceral afferent

A

taste sensation from posterior 1/3 of tongue

86
Q

CN9 special visceral efferent

A

contributes to swallowing through stylopharyngeus and upper pharyngeal constrictor fibers

87
Q

CN9 clinically

A

may be evident in dysphagia or loss of taste to posterior 1/3 of tongue

loss of gag reflex

excessive oral secretions

dry mouth

88
Q

what does CN9 need to have strong clinical signs

A

bilateral damage

89
Q

CN 10

A

vagus N

90
Q

where do CN10 fibers emerge

A

medulla via jugular foramen

91
Q

CN10 is a

A

mixed nerve

92
Q

most fibers of Cn10 are

A

PS fibers to the heart, lungs and visceral organs

93
Q

CN10 sensory fxn

A

taste

94
Q

what does paralysis of CN10 lead to

A

hoarseness

95
Q

total destruction of CN10

A

incompatible with life

96
Q

general visceral afferent –> CN10

A

sensation from pharynx, larynx, thorax, abdomen

regulates nausea, oxygen intake, lung inflation

97
Q

general visceral efferent –> CN10

A

innervates glands, cardiac muscles, trachea, bronchi, esophagus, stomach and intestine

98
Q

special visceral afferent –> Cn10

A

mediates taste sensation from posterior pharynx and epiglottis

99
Q

special visceral efferent –> CN10

A

controls muscles of larynx, pharynx, soft palate for phonation, swallowing and resonance

100
Q

bilateral lesion to brainstem –> Cn10

A

fatal d/t respiratory involvement

101
Q

unilateral lesion to brainstem –> CN10

A

ipsilateral paresis or paralysis of soft palate, pharynx and larynx

102
Q

pharyngeal branch –> CN10

A

pharynx and soft palate involvement

uvula pulled to unaffected side

bilateral soft palate droops

103
Q

recurrent laryngeal branch –> CN10

A

unilateral –> paralysis of vocal folds

bilateral –> inspiratory stridor and aphonia

104
Q

damage to CN10

A

autonomic reflexes reduced

anesthesia of pharynx and larynx

loss of taste

105
Q

damage to superior laryngeal branch –> CN10

A

loss of ability to change pitch

106
Q

CN11

A

accessory N

107
Q

how is CN11 formed

A

by cranial root emerging from the medulla

&

spinal root arising from the superior region of the SC

108
Q

CN11 –> spinal root

A

passes upward into the cranium via the foramen magnum

109
Q

how does CN11 leave the cranium

A

via jugular foramen

110
Q

CN11 is primarily a

A

motor N

111
Q

CN11 –>motor N

A

supplies fibers to the larynx, pharynx and soft palate

innervates the traps and SCM –> move the head and neck

112
Q

CN12

A

hypoglossal N

113
Q

CN12 fibers arise from

A

medulla

114
Q

CN12 exit

A

the skull via the hypoglossal canal

115
Q

what does Cn12 innervate

A

both extrinsic and intrinsic muscles of the tongue

contribute to swallowing and speech

116
Q

damage to CN12

A

difficulties in speech and swallowing

inability to protrude tongue

117
Q

what is CN12

A

general somatic efferent

118
Q

CN12 –> general somatic efferent

A

controls tongue movement

controls extrinsic and intrinsic muscles of tongue expect palatoglossal (X)

eating, sucking and chewing reflexes

119
Q

LMN unilateral lesion –> CN12

A

cause wrinkling and flaccidity of tone with atrophy over time

120
Q

unilateral UMN lesion –> Cn12

A

do not have much affect as tongue is bilaterally innervated

121
Q

CN12 damage

A

dysarthria and dysphagia

122
Q

how can you check CN12 damage

A

ask pt to complete oral motor movements

123
Q

CN combos

A

more than one N involved with some structures

ex: eyes muscle control

124
Q

sensory fibers to tongue –> CN combos

A

anterior 2/3 special and general sensation –> facial and trigeminal

posterior 1/3 special and general sensation –> glossopharyngeal