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Flashcards in Cranial nerves Deck (76)
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1
Q

Which three structures make up the brain stem?

A

Midbrain, pons and medulla

2
Q

Which part of the brain are the first and second cranial nerves extensions of?

A

Forebrain - there is no sheath surrounding them but CSF instead

3
Q

Where do nerves 3-7 originate from?

A

Brainstem

4
Q

Which nerves are purely sensory?

A

1,2,8

5
Q

Which nerves are purely motor?

A

3,4,6,11,12

6
Q

Which nervous system controls the cranial nerves?

A

Autonomic

7
Q

What does the olfactory nerve do?

A

Smell

8
Q

Where does the olfactory nerve emerge?

A

Cribriform plate

9
Q

How to test the olfactory plate

A

Change in sense of smell

10
Q

Injury to olfactory nerve

A

Unilateral/bilateral anosmia

11
Q

Function of optic nerve

A

Vision and pupil reflex

12
Q

Where does optic nerve emerge?

A

Optic canal

13
Q

How to test optic nerve

A

Snellen chart

14
Q

Injury to optic nerve

A

Ipsilateral blindness

Pituitary tumour = tunnel vision

15
Q

Function of oculomotor nerve

A

MR, IR, SR, IO

Upper eyelid

16
Q

Where does the oculomotor nerve exit?

A

Superior orbital fissure

17
Q

How to test oculomotor nerve

A

‘H’ movement

18
Q

Injury to oculomotor nerve

A

Ptosis, double vision, divergent quint, dilated pupils

19
Q

Function of trochlear nerve

A

Superior oblique muscle

20
Q

Where does trochlear nerve exit?

A

Superior orbital fissure

21
Q

How to test trochlear nerve

A

Follow finger - bring the eye to the nose and back down

22
Q

Injury to trochlear nerve

A

Nystagmus (involuntary eye movement)
Diplopia
Vision converging

23
Q

What are the three branches of the trigeminal nerve?

A

Ophthalmic
Maxillary
Mandibular

24
Q

Function of ophthalmic branch of trigeminal nerve

A

Sensory function of scalp forehead and nose

25
Q

Where does the ophthalmic branch of trigeminal nerve exit the skull?

A

Superior orbital fissure

26
Q

How to test trigeminal nerve

A

Corneal light reflex with VII
Assess light touch/pin prick for sensory
Corneal reflex tested using wisp of wool
Clench jaw and open against my hand

27
Q

Injury of trigeminal nerve

A

Ipsilateral anesthesia
Paralysis of ipsilateral muscles of mastication
Carcinoma tongue (lingual nerve) cause severe earache

28
Q

Function of maxillary branch of trigeminal nerve

A

Sensory: Cheeks, lower eyelid, nasal mucosa, upper lip, upper teeth, palate

29
Q

Where does the maxillary branch of trigeminal nerve exit the skull?

A

Foramen rotundum

30
Q

Function of mandibular branch of trigeminal nerve?

A

Sensory: anterior 2/3 tongue, skin over mandible and lower teeth
Motor: mastication

31
Q

Where does the mandibular branch of the trigeminal nerve exit the skull?

A

Foramen vale

32
Q

What are the three divisions of the ophthalmic branch of the trigeminal nerve?

A

Frontal (supraorbital and supratrochlear), lacrimal and nasociliary (eyeball, cornea and conjunctiva)

33
Q

What nerve can be damaged when the anterior cranial fossa is damaged?

A

Olfactory

34
Q

Symptoms of temporal lobe epilepsy

A

Olfactory hallucinations

35
Q

Symptoms of frontal lobe tumour

A

Unilateral anosmia

36
Q

Can the optic nerve regenerate after division?

A

No

37
Q

What happens in the optic chiasma?

A

Nerves from each eye are shared

38
Q

Symptoms of retinal/optic lesions

A

Ipsilateral blindness

39
Q

What does AFRO stand for?

A

Acuity
Fields
Reflexes
Opthalmoscopy

40
Q

What is the MR?

A

Medial rectus

41
Q

What is the IR?

A

Inferior rectus

42
Q

What is the SO?

A

Superior oblique

43
Q

What is the IO?

A

Inferior oblique

44
Q

Path of oculomotor nerve

A

Brain - cavernous sinus - extrinsic ocular muscles

45
Q

What is ptosis?

A

Drooping of upper eyelid

46
Q

Function of abducens

A

Motor of lateral rectus

47
Q

Where does abducens exit skull?

A

Superior orbital fissure

48
Q

How to test abducens

A

Follow penlight with eye to all 4 quadrants

49
Q

Injury to abducens

A

Nystagmus, diplopia, convergence of vision

50
Q

Functions of facial nerve

A

Sensory: taste to anterior 2/3 of tongue
Motor: facial muscles, crying (lachrymal gland), salivating (sublingual and submandibular) and tasting (chorda tympani)

51
Q

Where does facial nerve exit skull?

A

Internal acoustic meatus

52
Q

How to test facial nerve

A
Raising eyebrows – temporal
Scrunching eyes – zygomatic
Blow cheeks – buccal
Show teeth – mandibular
Resist these motions and assess power
53
Q

Injury to facial nerve

A

Ramsay-Hunt syndrome: herpes zoster oticus – shingles affects facial nerve involving geniculate ganglion
Shingles rash, facial paralysis, hearing loss
Altered taste perception, saliva and tear production

54
Q

Function of vestibulocochlear nerve

A

Hearing and balance

55
Q

Where does the vestibulocochlear nerve exit the skull?

A

Internal acoustic meatus

56
Q

How to test vestibulocochlear nerve

A

Obscure pt’s ear canal and eyes

Whisper letter and number and ask pt to repeat

57
Q

Injury to vestibulocochlear nerve

A

Hearing loss, vertigo, false sense of motion

58
Q

Function of glossopharyngeal nerve

A

Sensory: posterior third of tongue, pharynx, middle ear
Motor: stylopharyngeus (palate)
Autonomic: salivary glands

59
Q

Where does glossopharyngeal nerve exit skull?

A

Jugular foramen

60
Q

How to test glossopharyngeal nerve

A

Sensory part of gag reflex with vagus
Ask to cough and swallow water
Say ahhhhh – look for

61
Q

Injury to glossopharyngeal nerve

A

Sensory loss of pharynx
Loss of taste and sensation to posterior 1/3 of tongue
Pharangeal weakness, loss of saliva
Rarely isolated – usually involves X

62
Q

Function of vagus nerve

A

Sensory: tympanic membrane, external auditory canal, ear
Motor: palate, pharynx, larynx
Autonomic: afferents from carotid baroreceptors

63
Q

Where does vagus nerve exit skull?

A

Jugular foramen

64
Q

How to test vagus nerve

A

Pt’s voice quality
Ask them to say ahhhhh – note elevation of soft palate and uvula
Gag reflex

65
Q

Injury to vagus nerve

A

Stridor – noisy breathing
Aspiration – inhale into airway
Dys/aphonia – difficulty speaking
If recurrent laryngeal nerve damaged after surgery, cricothyroid muscle still works and can tense muscles in larynx

66
Q

Function of spinal accessory nerve

A

Motor: sternocleideomastoid and trapezius, shrug shoulders

67
Q

Where does spinal accessory nerve exit skull?

A

Jugular foramen

68
Q

How to test spinal accessory nerve

A

Ask pt to shrug shoulders and turn face against your hands

69
Q

Injury of spinal accessory nerve

A

Weakness of trapezius - winged scapula

70
Q

Function of hypoglossal nerve

A

Intrinsic and extrinsic tongue muscles except palatoglossus

71
Q

Where does hypoglossal nerve exit skull?

A

Hypoglossal canal

72
Q

How to test hypoglossal nerve

A

Stick out tongue, note fasciculation, deviation and abnormality in muscle
Push against mouth to test resistance

73
Q

Injury to hypoglossal nerve

A

Atrophy of tongue on affected side
Ipsilateral paralysis, wasting and deviation when pushed to affected side
UMN lesion in corticobulbar palsy = bilateral paralysis with no wasting

74
Q

What are the 5 branches of the facial nerve?

A
Temporal
Zygomatic
Buccal
Mandibular
Cervical
75
Q

Function of utricle

A

Horizontal movement

76
Q

Function of saccule

A

Linear acceleration and gravity