7 - Head & Neck - Cranial Nerves 2 Flashcards Preview

ESA4 > 7 - Head & Neck - Cranial Nerves 2 > Flashcards

Flashcards in 7 - Head & Neck - Cranial Nerves 2 Deck (35):
1

Name the lining of the cavernous sinus:

Dura mater

2

The cavernous sinus lies in which bone?

Sphenoid bone

3

Which artery passes through the cavernous sinus?

Internal Carotid Artery

4

Describe the location of the Optic Chiasm:

Directly ventral to the pituitary gland

5

Describe the route of CN I from the optic disc to the forebrain:

- Enters skull from the retina via the Optic canal
- Optic nerve runs from retina to optic chiasm
- Crossover occurs at optic chiasm
- Via optic tract to the Geniculate nuclei
- From geniculate nuclei to visual cortex

6

What part of the optic pathway may be compressed by a pituitary tumour? How may this present?

Optic chiasm
Loss of acuity +/- vision

7

Name some toxins which can damage the optic nerve:

- Ethambutol
- Amiodarone
- Methanol
- Tobacco exposure

8

How is the optic nerve tested?

1) Acuity via Snellen chart
2) Colour via Ishihara plates
3) Fields
4) Pupillary light reflexes
5) Fundoscopy

9

How is the oculomotor nerve tested?

- Inspect eyelid and pupils
- Eye movements (H)
- Pupillary light reflexes

10

How does an oculomotor lesion present?

- 'down-and-out' eye
- diplopia
- loss of pupil constriction

11

List some common ways the oculomotor nerve is damaged:

- Tumour/haemorrhage = increased intracranial pressure
- Aneurysm
- Cavernous sinus thrombosis
- Diabetes
- Hypertension

12

How is the trochlear nerve tested?

- Eye movements (H)

13

How does a lesion of the trochlear nerve present?

- Very subtle deviation of the eye, may compensate by tilting head
- May have diplopia, worse on downward gaze

14

How is the trigeminal nerve tested?

- Test muscles of mastication by asking to clench jaw
- Corneal reflex (sensation to cornea)
- Sensation to face

15

Which 2 cranial nerves does Shingle most commonly affect?

CN V Trigeminal
CN VII Facial

16

How is the abducens nerve tested?

Eye movements (H)

17

How does a lesion to the abducens nerve present?

Diplopia

18

Where does the facial nerve branch into 5?

Within the Parotid gland

19

How is the facial nerve tested?

Test muscles of facial expression:
- Close eyes against resistance
- Raise eyebrows
- Puff out cheeks
- Reveal teeth

20

What are the common causes of a facial palsy?

- Middle ear tumour
- Infection
- Parotid tumour/infection
- Shingles
- Compression

21

How is the vestibulocochlear nerve tested?

- Hearing
- Rinne's test
- Weber's test

22

Which cranial nerve(s) gives special sensory fibres for taste?

- Anterior 2/3rds of the tongue = Facial nerve
- Posterior 1/3rd = Glossopharyngeal nerve
- Epiglottis and root of tongue = Vagus nerve

23

How is the glossopharyngeal nerve tested?

- Gag reflex

24

Which cranial nerve gives special sensory fibres for taste to the epiglottis and root of tongue?

CN X Vagus

25

How is the vagus nerve tested?

- Check position of uvula
- Speech
- Swallow
- Cough
- Gag reflex

26

Which cranial nerves contain the efferent and afferent limbs of the gag reflex?

Efferent = vagus nerve
Afferent = glossopharyngeal nerve

27

The accessory nerve contains roots from which segments of the c-spine?

C1-5/6

28

How is the accessory nerve tested?

- Shrug shoulders against resistance
- Turn head against resistance

29

If a vagus nerve is damaged, will the uvula deviate towards or away from the side of the lesion?

Away from the side of the lesion

30

Where is the accessory nerve susceptible to injury?

Posterior triangle of neck
- Lymph node biopsy
- Stab wound etc

31

Which cranial nerve crosses the internal and external carotid arteries in the neck?

CN XII Hypoglossal

32

How is the hypoglossal nerve tested?

- Inspection of tongue
- Movement of tongue

33

If a hypoglossal nerve is damaged, will the tongue deviate towards or away from the side of the lesion?

Towards the side of the lesion

34

What is an acoustic neuroma?

A benign tumour around CN VIII

35

If the CN III nerve is damaged, why is the first symptom loss of pupillary constriction?

CN III autonomics 'hitchhike' on the outside of CN III, therefore first to be damaged.