Disorders of cranial nerves

Question 1

What cranial nerves are responsible for taste?

Answer 1

7,9,10

Question 2

What cranial nerves allow general sensation in the ear?

Answer 2

7 and 9

Question 3

Afferent and efferent cranial nerves of pupillary light reflex

Answer 3

afferent = 2 
efferent = 3

Question 4

Afferent and efferent cranial nerves for corneal reflexes

Answer 4

afferent = 5 
efferent = 7

Question 5

Afferent and efferent cranial nerves for jaw jerk reflex

Answer 5

both 5

Question 6

Afferent and efferent cranial nerves for gag reflex

Answer 6

afferent = 9
efferent = 10

Question 7

Briefly state the location of the origin of the cranial nerves

Answer 7

3,4 - midbrain
5,6,7 - pons
8 - pontomedullary junction
9-12 - medulla

Question 8

Causes of unusual cranial nerve signs?

Answer 8

chronic or malignant meningitis

Question 9

Causes of pure motor cranial nerve signs?

Answer 9

myasthenia gravis

Question 10

Give 2 examples of cranial nerve signs with no cranial nerve lesion

Answer 10

after stroke

myasthenia gravis, thyroid eye disease - double vision

Question 11

Causes of cranial nerve damage in the brain

Answer 11

tumour, ischaemia

Question 12

Causes of cranial nerve damage crossing subarachnoid space

Answer 12

meningitis

Question 13

Causes of cranial nerve damage outside skull

Answer 13

base of skull tumours arising from nasopharynx

Question 14

Symptoms of optic neuritis

Answer 14

pain on eye movement

reduced visual acuity and colour vision

Question 15

What is optic neuritis?

Answer 15

demyelination within the optic nerve

Question 16

What is the sign of optic neuritis and what is it associated with?

Answer 16

swollen optic disc

MS

Question 17

Loss of parasympathetic innervation leads to what appearance of the pupil?

Answer 17

fixed, dilated

Question 18

Loss of sympathetic innervation leads to what appearance of the pupil?

Answer 18

constricted

Question 19

List some causes of dilated pupils

Answer 19

youth, anxiety, cocaine, brain death, mydriatic eye drops, dim lighting

Question 20

List some causes of small pupils

Answer 20

bright light, middle age, miotic eye drops, opiate overdose, horners syndrome

Question 21

Difference between microvascular and compressive 3rd nerve palsy

Answer 21

microvascular is painless and pupil is spared

Question 22

Causes of microvascular and compressive 3rd nerve palsy

Answer 22

diabetes, hypertension

posterior communicating aneurysm, raised ICP

Question 23

Causes of isolated 6th nerve palsy

Answer 23

idiopathic, diabetes, meningitis, raised ICP

Question 24

Causes of nystagmus

Answer 24

congenital, toxins, serious visual impairment, cerebellar disease, peripheral vestibular problem, central vestibular/brainstem disease

Question 25

What Is trigeminal neuralgia?

Answer 25

paroxysmal attacks of lacinating pain usually in middle age and older

Question 26

Cause of trigeminal neuralgia?

Answer 26

vascular loop - compression 5th cranial nerve in posterior fossa

Question 27

How is trigeminal neuralgia treated?

Answer 27

carbamazepine or surgery

Question 28

What usually precedes bells palsy?

Answer 28

pain behind ear

Question 29

bells palsy symptoms and signs

Answer 29

unilateral facial weakness eye closure affected risk of corneal damage

Question 30

Is bells palsy LMN or UMN?

Answer 30

LMN

Question 31

How is bells palsy treated?

Answer 31

steroids

Question 32

Give an example of UMN and LMN facial nerve palsy

Answer 32

UMN eg stroke, tumour | LMN eg bells palsy

Question 33

Describe vestibular neuronitis

Answer 33

sudden onset disabling vertigo and vomiting | thought to be viral cause, gradual recovery

Question 34

dysarthria

Answer 34

disordered articulation and slurring of speech

Question 35

What is bulbar and pseudobulbar palsy?

Answer 35

``` bulbar = LMN pseudobulbar = UMN ```

Question 36

Causes of pseudobulbar palsy

Answer 36

MND, vascular lesions of both internal capsules

Question 37

Symptoms of pseudobulbar palsy

Answer 37

``` dysarthria dysphonia dysphagia spastic, immobile tongue brisk gag and jaw jerk reflex ```

Question 38

What cranial nerves does bulbar palsy encompass?

Answer 38

9-12

Question 39

Causes of bulbar palsy

Answer 39

MND, polio, tumour

Question 40

Symptoms of bulbar palsy

Answer 40

wasted, fasciculating tongue dysarthria dysphonia dysphagia

Question 41

What do you need to beware of with bulbar palsy patients?

Answer 41

feeding