Disorders of Cranial Nerves

Question 1

Which cranial nerves are special sensory?

Answer 1

I - olfaction
II - vision
VII, IX, and X - taste
VIII - hearing

Question 2

Which cranial nerves are ordinary sensory?

Answer 2

CN V
CN VII
CN IX

Question 3

Which CN control eye muscles?

Answer 3

III
IV - SO
VI - LR

Question 4

Which CN controls muscles of mastication?

Answer 4

CN V3

Question 5

Which CN controls muscles of facial expression?

Answer 5

CN VII (facial)

Question 6

Which CN controls muscles of the larynx and pharynx?

Answer 6

Mainly CNX (vagus)

Question 7

Which CN controls the sternocleidomastoid and trapezius muscles/

Answer 7

CN XI (accessory)

Question 8

Which CN controls lacrimation?

Answer 8

CN VII

Question 9

Which CN controls salvation from submandibular and sublingual glands?

Answer 9

CN VII

Question 10

Which CN controls salivation from parotid glands?

Answer 10

CN IX

Question 11

Which CN controls pupillary constriction?

Answer 11

CN III

Question 12

How do we test CN I?

Answer 12

Change in smell

Uni or bi lateral

Question 13

How do we test CN II?

Answer 13

Visual fields 
Visual acuity 
Pupillary response 
Colour vision 
Fundoscopy

Question 14

How do we test CN III, IV and VI?

Answer 14

Eye movements
Horizontal and vertical H shape
Equal size pupils

Question 15

What tests are carried out for CN V function?

Answer 15

Sensation in V1,2,and 3 area
Neurotip and cotton wool 
Corneal reflex (sensory part)
Power of muscles of mastication 
Jaw jerk reflex

Question 16

How do we test CN VII?

Answer 16

Make facial expressions
Corneal reflex (motor control)
Taste (sometimes)

Question 17

HOw do we test CN VIII?

Answer 17

Hearing

Rinne’s and Weber;s

Question 18

What tuning fork is used in hearing tests?

Answer 18

512 Hz

Question 19

How is CN IX and CN X tested?

Answer 19

Movement of the palate (symmetrical)
Gag reflex
Quality of speech
Quality of cough

Question 20

How is CN XI tested?

Answer 20

Move shoulders up and down to test the trapzius muscle

Head turning to test the sternocleidomastoid

Question 21

How is CN XII tested?

Answer 21

Movement of tongue

Test speech

Question 22

Which is the afferent CN of pupillary reflex?

Answer 22

CN II

Question 23

What is the efferent CN of pupillary reflex?

Answer 23

CN III

Question 24

What is the afferent CN of corneal reflex?

Answer 24

CN V

Question 25

What is the efferent CN of corneal reflex?

Answer 25

CN VII

Question 26

What is the afferent and efferent CN of jaw reflex?

Answer 26

CN V for both

Question 27

What is the afferent CN for gag reflex?

Answer 27

CN IX

Question 28

What is the efferent CN for gag reflex?

Answer 28

CN X

Question 29

Where are CN III and IV nuclei located in the brain?

Answer 29

Mid brain

Question 30

Where are CN V, VI and VII nuclei located?

Answer 30

In the pons

Question 31

Where is CN VIII nuclei located?

Answer 31

In the pontomedullary junction

Question 32

Where is CN IX, X, XI and XII nuclei located?

Answer 32

In the medulla

Question 33

What is the differential diagnosis for loss of eye movements, facial weakness and difficulty swallowing?

Answer 33

Stroke | Cranial nerve disorders

Question 34

What causes optic neuritis?

Answer 34

Demyelination within the optic nerve

Question 35

What is optic neuritis often associated with?

Answer 35

MS

Question 36

What are the symptoms of optic neuritis?

Answer 36

``` Monocular visual loss Pain on eye movement Reduced visual acuity Reduced colour vision Optic disc may be swollen ```

Question 37

Palsy of which CN would result in a fixed dilated pupil?

Answer 37

CN III

Question 38

What can lead to a constricted pupil?

Answer 38

Damage anywhere within the sympathetic pathway

Question 39

What are causes of dilated pupils?

Answer 39

``` Youth Dim lighting Anxiety, excitement Drugs 3rd nerve palsy Brain death ```

Question 40

What are causes of constricted pupils?

Answer 40

``` Odl age Bright light Miotic eye drops Opiate overdose Horners syndrome Damage to the sympathetic chain ```

Question 41

What can cause eye movement disorders?

Answer 41

Isolated CN III, IV or VI palsy Combination of the above Supranucleur gaze palsy Nystagmus

Question 42

What are causes of isolated CN III palsy?

Answer 42

Microvascular (diabetes, hypertension) | Compressive ( due to artery aneurysm, raised ICP)

Question 43

What are causes of isolated CN VI palsy?

Answer 43

Idiopathic Diabetes Meningitis Raised ICP

Question 44

What are some causes of nystagmus?

Answer 44

``` Congenital Serious visual impairment Vestibular problems Brainstem disease Cerebellar disease Toxins ```

Question 45

What is trigeminal neuralgia?

Answer 45

Paroxysmal attacks of lacinating pain

Question 46

What causes trigeminal neuralgia?

Answer 46

Compression of 5th nerve root in posterior fossa (caused by vascular loops)

Question 47

What is the first line treatment for CN V neuralgia?

Answer 47

Carbamazepine

Question 48

What is the treatment for CN V if medication is resistant?

Answer 48

Surgery

Question 49

What are the signs of bells palsy?

Answer 49

Unilateral facial weakness

Question 50

Is bells palsy UMN of LMN lesion?

Answer 50

LMN

Question 51

What type of pain often precedes bells palsy?

Answer 51

Pain behind the ear

Question 52

Why is there a risk of corneal damage in bells palsy?

Answer 52

Due to failure to close the eyelid

Question 53

How is bells palsy treated?

Answer 53

Usually with steroids

Question 54

What is dysarthria?

Answer 54

Disordered articulation | Slurring of speech

Question 55

What is dysphagia?

Answer 55

Difficulty swallowing

Question 56

Is bulbar palsy UMN or LMN?

Answer 56

LMN

Question 57

Is pseudobulbar palsy UMN or LMN?

Answer 57

UMN

Question 58

What are the signs of bulbar palsy?

Answer 58

``` Wasted, fasiculating tongue Dysarthria Dysphonia Dysphagia Norma gag reflex Nasal speech ```

Question 59

Which CN is affected in bulbar palsy/

Answer 59

CN IX - CN XII