Cranial Nerve Examination

Question 1

What are the signs of Horner’s syndrome?

Answer 1

Ptosis, Miosis, Enophtalmos and facial anhidrosis

Question 2

What are the signs of Third nerve palsy?

Answer 2

The eye is depressed and abducted (down and out)

Elevation, adduction, and depression are limited, but abduction and intortion are normal

There is a ptosis (drooping of the upper eyelid)

The pupil may be dilated and unreactive to light or accommodation

Question 3

What are the signs of Bell’s (facial nerve) palsy?

Answer 3

Facial drooping and paralysis on the affected half

If the forehead muscles are spared, it is central rather than a peripheral palsy

Question 4

What are the signs of Cavernous sinus syndrome?

Answer 4

The cavernous sinus contains the carotid artery and its sympathetic plexus, CN III, IV, and VI, and the ophthalmic and maxillary branches of CN V

Signs of a cavernous sinus lesion may include (generally unilateral) proptosis, chemosis, ophthalmoplegia, and loss of sensation in the first and second divisions of the trigeminal nerve

Question 5

What are the signs of Cerebellopontine angle syndrome?

Answer 5

Lesions in the area of the cerebellopontine angle can cause compression of CN V, VII and VIII

Signs may include palsies of CN V and VII, nystagmus, ipsilateral deafness, and ipsilateral cerebellar signs

Question 6

What are the signs of Bulbar palsy?

Answer 6

Lower motor neurone lesion in the medulla oblongata leads to bilateral impairment of functions of CN IX-XII

Signs include speech difficulties, dysphagia, wasting and fasciculation of the tongue, absent palatal movements, absent gag reflex

Question 7

What are the signs of Pseudo-bulbar palsy?

Answer 7

Upper motor neuron lesion in the corticobulbar pathways in the pyramidal tract leads to impairment of function CN IX-XII and also CN V and VII

Signs include speech difficulties, dysphagia, conical and spastic tongue brisk jaw jerk, emotional lability

Question 8

What is the Olfactory Nerve (CN I) responsible for?

Answer 8

Responsible for sense of smell, which is an important component in the appreciation of taste

Question 9

What might be the principal complaint of the patient if they have something wrong with their Olfactory nerve (CN I)?

Answer 9

A loss of appreciation of taste

Question 10

Give three reasons why sense of smell may be lost.

Answer 10

Trauma

Infection

Ageing

Question 11

What is the name for the loss of sense of smell?

Answer 11

Anosmia

Question 12

How would you identify if a patient had a problem with their Olfactory nerve?

Answer 12

Ask the patient if they have noticed a change in their sense of smell.

If they have, indicate that you would perform an olfactory examination by asking him to smell different scents such has mint or coffee.

Otherwise olfactory nerve is not formally tested.

Question 13

Which nerve is not formally tested (unless there is an indication to do so)?

Answer 13

Olfactory Nerve

Question 14

What is the Optic nerve (CN II) responsible for?

Answer 14

Responsible for the transmission of visual information in addition to acting as the afferent pathway of the light reflex and accommodation reflex.

Question 15

What does the mnemonic AFRO C stand for?

Answer 15

Acuity, Fields, Reflexes, Ophtahlmoscopy/Fundoscopy and colour vision)

Question 16

What is a central scotoma?

Answer 16

Central scotoma is an area of depressed vision that corresponds with the point of fixation and interferes with central vision. It suggests a lesion between the optic nerve head and the chiasm.

Question 17

What are the possible causes of a central scotoma?

Answer 17

Multiple sclerosis - which may cause unilateral or asymmetrical bilateral scotoma

Methyl alcohol - which may cause symmetrical bilateral scotoma

Nutritional causes - which may be due to, e.g. alcohol or tobacco amblyopia, B12 deficiency

Vascular lesions - which may cause unilateral scotoma

Gliomas of the optic nerve - this may cause unilateral scotoma

Simple glaucoma - which may initially cause an off-centre scotoma

Question 18

How far away do you stand from the patient with a Snellen Chart initially?

Answer 18

6 meters

Question 19

How far away do you stand from a patient if they cannot see the Snellen Chart from 6 meters?

Answer 19

3 metres

Question 20

If the patient is unable to read a Snellen Chart at 1 metre what do you document instead?

Answer 20

CF - Counts Fingers
HM - Hand Movements
PL - Perceived Light
NPL - No Perception of Light

Question 21

Why do we conduct visual fields testing?

Answer 21

To assess for defects in central and peripheral vision, and can localise pathology at an anatomical level within the visual pathway

Question 22

What is ophthalmoscopy?

Answer 22

Ophthalmoscopy, also called funduscopy, is a test that allows a health professional to see inside the fundus of the eye and other structures using an ophthalmoscope (or funduscope). It is done as part of an eye examination and may be done as part of a routine physical examination.

Question 23

How do you test for red/green colour vision?

Answer 23

Ishihara Plates

Question 24

What is papillodema?

Answer 24

An enlarged optic disc