neuro-ophthalmogy

Question 1

What percentage of sensory fibres to the brain come from the optic nerve?

Answer 1

35%

Question 2

What intracranial disease manifest with neuroophthalmological symptoms and signs?

Answer 2

1. Brain tumour
2. multiple sclerosis
3. cerebral aneurysms
   4.

Question 3

What is the pathway of the afferent neuron from the eye?

Answer 3

Light travels from the retina’s ganglion cells, and synapse at the pretectal nucleus in the midbrain

Question 4

Where do the pretectal neurons synapse?

Answer 4

At the Edinger Westphal nucleus on both sides

Question 5

The efferent pathway is from?

Answer 5

The Edinger Wesphal nucleus to the CN III anfd the ciliary ganglion to the iris sphincter

Question 6

What is the pathway of the dilator pupillae?

Answer 6

1. It is from the posterior hypothalamus
2. To the midbrain then the spinal cord
3. exits at C8-T2
4. Then goes to the superior cervical ganglion
5. The carotid plexus
6. To run with the internal carotid artery
7. To the orbit and the eye

Question 7

Normally the pupil responds more briskly and compltely to?

Answer 7

To light than accommodation

Question 8

NB!!

What causes a dissociation where the pupil responds more to accommodation than light?

Answer 8

1. Dorsal midbrain syndrome
2. Ardie’s pupil
3. Argyl Robertson pupil
4. Any lesion before the chiasm(unilaterally or bilaterally)

Question 9

what is another name for relative afferent pupil defect?

Answer 9

Markus Gunn pupil

Question 11

What is the triad do horners sydrome?

Answer 11

miosis

ptosis

anhydrosis

heterochromia if it begins at birth

Question 12

What does the oculomotor nerve supply?

Answer 12

levator palpabrae superioris

Superior rectus. medial rectus, inferior rectus and the inferior oblique(basically 4/6 of the muscles)

Question 13

What does oculomotor nerve palsy present with?

Answer 13

1. ptosis
2. Abducted and inferior eye
3. fixed, diated pupil
4. and horizontal and vertical diplopia

Question 14

What are the causes of oculomotor nerve palsy?

Answer 14

1. brain tumours
2. intracranial aneurysms
3. head injuries

Question 15

The trochlear nerve supplies the:

Answer 15

Superior oblique only

Question 16

In trochlear nerve plasy, the head is tilted towards which side?

Answer 16

The opposite side of the lesion

Question 17

What is the most common cause of trochlear nerve palsy?

Answer 17

Acquired: closed head injuries- vascular diseases, space occupying lesions and very rarely aneurysms

Question 18

What is myasthenia gravis?

Answer 18

It is a chronic autoimmune disease that presents with ocular complaints 80% of the time

Any patients with unexplained ptosis and unexplained diplopia need Tensilon

Question 19

What is nystagmus?

Answer 19

Rhythmic involuntary to and fro movement of he eyes

Question 20

What does nystagmus depend on?

Answer 20

It depends on the type, speed and the direction(horizontal, vertical or rotary)

Question 21

Define scotoma?

Answer 21

An area of visual loss function in the visual field

Question 22

What is the difference between a absolute scotoma and a partial scotoma?

Answer 22

1. Absolute_ complete loss of vision of the cisual function
2. Realtive- partial loss of the visual function

Question 23

What is a homonymous hemianopia?