Ophthalmology 1 + 2

Question 1

Which parts of the brain are involved in the visual system

Answer 1

• Occipital
• Temporal
• Parietal
• Frontal

Question 2

What is presbyopia

Answer 2

• Refractive error

- The lens is unable to change shape and so the image focusses behind the retina

Question 3

Describe myopia

Answer 3

• Nearsighted

- Image focusses in front of retina/focal plane

Question 4

Describe hypermetropia

Answer 4

• Farsighted

- Image focusses behind retina

Question 5

How to treat myopia

Answer 5

Concave lens

Question 6

How to treat hypermetropia

Answer 6

Convex lens

Question 7

Describe the rods

Answer 7

• High convergence to ganglion cells
• One type (cannot discern colour)
• Very light sensitive
• Widespread distribution in retina
• Broad spectral sensitivity

Question 8

Describe the cones

Answer 8

• Low convergence to ganglion cells
• 3 types (red, blue, green)
• Less light sensitive
• Concentrated in macula
• Narrow spectral sensitivity (so can only work in good light conditions)

Question 9

What does a thinner neuroretinal ring indicate

Answer 9

Glaucoma

Question 10

What cells of the retina do the axons of the optic nerve come from

Answer 10

Ganglion cells

Question 11

What lobe of the brain hosts the primary visual cortex

Answer 11

Occipital

Question 12

What is peri-ventricular leucomalacia

Answer 12

Hypoxic-ischaemic damage of preterm infants in the periventricular white matter

Question 13

Describe simultanagnosia

Answer 13

• Bilateral parietal brain damage from CVA
• Difficulty finding one thing amongst many
• Dorsal stream dysfunctionq

Question 14

Describe achromatopsia

Answer 14

• Bilateral anterior occipital brain damage

- Unable to see colour, everything is grey

Question 15

What lobe of the brain serves the function of attention

Answer 15

Parietal

Question 16

What lobe of the brain hosts our visual library

Answer 16

Occipital

Question 17

What lobe executes action based on vision

Answer 17

Frontal

Question 18

What is visual acuity

Answer 18

The ability of the visual system to resolve (see) a gap between 2 objects

Question 19

What is the visual acuity of someone who is blind/SSI

Answer 19

Worse than 3/60

Question 20

What is the visual acuity for driving vision

Answer 20

Better than or equal to 6/12

Question 21

Describe the pupillary pathway

Answer 21

• Optic nerve
• Pretectal nucleus
• Edinger-Westphal nucleus
• Oculomotor nerve

Question 22

Which muscles constrict the pupil

Answer 22

Circular muscles

Question 23

What causes RAPD

Answer 23

• Optic neuritis
• Anterior ischaemic optic neuropathy
• Tumour pressing on the optic nerve
• Glaucoma

Question 24

What can the retinal reflection test indicate

Answer 24

• Corneal scars
• Cataract
• Vitreous bleeds
• Retinal tumours

Question 25

What does direct ophthalmoscopy examine

Answer 25

- Optic nerve (margin, colour, cup) | - Retina (macula, fovea, blood vessels)

Question 26

What are the potential causes of a swollen disc (pseudo)

Answer 26

- Small discs | - Calcium deposits 'Drusen'

Question 27

What are the potential causes of a genuine swollen disc

Answer 27

- Optic neuritis | - Raised ICP (e.g. by SOL, idiopathic inter cranial hypertension or hydrocephalus)

Question 28

What are the 3 key elements that should be commented on when examining the optic nerve head

Answer 28

1. Margin 2. Colour 3. Size

Question 29

What optic signs can diabetes present with

Answer 29

New blood vessels forming around the optic nerve head

Question 30

What are the 6 extra-ocular muscles

Answer 30

- 2 horizontal recti (medial and lateral) - 2 vertical recti (superior and inferior) - 2 oblique (superior and inferior)

Question 31

Ocular defects in a 3rd cranial nerve palsy

Answer 31

- Vertical diplopia - Eye is down and out - Pupil dilated and ptosis

Question 32

Ocular defects in a 4th cranial nerve palsy

Answer 32

- Oblique diplopia - Head tilt away from side of lesion - Diplopia worse away from side of palsy (if unilateral)

Question 33

Ocular defects in a 6th cranial nerve palsy

Answer 33

- Horizontal diplopia - Worse in far distance - Worse towards the side of palsy if unilateral

Question 34

Causes of a 3rd cranial nerve palsy

Answer 34

Aneurysm

Question 35

Causes of a 4th cranial nerve palsy

Answer 35

- Common after head injury (as nerve is long and thin) | - If bilateral, may be congenital

Question 36

Causes of a 6th cranial nerve palsy

Answer 36

Increased cranial pressure

Question 37

Main cause of blindness in developed countries

Answer 37

Age related macular degeneration

Question 38

Main cause of blindness in low income countries

Answer 38

Cataracts