Visual Defects (hong woon)

Question 1

What are the causes of blurred vision?

Answer 1

Refractive problem of the cornea / lens / shape of eye.
OR
could be a macular problem

Question 2

What are the causes of difficulty seeing in bright light (glare)?

Answer 2

corneal or lens problem

often due to cataract

Question 3

What causes distortion of vision (things look wavy, jumbled up, lines not straight)?

Answer 3

Conditions affecting the retina

e. g.
- wet macular degeneration
- macular hole
- macular pucker
- retinal detachment

Question 4

What conditions cause things to look darker / less colour / paler?

Answer 4

1) Optic nerve diseases
- optic neuritis
- compressive optic nerve disease

2) Condition affecting retina
- wet macular degeneration
- central serous retinopathy.

Question 5

What is the cause of homonymous visual field defects? (i.e.same visual field in lost in both eyes)

Answer 5

optic tracts.

Question 6

What is the cause of a non-homonymous visual field defect?

Answer 6

• retinal problem

- optic nerve problem

Question 7

what is the cause of floaters in the visual field?

Answer 7

Floaters are caused by opacity in the vitreous.
This can be caused by :
vitreous syneresis
posterior vitreous detachment
Vitreous haemorrhage.

Question 8

What is a cataract?

Answer 8

Opacity of the lens.

Can cause blurred vision, glare, change in refraction.

Question 9

What leads to drusen?

Answer 9

Drusen are yellow deposits under the retina, the light-sensitive tissue at the back of the eye. Drusen are made up of lipids, a fatty protein.

When waste products from cones and rods are not removed, leads to drusen.

Question 10

Drusen, RPE pigmentation, RPE atrophy are signs of ….?

Answer 10

Dry ARMD
(dry age related macular degeneration)

*dry ARMD particularly affects reading vision.

Question 11

What is phacoextraction with lens implant used to treat?

Answer 11

cataract

Question 12

What could be the cause of sudden loss of vision in one eye?

Answer 12

1) Embolic
e. g. central retinal artery occlusion.
2) Giant cell arterititis (medium/larger arteries of head get inflamed)

Question 13

Case :
blurred vision in left eye.
noticed when covering right eye when putting on makeup.
things in centre look crumpled.

Answer 13

Distorted vision:
Metamorphosia - symptom of distortion of retina.

Differential diagnosis:

• wet macular degeneration
• macular hole
• macular pucker
• retinal detachment

Question 14

What is a common cause of severe, rapid visual loss?

Answer 14

Wet age related macular degeneration