Diabetic Retinopathy

Question 1

What is the pathogenesis of diabetic retinopathy?

Answer 1

Chronic hyperglycaemia damages vessel walls causing microaneurysms. These cause ischaemia which stimulates formation of poorly functioning capillaries which can haemorrhage filling the vitreous cavity with blood.
This can progress to fibrosis and tractional retinal detachment.

Question 2

How does diabetic retinopathy cause visual loss?

Answer 2

Vitreous haemorrhage

Fibrosis and tractional retinal detachment

Question 3

What eye problems are diabetics at elevated risk of?

Answer 3

Diabetic retinopathy
Cataract
Glaucoma

(acute hyperglycaemia can cause visual blurring)

Question 4

What 5 signs are you looking for on fundoscopy in diabetic retinopathy?

Answer 4

Microaneurysms (small red dots)

Hard exudate (well defined white patches)

Cotton wool patches (poorly defined white patches)

Vein abnormalities (irregular or inflated veins)

New vessels

Question 5

What are hard exudates?

Answer 5

Lipid breakdown products

Question 6

What are cotton wool patches?

Answer 6

Ischaemic nerve fibres

Question 7

What are the two classifications of diabetic retinopathy?

Answer 7

Non-proliferative (no new vessel formation)

Proliferative (new vessel formation)

Question 8

How often are diabetic patients screened for retinopathy?

Answer 8

Annually

Question 9

What diabetic patients are screened more regularly and why? How regularly are they seen?

Answer 9

Pregnant women seen every 3 months

Retinopathy tends to accelerate in pregnancy

Question 10

What is diabetic retinopathy treated? How to these treatments work?

Answer 10

Laser (destroys ischaemic tissue to stop body wanting to make more vessels)

Anti-VEGF injections (blocks body’s signal to produce more vessels)