Diabetic Retinopathy

Question 1

Types of retinopathy

Answer 1

Non-proliferative (NPDR) =
- Mild: 1 or more microaneurysm + dot haemorrhages
- Moderate: microaneurysms, blot haemorrhages, hard exudates, cotton wool spots
- Severe: blot haemorrhages, microaneurysms, venous beading, IRMA
Proliferative (PDR)
Maculopathy

Question 2

Aetiology of diabetic retinopathy

Answer 2

Hyperglycaemia → increased retinal blood flow and abnormal metabolism in retinal vessel walls → damage to endothelial cells and pericytes
Endothelial dysfunction→ increased vascular permeability → exudates
Pericyte dysfunction → microaneurysms
Retinal ischaemia and neovascularisation

Question 3

Epidemiology of diabetic retinopathy

Answer 3

Most common cause of blindness in adults 35-65

Question 4

Symptoms of diabetic retinopathy

Answer 4

Early stages = asymptomatic
Floaters/dark spots in vision
Blurred/distorted vision
Difficulty seeing at night
Sudden loss of vision

Question 5

Features of background diabetic retinopathy

Answer 5

Hard exudates (cheese colour, lipid)
Microaneurysms (“dots”)
Blot haemorrhages

Question 6

Features of pre-proliferative diabetic retinopathy

Answer 6

Cotton wool spots also called soft exudates
Represent retinal ischaemia

Question 7

Features of proliferative diabetic retinopathy

Answer 7

Visible new vessels on disk or elsewhere in the retina
From untreated pre-proliferative retinopathy
(Response to retinal ischaemia, new vessels are more fragile and can bleed anytime, if form in region of macula- can affect acuity and colour vision)

Question 8

Features of maculopathy

Answer 8

Hard exudates near the macula
Same disease as background, but happens to be near macula
This can threaten direct vision (+ acuity and colour)

Question 9

Management of diabetic retinopathy

Answer 9

Optimise glycaemic control, blood pressure and hyperlipidemia
Regular review by ophthalmology

Pan-retinal photocoagulation
Grid photocoagulation
Intravitreal VEGF inhibitors
Vitrectomy

Question 10

Complications of panretinal photocoagulation

Answer 10

50% experience reduction in visual fields
Decrease in night vision
Decrease in acuity
Macular oedema (use OCT to detect)

Question 11

Complications of diabetic retinopathy

Answer 11

Vitreous Hemorrhage: Can cause sudden vision loss.
Tractional Retinal Detachment: May lead to blindness.
Macular Oedema: Causes central vision loss.
Neovascular Glaucoma: Can result in severe pain and vision loss.
Blindness: The ultimate complication in untreated or advanced cases.