Diabetic Retinopathy: Gradual Vision Loss

Question 1

What is diabetic retinopathy?

Answer 1

Gradual loss of vision seen due to hyperglycaemia in diabetic patients.

Question 2

What is the epidemiology of diabetic retinopathy?

Answer 2

Most common cause of blindness in adults aged 35-65.

Question 3

What is the cause of diabetic retinopathy?

Answer 3

Hyperglycaemia is though to cause increased retinal blood flow and abnormal metabolism in the retinal vessel walls.
This precipitates damage to endotherlial cells and pericytes.

Question 4

What is seen on fundoscopy in diabetic retinopathy?

Answer 4

Characteristic exudates

Question 5

What is the pathophysiology of diabetic retinopathy?

Answer 5

Endotherlial dysfunction –> increased vascular permiability –> exudates.

Pericyte dysfunction –> microaneurysms

Neovascularisation –> production of growth factors in response to retinal ischaemia.

Question 6

On fundoscopy, how is Background retinopathy defined?

Answer 6

Micoaneurysms (dots)
Blot haemorrhages < 3
Hard exudates

Question 7

On fundoscopy, how is pre-proliferative retinopathy defined?

Answer 7

Cotton wool spots (soft exudates; ischaemic nerve fibres)
>3 blot haemorrhages
Venous beading/looping
Deep/dark cluster haemorrhages
(More common in T1DM)

Question 8

What is the treatment of pre-proliferative retinopathy?

Answer 8

Laser photocoagulation

Question 9

What is the classification of mild non-proliferative diabetic retinopathy (NPDR)?

Answer 9

1 or more microaneurysm

Question 10

What is the classification of moderate non-proliferative diabetic retinopathy (NPDR)?

Answer 10

Microaneurysms
Blot haemorrhages
Hard exudates
Cotton wool spots, venous beading/looping and intraretinal microvascular abnormalities (IRMA) less severe than in severe NPRD

Question 11

What is the classification of severe non-proliferative diabetic retinopathy (NPDR)?

Answer 11

Blot haemorrhages and microaneurysms in 4 quadrants
Venous beading in at least 2 quadrants
IRMA in at least 1 quadrant

Question 12

What is the classification of proliferative retinopathy (PR)?

Answer 12

Retinal neovascularisation - may lead to vitrous haemorrhage
Fibrous tissue forming anterior to retinal disc
More common in T1DM - 50% blind in 5 years

Question 13

What is Maculopathy?

Answer 13

Based on location rather than severity
Hard exudates and other ‘background’ changes on macula
Check wisual acuity
More common in T2DM