diabetic retinopathy

Question 1

pathophysiology of diabetic retinopathy

Answer 1

hyperglycaemia -> basement membrane thickening, loss of pericytes, endothelial cell damage

-> microaneurysms , vascular permeability, capillary occlusion, neovascularisation

Question 2

stages of diabetic retinopathy

Answer 2

1. non-proliferative
2. proliferative

Question 3

features of non-proliferative dm retinopathy

Answer 3

• microaneurysms
• retinal heamorrhages
• hard exudates

Question 4

features of proliferative diabetic retinopathy

Answer 4

proliferation of new and fragile BV that bleed into vitreous -> vision loss

Question 5

classification of non-proliferative DR

Answer 5

1. mild - at least 1 microaneurysm
2. moderate - more microaneurysms, haemorrhages and hard exudate, cotton wool spots
3. severe - 4:2:1 - either:

• > 20 haemorrhage in 4 quadrants
• venous bleeding in 2
• intraretinal microvascular abnormalitis in 1

Question 6

what are cotton wool spots

Answer 6

nerve fibre layer infarctions

Question 7

complications of proliferative retinopathy

Answer 7

vitreous haemorrhage
tractional retinal detachment

Question 8

classification of proliferative diabetic retinopathy

Answer 8

• early - new vessels less than 1/3 of disc area, no vitreous haemorrhage or retinal detachment
• high risk - any of:

1. neovascularisation of disc 1/3 or more
2. vitreous haemorrhage / retinal detachment
3. neovascularisation elsewhere 1/2 or more disc area with vitreous / preretinal haemorrhage

Question 9

what is diabetic macular oedema

Answer 9

complication of diabetic retinopathy
fluid and protein deposit under the macula -> thicken and swell

classified as focal / diffuse
* focal - foci of vascular abnormalities (microaneurysms)
* dilated capillaries in retina

Question 10

clinical features of diabetic retinopathy

Answer 10

asymptomatic
blurred vision
floaters
dark areas in visual field
vision loss

Question 11

ix for diabetic retinopathy

Answer 11

dilated eye exam

flurescein angiography and optical coherence tomography - provide details about retinal and macular thickness, oedema and blood flow

Question 12

mx of dr

Answer 12

1. control diabetes
2. laser photocoagulation for PDR and DME (oedema)
3. anti-VEGF - ranibizumab/aflibercept
4. steroids
5. virectomy in severe cases

Question 13

Answer 13

panretinal laser coagulation

Question 14

Answer 14

pre-prolif DR