retinopathies (HTN / diabetic)

Question 1

what is diabetic retinopathy?

Answer 1

blood vessels in the retina become damaged from prolonged exposure to high blood sugar levels (hyperglycaemia) which causes progressive deterioration in health of retina

Question 2

pathophysiology of diabetic retinopathy

Answer 2

damage to blood vessels =
*micro aneurysms (weakness in wall causes small bulges)

*venous beading (walls of the veins are no longer straight and parallel and look more like a string of beads/sausages)

damage to nerve vessels
*fluffy white patches on retina (cotton wool spots)

intraretinal microvascular abnoramlities (IMRA) dilated and tortuous capillaries in the retina which act like a shunt from A to V

neovascularisation
growth factor are released int retina= development of new blood vessels

Question 3

signs of proliferative diabetic retinopathy

Answer 3

• cotton wool spots
• neovascularisation
• blot haemorrhage
• hard exudate
• micro aneurysm

Question 4

classification of diabetic retinopathy

Answer 4

1) non proliferative / background / pre-proliferative
- mild (micro aneurysm)
- moderate (micro aneurysm, blot haemorrhage, hard exudate, cotton wool spots, venous beading)
- severe: blot haemorrhage, micro aneurysm in 4 quadrants venous beading gin 2, intraretinal microvascular abnormality in any

2) proliferative
- neovascularisation
- vitreous haemorrhage

Question 5

what is diabetic maculopathy?

Answer 5

Macular oedema

Ischaemic maculopathy

Question 6

complications of diabetic retinopathy

Answer 6

Retinal detachment
Vitreous haemorrhage (bleeding in to the vitreous humour)
Rebeosis iridis (new blood vessel formation in the iris)
Optic neuropathy
Cataracts

Question 7

management of diabetic retinopathy

Answer 7

Laser photocoagulation

Anti-VEGF medications such as ranibizumab and bevacizumab

Vitreoretinal surgery (keyhole surgery on the eye) may be required in severe disease

Question 8

hypertensive retinopathy

Answer 8

damage to small blood vessels in retina relating to systemic HTN (chronic HTN / malignant HTN)

Question 9

signs in retina of HTN

Answer 9

1) silver wiring / copper wiring: walls in arterioles become thickened and sclerosed causing increased reflection of light
2) AV nipping (arterioles compresses veins as they cross)
3) cotton wool spots (ischaeima / infarction - damage to nerve fibres)
4) hard exudates (leaking lipids)
5) retinal haemorrhage (damage to vessels rupturing and releasing blood into retina)
6) papilloedema (ischaema of optic nerve= swelling = oedema. = blurring of disc marking

Question 10

HTN retinopathy in summary

Answer 10

• silver wiring
• cotton wool spots
• retinal haemorrhage
• AV nipping
• hard exudates
• papilloedema

Question 11

keith-wagener classification

Answer 11

Stage 1: Mild narrowing of the arterioles
Stage 2: Focal constriction of blood vessels and AV nicking
Stage 3: Cotton-wool patches, exudates and haemorrhages
Stage 4: Papilloedema

Question 12

management of hypertensive retinopathy

Answer 12

• control BP

- control risk factors (smoking and blood lipids)