Retinopathy - Diabetic, Hypertensive

Diabetic Retinopathy

• Hyperglycaemia leads to damage of small retinal vessels and endothelial cells – This makes the vessels more leaky, therefore leading to blot haemorrhages and hard exudates (deposits of lipids in the retina)

• Damage to nerve fibres cause fluffy white patches to form – Cotton wool spots

• Neovascularisation – VEGF released into the retina

Classified into:

• Non-proliferative – No neovascularisation

• Proliferative – With neovascularisation

Fundoscopic findings:

• Mild disease – Micro-aneurysms (Dots), Hard exudates, Blot haemorrhages

• Severe disease – Cotton wool spots, Large blot haemorrhages

Complications:

• Retinal detachment

• Vitreous haemorrhage

• Optic neuropathy

• Cataracts

• Rubeosis iridis - this is a serious complication where new vessels grow on the iris and anterior chamber due to the release of VEGF. These vessels can raise IOP, therefore leading to secondary glaucoma. It's important to measure IOP in these patients.

Hypertensive Retinopathy

• Damage to retinal vessels due to systemic HTN – Can be a result of chronic hypertension or can develop quickly as a result of malignant hypertension

• Silver wiring is where arteriole walls become thickened and sclerosed, causing increased reflection of the light

• AV Nicking is where stiff arterioles compress onto veins as they cross over

• Damage to nerve fibres cause fluffy white patches to form – Cotton wool spots

• Damage to retinal small vessels and endothelial cells – This makes the vessels more leaky, therefore leading to blot haemorrhages and hard exudates (deposits of lipids in the retina)

• Papilloedema due to ischaemia to optic nerve, resulting in oedema