Diabetic eye disease (E&M) Flashcards
Define diabetic retinopathy.
Chronic progressive retinal manifestation of hyperglycaemic vascular damage and neurodegenerative change
What is diabetic retinopathy the main cause of? (2)
- visual loss in people with diabetes
- blindness in people of working age
What is the main mechanism of diabetic retinopathy?
Endothelial dysfunction and retinal ischaemia –> produces factors that increase leakiness –> may lead to macular oedema and neovascularisation (due to EPO production)
What are the two types of diabetic retinopathy?
- non-proliferative (early stage, less severe, moderate visual loss)
- proliferative (more advanced, severe visual loss)
Who does diabetic retinopathy affect?
- eventually occurs to some degree in all patients with DM
- most common cause of visual impairment and blindness in patients aged 25-74
What is the progression of diabetic retinopathy? (4)
- background retinopathy
- pre-proliferative retinopathy
- proliferative retinopathy
- maculopathy
How can you classify diabetic retinopathy? (5)
- no disease visible
- mild non-proliferative diabetic retinopathy (NPDR) - localised swelling of small vessels in retina (microaneurysms)
- moderate NPDR - mild NPDR + small bleeds (dot and blot haemorrhages), leaks (hard exudates) or closure (cotton wool spots) of small blood vessels
- severe NPDR - moderate NPDR + further damage to blood vessels (interetinal haemorrhages, venous beading, intraretinal microvascular abnormalities)
- PDR - new vessel formation or vitreous/preretinal haemorrhage or tractional retinal detachment
What are the clinical features of diabetic retinopathy? (5)
- asymptomatic until very late stages - screening important
- spots/dark strings floating in vision
- blurred vision
- fluctuating vision
- vision loss
What are the features of non-proliferative diabetic retinopathy? (4)
- microaneurysms
- hard exudates
- blot haemorrhages
- cotton wool spots
What are the features of proliferative diabetic retinopathy? (3)
- non-proliferative features (microaneurysms, hard exudates, blot haemorrhages, cotton wool spots)
- retinal neovascularisation
- retinal detachment
What can cause complete vision loss? (2)
- retinal detachment
- vitreous haemorrhage
What are the features of retinal detachment (causes complete vision loss)? (3)
- sudden painless loss of vision
- dense shadow starting peripherally and progressing centrally
- flashers/floaters (vs vitreous haemorrhage has no flashing lights)
What are the features of vitreous haemorrhage (causes complete vision loss)? (3)
- bleeding into vitreous humour
- sudden appearance of spots/floaters - blurred vision
- no flashing lights like in retinal detachment
What are fundoscopy findings of background retinopathy? (3)
- (mild NPDR)
- microaneurysms (red dots)
- blot haemorrhages (leaky vessels)
- hard exudates (cheese-coloured lipid deposits due to leakage)
What are the fundoscopy findings of pre-proliferative retinopathy? (3)
- (moderate/severe NPDR)
- features of background retinopathy (microaneurysms, blot haemorrhages, hard exudates)
- cotton wool spots AKA soft exudates (larger yellow spots - retinal ischaemia)
- haemorrhages
What are the fundoscopy findings of proliferative retinopathy? (2)
- features of NPDR (microaneurysms, blot haemorrhages, hard exudates, cotton wool spots)
- neovascularisation (disc/elsewhere)
- (fibrous tissue forming anterior to retinal disease)
- (vision loss due to retinal detachment)
- (vitreous haemorrhage)
What are the fundoscopy findings of maculopathy?
Background retinopathy (hard exudates/oedema) but near macula –> can threaten vision
What is the difference between moderate and severe non-proliferative retinopathy? (5)
- both have blot haemorrhages + hard exudates (severe:)
- microaneurysms in 4 quadrants
- venous beading in 2+ quadrants
- intraretinal microvascular abnormalities in 1+ quadrant
- cotton wool spots (soft exudates)
What are the risk factors for diabetic retinopathy? (5)
- longer duration of diabetes
- poor glycaemic control
- elevated lipid levels (high cholesterol)
- hypertension
- pregnancy
What are the 1st-line investigations for diabetic retinopathy? (4)
- fundoscopy (fundus photography)
- optical coherence tomography
- fluorescein angiography
- B-scan ultrasonography
What are some differential diagnoses for diabetic retinopathy? (4)
- ocular ischaemic syndrome
- radiation retinopathy
- retinal venous occlusion
- hypertension
How do we generally manage diabetic retinopathy in all patients? (4)
- improve blood glucose
- improve BP control
- improve serum lipid control
- regular review by opthalmology
What is the 1st-line management for background retinopathy?
Annual surveillance + improve glycaemic control
What is the 1st-line management for (severe) pre-proliferative retinopathy? (2)
- pan-retinal photocoagulation (using laser to burn new vessels that form - preventative but can cause black dots on retina)
- if severe/vitreous haemorrhage: vitreoretinal surgery
What is the 1st-line management for proliferative retinopathy? (2)
- pan-retinal photocoagulation (laser)
- intravitreal anti-VEGF therapy
What is the 1st-line management for diabetic maculopathy? (2)
- anti-VEGF (evastin - for oedema)
- grid laser therapy
What is the 1st-line management for cataracts (diabetic retinopathy)? (2)
- NSAIDs and corticosteroids
- pan-retinal photocoagulation before cataract surgery
What are some complications of diabetic retinopathy? (6)
- vitreous haemorrhage
- retinal detachment
- glaucoma
- blindness
- cataract
- macular oedema
Describe the prognosis of diabetic retinopathy.
Chronic progressive disease; visual loss may develop despite treatment
