The Eye and Systemic Disease Flashcards
How does the retina appear in diabetic retinopathy?
- White spots are scars from laser treatment
- Yellow stuff is lipid layed macrophages -> called exudates
- Retina should be transparent – the choroid is pink – in DR it looks yellow
Describe the pathogenesis of diabetic retinopathy
- Chronic hyperglycaemia
- Glycosylation of protein/basement membrane
- Loss of pericytes* leads to small microscopic outpouchings of the retina -> microaneurysm
- Microaneurysm can lead to leakage + ischaemia
- Pericyte = contractile cells that wrap around the endothelial cells that line the capillaries and venules throughout the body.
- Ischaemia leads to new vessel formation
Describe some retinal signs of non-proliferative retinopathy
- Microaneurysms / dot + blot haemorrhages
- Hard exudate (this is blot haemorrhages)
- Cotton wool patches (these are just thickened axons)
- Abnormalities of venous calibre
- Intra-retinal microvascular abnormailities (IRMA – this is just a term for venous bleeding)
- Macroaneurysm – small red dot on retina with blank patch around it
Describe the pathophysiology of neovascularization in DR
- Haemorrhage on retina
- Supply demand mismatch – photoreceptors need more oxygen (i.e. they are ischaemic) , so send out signalling molecules leading to neovascularization
- New blood vessels are not surrounded by pericytes -> not competent, leaky, fragile
- New vessel formation brings a massive scarring response
What is rubeosis iridis?
Neovascularization of the iris - you cannot recover from this
What are the three things that diabetic patients lose their vision from?
- Retinal oedema affecting the fovea
- Vitreous haemorrhage
- Scarring/ tractional retinal detachment
How is diabetic eye disease classified according to retinopathy?
- No retinopathy
- Mild
- Moderate
- Severe
- Proliferative retinopathy
The midde three are classed as non-proliferative
How is diabetic eye disease classified according to maculopathy?
- No maculopathy
- Observable maculopathy
- Referable maculopathy
- Clinically significant maculopathy
Give some management options for diabetic retinopathy
- Optimise medical management
- Laser treatment - mismatch in supply in demand – drop the demand by reducing the metabolic rate of the retina i.e. you sacrifice the peripheral retina
- Surgery – vitrectomy
- Rehabilitation (blind/partial sighted)
- Anti-VGEF
Disc neovascularization can be treated with laser treatment.
How does the appearance of the fundus relate to severity of hypertension?
Appearance of fundus correlates to severity of hypertension and the state of the retinal arterioles.
How can the fundus of elderly vs young patient look in terms of hypertensive retinopathy?
Young people can have extensive retinopathy.
Elderly patients with arteriosclerotic vessels often have minimal changes.
NB – atherosclerotic changes look like hypertensive ones.
Give some fundus features of hypertensive retinopathy
- Attenuated blood vessels (narrowed blood vessels) -copper or silver wiring
- Cotton wool spots
- Hard exudates
- Retinal haemorrhage
- Optic disc oedema
Accelerated hypertension
- Who gets it?
- Fundus appearance?
- Vision?
- Particularly in young patients
- Very dramatic fundal appearance
- Can have decreased vision
What is the other name for neovascular glaucoma?
- Precipitating factor?
- Pathology?
- Symptoms?
Rubeotic eye
- Follows a severe retinal vein blockage or severe diabetic eye disease
- Growth factors from an ischaemic retina spread to the anterior chamber, where they meet the trabecular meshwork (drainage system)
- At the same time as blood vessels grow on the drainage system, they grow on the iris
- They block the drainage system to aqueous cannot drain and so pressure in the eye increases
- Pain and inflammation
Sarcoidosis causes inflammation of which part of the eye?
What other eye symptoms can sarcoidosis cause?
Uvea - choroid, ciliary body and iris
Periocular lesions may produce dry eye symptoms, as well as disfiguring lid, periocular, and adnexal lesions
