The Eye in Systemic Disease Flashcards
Describe the pathogenesis of diabetic retinopathy
chronic hyperglycaemia
glycosylation of protein/basement membrane
loss of pericytes (cells that wrap around capillaries)
microaneurysm
microaneurysm causes leakage and ischaemia which causes proliferation of blood vessels
What is the earliest sign of diabetic retinopathy?
Microaneurysm
What may diabetic maculopathy be caused by?
Capillary leakage giving rise to chronic macular oedema
Lipid deposition in the macular area
Extensive obliteration of the macular capillaries
Treatments of diabetic eye disease?
Maximise glycemic control
Eye screening
New vessels are indication for laser photocoagulation therapy
If new vessels on the optic disc then pan retinal photocoagulation is carried out which involves laser burns to the peripheral retina
In hypertensive retinopathy the appearance of fundus correlates to ______________________
severity of hypertension and the state of the retinal arterioles
Causes of occlusion of the central retinal artery?
1) Thrombosis in a central retinal artery damaged by atherosclerosis or hypertension (most common)
2) Emboli
3) Inflammatory changes in central retinal artery due to GCA
Cherry red spot?
Occlusion of the central retinal artery
How will the fundus appear in central retinal artery occlusion?
Arteries narrowed and retina is opaque (usually retinal is transparent). A cherry red spot is seen at the fovea as the choroidal vasculature shows up through the thinnest part of the retina.
Symptoms of central retinal artery occlusion
Sudden, painless and profound loss of vision that rarely recovers
Explain the appearance of the funds in central retinal vein occlusion?
Thrombosis causes obstruction to the outflow of blood leading to a rise in intravascular pressure. This results in dilate veins, retinal haemorrhage, cotton wool spots and abnormal leakage of fluid from vessels causing retinal oedema.
Predisposing factors to CRVO?
Increasing age, hypertension, CV disease, diabetes, glaucoma and in younger blood dycrasias (disorder) and vasculitis
What part of the eye can be effected by rheumatoid arthritis? What can happen?
Collagenous coats of the eye (sclera and cornea) or the lacrimal gland
Scleritis and corneal melt
Sjrogens syndrome effects on eyes?
Inflammation of the cornea and conjunctivitis (due to inflammatory and degenerative changes in the lacrimal gland)
Dry eyes
Most patients with sjrogens syndrome have…
another autoimmune condition e.g. rheumatoid arthritis
Symptoms of sjrogens syndrome?
Dry eyes- gritty feeling Dry mouth Dry throat Vaginal dryness Bilateral parotidd enlargement Generalised aches and pains Fatigue Unexplained increase in dental caries
What is sarcoidosis?
Non-caseating granulomatous disease of unknown cause. Multi-system disease.