The Eye in Systemic Disease Flashcards
what is the pathogenesis of diabetic retinopathy?
- chronic hyperglycaemia
- glycosylation of basement membrane
- loss of pericytes
- microaneurysm
in what ways can a microaneurysm cause problems?
leakage and ischaemia
signs of non-proliferative retinopathy?
- microaneurysms (dot + blot haemorrhages)
- hard exudates
- cotton wool patches
- abnormalities of venous calibre
- intra-retinal microvascular abnormalities
where can new vessels grow in diabetic retinopathy?
- grow in disc
- grow in the periphery
- grow on iris if ischaemia is severe
what is rebeosis iridis?
new blood vessels forming on the iris
in what 3 ways can diabetic patients lose vision?
- retinal oedema affecting the fovea
- vitreous haemorrhage
- scarring/ tractional retinal detachment
what are the 5 classifications of retinopathy?
- no retinopathy
- mild
- moderate
- severe
- proliferative retinopathy
what are the 4 classifications of maculopathy?
- no maculopathy
- observable maculopathy
- referable maculopathy
- clinically significant maculopathy
what surgery can be performed to control growth of new vessels in diabetic retinopathy?
vitrectomy
features of hypertensive retinopathy?
- attenuated blood vessels
- cotton wool spots
- hard exudates
- retinal haemorrhages
- optic disc oedema
what can happen around the macula which indicates accelerated hypertension?
macular star, hard exudates heading out from macula
in what age group does accelerated hypertension tend to affect?
young patients
how does a CRAO present?
sudden painless loss of vision
how much is vision affected in CRAO?
very profound loss of vision
what area of the retina does the retinal nerve fibre layer not become swollen and what sign does this give rise to?
not swollen at fovea, this gives rise to the cherry red spot
how does the retina appear in a CRAO?
retina is pale, blood vessels are broken up, cherry red spot
how does the retina appear in a CRVO?
blot haemorrhages, hard exudates, retina is darker than normal
extraocular features of thryoid eye disease?
- proptosis
- lid signs- retraction, oedema, lag
- restrictive myopathy
ocular signs of thryoid eye disease in anterior segment?
- chemosis
- injection
- exposure
- glaucoma
ocular signs of thryoid eye disease in posterior segment?
- choroidal folds
- optic nerve swelling
what is the most common cause of unilateral and bilateral proptosis?
autoimmune thyroid disease
how is thyroid eye disease managed?
- control of thyroid dysfunction
- lubricants
- surgical decompression
if someone has thyroid disease, what puts them at a much higher risk of developing thyroid eye disease?
smoking
what can RA cause in the eye?
- dry eyes
- scleritits
- corneal melt
what is the triad of Sjogrens syndrome?
- dry eye
- dry mouth
- RA
what part of the eye does Sjorgens affect?
lacrimal glands
in what direction does the lens dislocate in Marfans?
upwards
how does a dislocated lens present and how is it managed?
sudden profound loss of vision, corrected surgically
what are the features of Stevens-Johnson syndrome in the eyes?
Symblepharon
occlusion of lacrimal glands
corneal ulcers
what is symblepharon and what does it lead to?
sticking together of the fornice, causes tight band of scaring
