Diabetic Retinopathy and Vascular Problems Flashcards
what causes diabetic retinopathy?
chronic hyperglycaemia damages retinal blood vessels and basement membrane
loss of pericytes leads to leakage of blood and ischaemia
presentation of diabetic retinopathy on fundoscopy
dot and blot haemorrhage (microaneurysms) IRMA (dilated and torturous capillaries) hard exudates (lipids) cotton wool spots (fat axons) new vessels grow
what colour is the retina?
transparent
why does the retina appear pink?
reflection of the choroid
what is rubeosis iridis?
new vessel growth
what causes vision loss in diabetic retinopathy?
oedema on fovea
vitreous haemorrhage
scarring/tractional retinal detachment
diagnosis of diabetic retinopathy
fundoscopy
management of diabetic retinopathy
prevention with good HbA1c laser= pan-retinal photocoagulation anti-VEGF vitrectomy rehabilitation for blind/ partially sighted
anti-VEGF examples
ranibizumab
bevacizumab
what is hypertensive retinopathy?
damage to blood vessels due to hypertension
when does hypertensive retinopathy develop faster?
malignant hypertension
presentation of hypertensive retinopathy
copper/ thickened wiring of blood vessels due to thickening and sclerosis
arterioles compress veins as they harder leading to cotton wool spots ischaemia
retinal haemorrhages
disc swelling due to leakage and ischaemia
diagnosis of hypertensive retinopathy
very high BP
fundoscopy
Keith-Wagener classification
management of hypertensive retinopathy
control BP
what artery supplies the inner 2/3rd of the retina?
central artery of the retina
what artery supplies the peripheral 1/3rd of the retina?
choroid
presentation of central retinal artery occlusion (CRAO)
sudden painless loss of vision
cherry red macula
RAPD
pale oedematous retina
why does the macula stay cherry red in CRAO?
supplied by posterior ciliary arteries
which condition is a type of stroke?
CRAO
causes of CRAO
CAD
GCA
embolus from the heart
risk factors for CRAO
age FH smoking alcohol hypertension
management of CRAO
dislodge thrombus= massage, remove fluid, inhaling carbogen
what is brach retinal artery occlusion (BRAO)?
less damage due to blockage of tributary of the central artery of the retina
what is amaurosis fugax?
transient CRAO where it is momentarily blocked
presentation of amaurosis fugax
painless visual loss
curtain coming down <5 minutes
full reocvery
management of amaurosis fugax
refer to stroke clinic
what is Virchow’s triad?
Virchow’s triad:
- endothelial damage (DM)
- abnormal blood flow (BP)
- hypercoaguable state
what causes central retinal vein occlusion (CRVO)?
artery becomes stiff and can press on top of the pliable vein causing it to be blocked
Virchow’s triad- venous thrombosis
what does blockage in a vein cause?
back pressure causing ischaemia and forms haemorrhages and oedema
presentation of CRVO
sudden painless loss of vision
diagnosis of CRVO
fundoscopy
FBC
BP
serum glucose
appearance of CRVO on fundoscopy
haemorrhage dilated torturous vessels swelling unable to make out edges of disc cotton wool spots dark retina
risk factors for CRVO
hypertension lipidaemia DM smoking SLE glaucoma
management of CRVO
laser photocoagulation
intravitreal steroids
anti-VEGF
what is branch retinal vein occlusion (BRVO)?
occlusion of tributary
presentation of BRVO
can be asymptomatic
painless disturbance in vision/ loss of part of field
what is ischaemic optic neuropathy?
occlusion of the optic nerve circulation (posterior ciliary arteries)
presentation of ION
sudden painless visual loss
red flag= young patient with unilateral vision loss/ colour vision loss (MS)
diagnosis of ION
examination= swollen optic nerve, edges fluffy with loss of well-define border
what is GCA/ temporal arteritis?
example of an ION
posterior ciliary artery walls become inflamed and thickened until occluded
what condition is GCA associated with?
polymyalgia rheumatica
presentation of GCA
headache
jaw claudication
scalp tenderness
enlarged temporal arteries (torturous appearance)
patients describe not being able to brush hair, lie on affected side, etc.
malaise
>50
management of GCA
sight-threatening
manage with steroids immediately
what is a vitreous haemorrhage?
bleeding occurring from abnormal vessels
presentation of vitreous haemorrhage
sudden visual loss floaters (fly's/spider's webs in vision) may just see red or black depending on density loss of red reflex eye red laser marks from previous
