Vascular Occlusions Flashcards
(101 cards)
What is the second most common retinal vascular disease?
RVO (retinal vein occlusions)
What is more common BRVO or CRVO?
BRVO
Why does a BRVO happen?
Venous compression by an artery which causes turbulent blood flow, endothelial damage and then thrombosis —> OCCLUSION
What is the main age occurrence of BRVOs?
60 years
What are some RF of BRVO?
- Systemic HTN
- DM
- smoking
- cardiovascular disease
- glau history
- previous RVO in either
- inflammatory condition
What is a protective factor of BRVO ?
Vein crosses artery instead of artery crossing a vein
What are symptoms of BRVO?
- Sudden painless loss of vision
- Can be asymptomatic
- If macula covered, sector field defect
Where are 66% of cases of BRVO on the retina ?
Superior temporal
In an acute stage of BRVO, what will you observe ?
- Flame haemorrhages
- dilated and tortuous veins
- retinal oedema
- CWS
- normally respect the horizontal mid line
What signs may you see with a px who has chronic stage BRVO?
- hard exudates
- vascular sheathing (appearing white)
- macula pigment
- collateral vessel formation
- retinal ischameia
What is collateral vessel formation?
Small, tortuous vessels that cross horizontal line to drain into unaffected quadrant
Where would retinal ischaemia occur in chronic BRVO?
Downstream to the occlusion
What does retinal ischaemia result due to BRVO?
Upregulation of VEGF + increased vessel permeability + macula oedema
Is this a chronic or acute stage BRVO?
Chronic (substantial amount of exudate)
What can you note that is similar in these two pictures in relation to the BVs?
Vascular sheathing (that white appearance)
What is the main cause of visual loss in BRVO?
Chronic macula oedema
What is an epiretinal membrane?
A membrane forming on the surface of the retina
What are six complications of BRVO?
- Chronic macula oedema
- Exudates
- Haemorrhages
- Epiretinal membrane
- neovasc
- RD (rare)
Why does neovasc occur?
Unregulation of VEGF
When would neovasc occur in BRVO?
ONLY if a large area of retina id ischameic
What type of RD will occur even though it is rare?
Tractional or rhegmatogenous
How long would it take macula oedema to resolve?
12 months in 40% if cases
What % of eyes will maintain a va <6/12?
50%
What % of eyes will have a va <6/60?
25%