RVOs + RAOs Flashcards
What is an RVO? What is it divided into?
Retinal vein occlusion. Divided into:
- Branch retinal vein occlusion (BRVO)
- Central retinal vein occlusion (CRVO)
Which of the RVO is more common?
BRVO 3 times more common than CRVO
What are the non-ischaemic examination findings of a CRVO?
reduced visual acuity (mild-to-moderate)
painless
metamorphopsia (i.e., distorted vision in which a grid of straight lines appears wavy and parts of the grid may appear blank)
What are the non-ischaemic fundoscopy findings of a CRVO?
dilated tortuous veins, with retinal haemorrhages in all 4 quadrants
occasional cotton wool spots
mild optic disc oedema
What are the ischaemic examination findings of a CRVO?
Reduced visual acuity (severe); painless (unless neovascular glaucoma (NVG) has developed)
What are the ischaemic fundoscopy findings of a CRVO?
RAPD
deeper and more extensive haemorrhages
widespread cotton wool spots
rarely vitreous haemorrhages
exudative retinal detachment
Chronic
- venous sheathing
- resorption of haemorrhages
- macular pigment disturbance
- collateral vessels (especially at disc)
What are the complication of ischaemic CRVO?
Cystoid macular oedema (CMO)
Neovascularisation
Neovascular glaucoma (NVG)
What are the complication of non-ischaemic CRVO?
Cystoid macular oedema (CMO)
What are the investigations for BRVO?
Cardiovascular assessment esp. BP - HTN is the commonest association with BRVO (up to 75% of patients)
Fundus fluorescein angiography (FFA) : if diagnosis is uncertain to assess ischaemia
OCT : useful for documenting macular oedema
How would a non-ischaemic BRVO with visual acuity > 6/12 be treated at baseline?
Observe
How would a non-ischaemic BRVO with visual acuity 6/12 or less and macular oedema be treated at baseline?
Consider anti-VEGF or Ozurdex
Fundus fluorescein angiography (FFA) if haemorrhages not blocking fovea
How would a non-ischaemic BRVO with visual acuity > 6/12 be treated at 3 months?
Continue treatment (e.g., anti-VEGF monthly or Ozurdex 4 to 6 monthly or observation)
How would a non-ischaemic BRVO with visual acuity 6/12 or less and macular oedema be treated at 3 months?
Continue/commence Tx with anti-VEGF or Ozurdex.
If unresponsive to previous Tx consider modified grid laser if minimal macular ischaemia.
If severe ischaemia, consider observing as improvement unlikely even with Tx
How would an ischaemic BRVO with no neovascularisation be treated?
Observe 3-monthly for 24 months
How would an ischaemic BRVO with neovascularisation be treated?
Sectoral panretinal photocoagulation (PRP)
Intravitreal bevacizumab (off-licence) could also be given in combination with laser
How would a non-ischaemic CRVO with macular oedema be treated?
Consider anti-VEGF or dexamethasone implant (if anti-VEGF not suitable)
Monthly injections of anti-VEGF are given until max visual acuity (VA)
If there is not improvement after 3 injections, the anti-VEGF may be discontinued (but it’s recommended to stop if no improvement after 6 injections)
For Ozurdex retreatment may be required 4 to 6 monthly until visual acuity stable
How would an ischaemic CRVO with neovascularisation and open anterior chamber (AC) angle be treated?
Urgent pan-retinal photocoagulation (PRP) with review at 2 weeks
Consider combined use of bevacizumab (off-licence)
Repeat Tx if neovascularisation of the iris (NVI)/neovascularisation of the angle (NVA) persists
How would an ischaemic CRVO with NVI/NVA with closed angle and raised IOP be treated?
Urgent PRP (pan-retinal photocoagulation) with cyclodiode laser therapy/tube shunt surgery (preferable if angle closure is established)
If IOP normal or normalises with the above therapy consider bevacizumab
If IOP elevated then add topical and med Mx
How would an ischaemic CRVO without NVI/NVA be treated?
If limited follow-up likely and fundus fluorescein angiography (FFA) shows > 30 DA non-perfusion, consider prophylactic PRP
If ischeamic CRVO with macular oedema, can treat with anti-VEGF/dexamethasone, but guarded prognosis should be explained
What is a RAO?
Retinal artery occlusion
An ocular emergence
Why is rapid Tx of an RAO vital?
To prevent irreversible loss of vision
What is the incidence of RAO? Which gender is more likely to be affected?
Incidence = 0.85/100,000/year
M:F = 2:1 (men 2ce as likely to be affected as women)
What are the two types of RAO?
Central retinal artery occlusion (CRAO)
Branch retinal artery occlusion (BRAO)
What are the clinical features of a CRAO?
Sudden painless unilateral reduction in visual acuity (usually CF or worse)
On fundoscopy
-White swollen retina with cherry-red spot at the macular
-Arteriolar attenuation + cattle trucking
-RAPD
-Visible emboli in up to 25%
A cilioretinal artery (present in 30%) may protect part of the papillomacular bundle, allowing relatively good vision
