Retinal Vein and Artery Occlusion Flashcards
(12 cards)
How retinal vein occlusion normally classified?
What is the aetiology for each?
Central retinal vein
Branches of retinal vein
Hemiretinal vein occlusion (not as common)
Central - thrombus formation in the lumen interrupts blood flow
Branches - these most commonly occur at AV crossings. Arterial disease is thus the more common aetiology due to compression.
what features should one look out for in the Hx when retinal vein occlusion is suspected?
- HTN, diabetes, atherosclerosis, CV disease, smoking, glaucoma etc.
- Young patients – Hx of hyper-coagulable state or vasculitis
- Macular oedema – will present with decreased central vision
- Vitreous haemorrhage – floaters throughout visual field
how would retinal vein occlusion present?
Common features: sudden, painless, unilateral loss of vision
Central: vision loss in the entire visual field
Branch: visual loss in one quadrant of the visual field.
Hemi - loss of one half of visual field (whole superior or inferior)
how may central vein occulsion be broken down?
- Non-ischaemic
o Decreased visual acuity (mild to moderate), painless, metamorphosia (Metamorphopsia is a type of distorted vision in which a grid of straight lines appears wavy and parts of the grid may appear blank)
o Dilated tortuous retinal veins
o Retinal haemorrhages in all four quadrants, occasional cotton wool spots, mild optic disc oedema
o Complications
Cystoid macular oedema - Ischaemic
o Decreased visual acuity (severe), painless (unless Neovascular glaucoma has developed)
o RAPD
o Deeper and more extensive haemorrhages than non-ischaemic, widespread cotton wool spots
o Rarely you may develop vitreous haemorrhage
o Collateral vessel, particularly at the optic disc
o Complications
Cystoid macular oedema, neovascularisation (neovascular vessels are typically smaller calibre than collaterals and branch into a net-like vascular network), neovascular glaucoma
how would you investigate someone with retinal vein occlusion?
Basic investigations of their physiological state: BP, FBC, ESR, U+E, Glu, lipids, protein electrophoresis, TFT, and ECG
- Other investigations could include for hyper-coagulable state, infection, auto-antibodies, thrombophilia screen etc.
Eye:
FFA - - FFA (fundus fluorescein angiography)
o All: normal arm to eye time, slow AV phase acutely
o Non-ischaemic: vein wall staining, microaneurysms, dilated optic disc capillaries.
o Ischaemic: as for non-ischaemic, but capillary closure (5–10DD is borderline; >0 is significantly ischaemic), hypofluorescence (blockage due to extensive haemorrhage), leakage (CMO, neovascularization)
OCT (optical coherence tomography)
how would you manage central retinal vein occlusion?
manage underlying medical conditions.
non-ischaemic: where vision has been affected consider Ozurdex (intra-vitreal dexamethasone) or ranbizumab.
Ischaemic without neo-vascularisation - monitor
Ischaemic with neovascularisation - panretinal photocoagulation laser
name some complications of branch retinal vein occlusion
cystoid macula oedema, neovascularisation, recurrent vitreous haemorrhage
how would a central retinal artery occlusion present?
Sudden painless unilateral decrease in VA (not loss of vision)(usually only able to count fingers)
White swollen retina, RAPD, may have visible emboli
when investigating central retinal artery occlusion what are you looking to do?
Causes?
Find the cause and rule out GCA
Causes - GCA, atherosclerosis, carotid artery disease
how would you treat acute central retinal artery occlusion?
Decrease IOP with IV acetazolamide (a carbonic anhydrase inhibitor)
+/- anterior chamber paracentesis.
If GCA - steroids to protect the other eye.
what is common cause of branch retinal artery occlusion?
emboli which will be visible clinically
how will branch retinal artery occlusion present?
sudden, painless unilateral altitudinal field defect
