✍️ classified based on FFA findings
☝️ non-ischaemic
☝️ ischaemic
✍️ this classification is useful predictor of visual outcome and risk of neovascularization.
✅ CRVO clinical picture:
✍️ Non-ischaemic CRVO

👍 symptoms
☝️ dropped VA (mild to moderate) > 6/60
☝️ painless
☝️ metamorphopsia.
👍 signs
☝️ Dilated and tortuous retinal veins
☝️ retinal haemorrhages in all four
quadrants
☝️occasional CWS
☝️ mild optic disc oedema.
☝️ Complication ( CMO)
✍️ Ischaemic CRVO
👍 symptoms
☝️ Dropped VA (severe) < 6/60
☝️ painless (unless NVG has developed).
👍 signs
☝️ Dilated and tortuous retinal veins
☝️ retinal haemorrhages in all four quadrants ( deeper and more extensive)
☝️widespread CWS
☝️ RAPD, widespread CWS
☝️ rarely vitreous haemorrhage
☝️ ERD.
☝️ chronic
• venous sheathing
• resorption of haemorrhages
• macular pigment disturbance
• collateral vessels (especially at disc).
☝️ Complications
• CMO
• Neovascularization (NVI > NVD > NVE)
• neovascular (90 days ) glaucoma (NVG ).
• NVD are typically smaller calibre than collaterals, branch into a net-like vascular network and leak on FFA.
✅ CRVO Investigations
✍️ Lab
🔬


☝️ proteinelectrophoresis
☝️TFT
☝️ CRP, serum ACE
☝️ anticardiolipin, lupus anticoagulant
☝️ autoantibodies (RF, ANA, anti-DNA, ANCA)
☝️ fasting homocysteine
☝️ thrombophilia screen (proteins C and S, antithrombin, factor V)
✍️ ECG
✍️ CXR
✍️ FFA
☝️ Non-ischaemic
• vein wall staining
• microaneurysms
• dilated optic disc capillaries.
☝️ Ischaemic:
• capillary closure (5–10 DD is
borderline
• >10 is significantly ischaemic)
• hypofluorescence (blockage due to extensive haemorrhage)
• leakage (CMO, neovascularization)
✍️ OCT:
allows diagnosis and monitoring of macular oedema.
☝️ substantial retinal thickening
☝️ inner and outer retinal cysts
☝️ SRF at the fovea
🚨 Never forget
✍️ hyperviscosity syndrome should be excluded. If simultaneous bilateral CRVOs
✍️ Ocular ischaemic syndrom should be excluded if gentle digital pressure on the globe produces retinal arterial pulsations (or they occur spontaneously)
✅ Risk factors of CRVO
✍️ Atherosclerosis
✍️ Hypertension
✍️ Hypercholesterolaemia
✍️ hypothyroidism
✍️ Diabetes
✍️ Smoking
✍️ Obesity
✍️ Haematological
☝️ abnormal Protein S, protein C
☝️ antithrombin deficiency
☝️ Activated protein C resistance
☝️ Myeloma
☝️Waldenstrom’s macroglobulinaemia
☝️Antiphospholipid syndrome
✍️ Inflammatory
☝️ Behcet’s disease
☝️ PAN
☝️ Sarcoidosis
☝️GPA
☝️ SLE
✍️ Pharmacological
☝️ Oral contraceptive pill (usually in context of prothrombotic state)
✍️ Ophthalmic
☝️ glaucoma (open or closed-angle)
☝️ Trauma
☝️ Optic disc drusen
☝️ Orbital pathology
🛑 Guidelines for management of CRVO
✅ CRVO non-ischaemic
✍️ If VA ≤6/12 + OCT ≥250 microns, consider
☝️ Ozurdex
☝️ AntiVEGF
✍️ if VA <6/60 or RAPD ( manage
as ischaemic CRVO).
✍️ Retreat with Ozurdex at 4–6mth intervals.
✍️ For AntiVEGF, consider monthly injections for 6–12months , and then as required.
✍️ Can be discharged if stable by 24months
✅ CRVO Ischaemic with no NV
✍️ can be discharged if stable by 24 months
✅ CRVO Ischaemic with neovascularization (angle or iris)
✍️ PRP (1,500–2,000 × 500 microns × 0.05–0.10)
✍️ consider combined use of AntiVEGF
✍️ follow-up every 6 wks
✍️ repeat treatment if NVI/NVA persists
✅ NVG with visual potential
✍️ control of IOP with
☝️ topical agents
☝️ cycloablation
✍️ PRP or AntiVEGF
✍️ atropine and Cyclopento
✍️ shunt surgery
✅ NVG in blind eye
✍️ Keep the eye comfortable in any way
☝️ topical anti glaucoma agents
☝️ CPC
☝️ CCA
☝️ Evisceration