Central retinal vein occlusion (CRVO) is a blockage of the main vein that drains blood from the retina. It can cause sudden, painless loss or blurring of vision in one eye.
Causes and Features
The blockage is usually related to clot formation where the central retinal vein passes through the optic nerve, often in the presence of systemic risk factors such as hypertension, diabetes, or cardiovascular disease. Fundus examination typically shows widespread retinal haemorrhages, venous engorgement, and macular swelling.
- More common in older adults and those with vascular risk factors
- Can be classified as non-ischaemic or ischaemic based on severity
- Macular oedema is a major cause of visual impairment
- Neovascularisation may develop in severe cases, increasing the risk of glaucoma
Management
Treatment focuses on managing macular oedema and preventing complications, often using intravitreal injections of anti-VEGF drugs or corticosteroids. Control of systemic risk factors and regular monitoring for new vessels on the retina or iris are also important.
- Visual prognosis is variable and depends on initial severity and response to treatment
- Fluorescein angiography and OCT imaging guide classification and management
- Panretinal photocoagulation may be indicated if extensive ischaemia leads to neovascularisation
- Collaboration with primary care or cardiology helps optimise blood pressure, glucose, and lipid control
