[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Conditions](https://durgical.com/en/conditions/) › Central retinal artery occlusion [Conditions](https://durgical.com/en/conditions/) · [Ophthalmology and ENT](https://durgical.com/en/conditions/) # Central retinal artery occlusion A sudden blockage of the main artery of the retina that causes painless loss of vision in one eye. It is an eye stroke and a medical emergency. Updated 2026-11-01 ## Structures involved Tap one to see what it is and open it in 3D. - [Central retinal artery](https://durgical.com/en/anatomy/central-retinal-artery/) - [Retina](https://durgical.com/en/anatomy/retina/) - [Ophthalmic artery](https://durgical.com/en/anatomy/ophthalmic-artery/) - [Optic disc](https://durgical.com/en/anatomy/optic-disc/) - [Macula](https://durgical.com/en/anatomy/macula/) - [Internal carotid artery](https://durgical.com/en/anatomy/internal-carotid-artery/) - [Carotid bifurcation](https://durgical.com/en/anatomy/carotid-bifurcation/) - [Optic nerve](https://durgical.com/en/anatomy/optic-nerve/) ## In the clinical exam - [Fundoscopy: the optic disc, papilledema and retinopathy](https://durgical.com/en/clinical-exam/fundoscopy-the-optic-disc-papilledema-and-retinopathy/) ## Why it happens - [Infarction: red vs white, and what decides the damage](https://durgical.com/en/general-pathology/infarction-red-vs-white-and-what-decides-the-damage/) - [Systemic (arterial) thromboembolism](https://durgical.com/en/general-pathology/systemic-thromboembolism/) - [Retina: the ten layers, rods and cones](https://durgical.com/en/histology/retina-the-ten-layers-rods-and-cones/) ## What it is Sudden blockage of the [central retinal artery](https://durgical.com/en/anatomy/central-retinal-artery/), the branch of the [ophthalmic artery](https://durgical.com/en/anatomy/ophthalmic-artery/) that feeds the inner retina, causing abrupt, painless, severe loss of vision in one eye. It is considered a form of ischaemic stroke. ## Who gets it Uncommon, mainly in people over 60 with vascular risk factors. Because hypertension, diabetes and atrial fibrillation are common and often poorly controlled in Latin America, these patients share the high stroke and heart-attack risk seen elsewhere. ## Causes - Embolus from an atherosclerotic plaque in the carotid artery (cholesterol, platelet-fibrin or calcific emboli) - Cardiac embolus: atrial fibrillation, valve disease or infective endocarditis - Giant cell arteritis (arteritic form) in older adults - Less often thrombosis, vasculitis, hypercoagulable states or sickle cell disease ## Risk factors - Age over 60 - Arterial hypertension, diabetes and dyslipidaemia - Smoking - Carotid artery stenosis - Atrial fibrillation and other cardiac sources of emboli ## Pathophysiology The central retinal artery is an end artery: when it is blocked, the inner retinal layers lose their only blood supply and start to die within minutes to a few hours. The swollen, ischaemic retina turns pale, while the fovea, which is thin and fed by the [choroid](https://durgical.com/en/anatomy/choroid/), keeps its red colour and stands out as a cherry-red spot. A cilioretinal artery, present in some people, can spare central vision. ## Symptoms and signs - Sudden, painless, severe loss of vision in one eye, often to counting fingers or worse - Sometimes preceded by brief episodes of transient monocular vision loss (amaurosis fugax) - Relative afferent pupillary defect (Marcus Gunn pupil) in the affected eye - Fundus: pale, swollen retina with a cherry-red spot at the [macula](https://durgical.com/en/anatomy/macula/) and narrowed arteries, sometimes a visible embolus ## Red flags - Any sudden painless monocular vision loss: treated as a stroke and referred at once - Headache, jaw pain on chewing, scalp tenderness or raised ESR/CRP in an older adult (giant cell arteritis threatens the other eye) - New neurological deficits (weakness, speech problems) together with the vision loss - Irregular pulse or fever with a heart murmur (cardiac source of emboli) ## Diagnosis **Clinical** Visual acuity, pupil examination for an afferent defect, and dilated fundoscopy showing the pale [retina](https://durgical.com/en/anatomy/retina/) with a cherry-red spot. Questions about giant cell arteritis symptoms in every older patient. **Tests** Urgent ESR and CRP (with platelet count) to look for giant cell arteritis; glucose, lipids and blood count; ECG and cardiac rhythm monitoring for atrial fibrillation. **Imaging** Optical coherence tomography and fluorescein angiography confirm the retinal ischaemia. As for any stroke: carotid duplex ultrasound or CT/MR angiography, brain MRI to look for silent infarcts, and echocardiography. ## Differential diagnosis - Central retinal vein occlusion (haemorrhages in all four quadrants) - Retinal detachment (floaters, flashes and a curtain-like shadow) - [Vitreous](https://durgical.com/en/anatomy/vitreous-body/) haemorrhage - Anterior ischaemic optic neuropathy, arteritic or non-arteritic - Optic neuritis or a stroke of the occipital [visual cortex](https://durgical.com/en/anatomy/cuneus/) ## Goal of treatment Treat it as an acute stroke: restore flow when possible within a very narrow time window, rule out and treat giant cell arteritis, and find and control the source of emboli to prevent stroke and heart attack. ## Treatment **Acute** Urgent referral to a stroke centre or ophthalmology emergency service; some centres consider intravenous thrombolysis within the first hours, while evidence is still being studied. **Medical** If giant cell arteritis is suspected, systemic glucocorticoids are started immediately, without waiting for biopsy, to protect the other eye. **Medical** Secondary prevention as for ischaemic stroke: antiplatelet agents or anticoagulants for atrial fibrillation, statins, and control of blood pressure and glucose. **Surgical** Carotid endarterectomy or stenting when a significant symptomatic carotid stenosis is found. **Follow-up** Follow-up for neovascularisation of the [iris](https://durgical.com/en/anatomy/iris/) or angle (risk of neovascular glaucoma) and vascular risk factor control. ## Complications - Permanent severe vision loss in the affected eye - Neovascularisation of the iris and neovascular glaucoma - Stroke or myocardial infarction in the following weeks to years - Loss of vision in the other eye in untreated giant cell arteritis ## Prognosis Most eyes keep poor vision; better recovery occurs when a cilioretinal artery spares the macula or when the blockage is partial or brief. The event signals high cardiovascular risk, and the long-term outlook depends on controlling it. ## Prevention - Control of hypertension, diabetes, lipids and smoking - Anticoagulation in atrial fibrillation when indicated - Prompt assessment of transient monocular vision loss (amaurosis fugax) ## Test yourself Think of the answer, then tap the question to see it. ## What is the classic fundus finding in central retinal artery occlusion? A pale, swollen retina with a cherry-red spot at the fovea and narrowed arteries. ## Why does the fovea look cherry-red in central retinal artery occlusion? The fovea has no inner retina and is fed by the choroid, so its normal red colour shows through against the pale ischaemic retina around it. ## Which blood tests are urgent in an older adult with sudden monocular vision loss? ESR and CRP, to look for giant cell arteritis, which needs immediate glucocorticoids to protect the other eye. ## What is the most common source of emboli in central retinal artery occlusion? Atherosclerotic plaque in the ipsilateral carotid artery; cardiac emboli such as from atrial fibrillation are next. ## Why is central retinal artery occlusion managed like a stroke? It is an ischaemic event of central nervous system tissue that shares the causes of stroke and signals a high risk of later stroke and heart attack. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/conditions/central-retinal-artery-occlusion/) ## Related conditions - [Carotid artery stenosis](https://durgical.com/en/conditions/carotid-artery-stenosis/) - [Giant cell arteritis](https://durgical.com/en/conditions/giant-cell-arteritis/) - [Atrial fibrillation](https://durgical.com/en/conditions/atrial-fibrillation/) - [Ischaemic stroke](https://durgical.com/en/conditions/ischaemic-stroke/) - [Transient ischaemic attack](https://durgical.com/en/conditions/transient-ischaemic-attack/) - [Retinal detachment](https://durgical.com/en/conditions/retinal-detachment/) - [Arterial hypertension](https://durgical.com/en/conditions/arterial-hypertension/) - [Infective endocarditis](https://durgical.com/en/conditions/infective-endocarditis/) Educational information, not medical advice. For any symptom, see a health professional. Sources: [Retinal artery occlusion: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/001028.htm) (MedlinePlus, US National Library of Medicine, 2026); [Eye emergencies: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/000054.htm) (MedlinePlus, US National Library of Medicine, 2026). [← All conditions](https://durgical.com/en/conditions/) ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/conditions/central-retinal-artery-occlusion/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/conditions/central-retinal-artery-occlusion/