CENTRAL RETINAL
ARTERY OCCLUSION
(CRAO)
Sudden Loss of vision
Painless
Painful
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•
•
•
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Central retinal artery occlusion
Central retinal vein occlusion
Retinal detachment involving
macula
Massive vitreous haaemorrhage
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•
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Acute angle closure glaucoma
(Acute congestive glaucoma)
Acute uveitis (irodocyclitis)
Chemical injuries to the eye
Mechanical injuries to the eye
Introduction
◦ First described by von Graefes in 1859
◦ Acute stroke of the eye
◦ Ophtalmic emergency
◦ Atherosclerotic / embolism
von Graefes A. Ueber Embolie der Arteria centralis retinae als Ursache plotzlicherErblindung. Arch Ophthalmol 1859; 5: 136–157.
Rumelt S, Dorenboim Y, Rehany U. Aggressive systematic treatment for central retinal artery occlusion. Am J Ophthalmol1999; 128: 733–738.
Vu H, Keeffe J, McCarty C, Taylor HR. Impact of unilateral and bilateral vision loss on quality of life. Br J Ophthalmol 2005; 89: 360–363.
Epidemiology
◦ 1 in 100,000 people
◦ 80% of patients having a visual acuity (VA) of 20/400 orworse
Anatomy
Anatomy
Hayreh SS. Anatomy and physiology of the optic nerve head.Trans Am Acad Ophthalmol Otolaryngol 1974; 78: OP240–OP254.
Pathophysiology
A thrombus is a blood clot in the vascular system (circulatory system). It
stays attached to the site where it was formed and impedes blood flow.
Under these circumstances, a person is said to be experiencing a
thrombosis.
A thrombus is more likely to occur in people who are immobile, and who
are genetically predisposed to blood clotting.
A thrombus can also form if an artery, vein, or surrounding tissue is
damaged.
An embolus is anything that travels through
the blood vessels until it reaches a vessel that is
too small to let it pass.
When this happens, the blood flow is stopped
by the embolus.
An embolus is often a small piece of a blood
clot that breaks off (thromboembolus).
Risk Factors
◦ Risk factors:
◦ hypertension,
◦ diabetes mellitus,
◦ Heart diseases
◦ smoking tobacco
◦ Alcohol consumption
◦ Hyperlipidemia (Fat in blood)
History
◦ Sudden,
◦ Painless monocular vision loss
◦ Snellen VA of counting fingers or worse
◦ Family history of cerebrovascular and cardiovascular disease, diabetes, hyperlipidaemia, transient ischaemic
events, such as transient monocular blindness
Ocular Evaluation:
Funduscopic of CRAO
◦ Cherry-red spot (90%),
◦ Retinal arterial attenuation
◦ Optic disk oedema
◦ Optic disc Pallor
Management
◦ Attempt to restore ocular perfusion to the CRA.
Varma, D. D., Cugati, S., Lee, A. W., & Chen, C. S. (2013). A review of central retinal artery occlusion: clinical presentation and management. Eye, 27(6), 688-697.
Ocular massage
Ocular massage is performed by digital massage to apply ocular
pressure with an in and out movement to dislodge a possible
obstructing embolus
Repeated massage with 10 – 15 sec of pressure followed by sudden
release is recommended
This procedure can produce retinal arterial vasodilatation, thereby
improving retinal blood flow
Hyperbaric
oxygen
Mixture of 95% oxygen and 5% CO2 can be provided to induce vasodilatation
and improve oxygen
AC paracentesis
• withdrawal of a small amount of aqueous fluid from the eye
• It causes a sudden decrease in IOP, possibly causing the arterial
perfusion pressure behind the obstruction to force an obstructing
embolus downstream.
Other therapies
◦ Intravenous acetazolamide and mannitol, plus anterior chamber paracentesis, followed by withdrawal of a
small amount of aqueous fluid from the eye to increase retinal artery perfusion pressure by reducing
intraocular pressure.
Varma, D. D., Cugati, S., Lee, A. W., & Chen, C. S. (2013). A review of central retinal artery occlusion: clinical presentation and management. Eye, 27(6), 688-697.