Eye Strokes: What You Need To Know

Eye strokes, or retinal artery occlusions, are a medical emergency that requires urgent attention. They occur when blood flow to the retina is blocked, usually by a blood clot, causing a sudden change or loss of vision in one eye. This is similar to a stroke in the brain, where a blockage in a blood vessel cuts off the blood supply. In the case of an eye stroke, the blockage affects the retina – a thin layer of tissue at the back of the eye that sends light signals to the brain. Without blood flow, the cells in the retina can start to die within minutes or hours, and permanent vision loss or blindness can occur without quick intervention.

Eye strokes are medical emergencies requiring immediate attention

An eye stroke, or Central Retinal Artery Occlusion (CRAO), is a medical emergency that requires immediate attention. It occurs when there is a blockage in the blood vessels in the retina, usually due to a blood clot or a piece of fatty plaque. This interruption in blood flow can cause a complete or partial loss of vision in one eye, often without any pain.

The retina is a thin layer of tissue at the back of the eye that helps you see by sending light signals to the brain. When blood flow to the retina is blocked, the cells start to die within minutes or hours due to a lack of oxygen, which can result in permanent vision loss or blindness. Therefore, it is crucial to seek immediate medical attention if you experience any sudden changes in your vision, such as blurriness, floaters, darkened areas, or light sensitivity in one eye.

The faster you receive medical care for an eye stroke, the better the chances of preserving your vision. Treatment options include clot-busting medications, eye massage, hyperbaric oxygen therapy, and surgical procedures to inject clot-dissolving medicine directly into the affected artery.

To diagnose an eye stroke, an ophthalmologist will perform an eye exam or review a fundus photo, which is a special image of the internal parts of the eye, including the optic nerve and retina. It is important to note that eye strokes can be early signs of other vascular events, such as ischemic strokes and heart attacks. Therefore, it is crucial to seek immediate medical attention to prevent permanent damage and to assess your risk for future vascular events.

Blockages in the main artery in the retina are called central retinal artery occlusions (CRAO)

CRAO is caused by a blockage, typically a blood clot or cholesterol deposit, in the central retinal artery. This blockage can be the result of various factors, including high blood pressure, aging, diabetes, thicker-than-normal blood, and the use of birth control pills in women.

The symptoms of CRAO include sudden blindness or complete blurring of eyesight in one eye. These symptoms can come on quickly and be very serious. The area of the retina affected by the blocked vessels determines the extent of visual loss. In most cases, CRAO results in severe and permanent vision loss, and even with treatment, eyesight is unlikely to improve.

CRAO is typically diagnosed through a dilated eye examination, which reveals a "cherry red spot" at the centre of the macula, with the surrounding retina appearing pale due to the lack of blood flow. While there is no clinically proven treatment for CRAO, several therapies may be used, including hyperventilation with carbogen, paracentesis, lowering intraocular pressure, and ocular massage. However, these treatments must be administered within a short time window, typically within 4 to 8 hours of the onset of symptoms to have any potential effectiveness.

Blockages in smaller arteries are called branch retinal artery occlusions (BRAO)

An eye stroke is a medical emergency that requires urgent attention. It is caused by a blockage, typically a blood clot, in an artery in the eye. Blockages in the eye can occur when a blood clot or fat deposit gets stuck in the arteries. These blockages are more likely if there is hardening of the arteries (atherosclerosis) in the eye.

Blockages in the main artery in the retina are called central retinal artery occlusions (CRAO) and can result in severe loss of vision. A blockage in a smaller artery is called a branch retinal artery occlusion (BRAO). BRAOs may cause a loss of a section of your visual field, such as your vision to one side. If the affected area is not in the center of the eye or is relatively small, a BRAO may go unnoticed with no symptoms.

The ophthalmic artery is the main artery supplying blood to the eye, and when it is blocked, it produces the most damage. However, about 25% of people who develop CRAO have an extra artery called a cilioretinal artery in their eyes. When CRAO occurs, having a cilioretinal artery can greatly lessen the chances of damage to your central vision, as long as the cilioretinal artery is not affected.

If you or a loved one are experiencing sudden, painless vision change or vision loss in one eye, seek immediate medical care.

Eye strokes can lead to permanent vision loss or blindness

An eye stroke, or retinal artery occlusion, occurs when there is a blockage in the artery that supplies blood to the retina. This blockage is often a blood clot, but it can also be caused by an infection or a build-up of plaque breaking off from another part of the body. The retina is the part of the eye that communicates with the brain to turn light into images, so when blood flow to the retina is interrupted, it can result in vision loss.

Eye strokes are a medical emergency and require urgent attention. They can lead to permanent vision loss or blindness if not treated promptly. The hallmark signs of an eye stroke are sudden and painless vision loss or changes in vision in one eye. These changes can include blurriness, floaters, darkened areas in the field of vision, decreased visual contrast, and light sensitivity. While these symptoms usually come on quickly, they can also appear gradually.

The faster someone receives care for an eye stroke, the more likely they are to experience positive outcomes. Treatments for eye strokes include medications to reduce eye pressure or dissolve blood clots, laser treatment to close leaking blood vessels, and hyperbaric oxygen therapy, which involves breathing pure oxygen in a pressurized chamber to preserve the retina's energy supply and optimize recovery.

It is important to note that having an eye stroke may indicate an increased risk of having a brain stroke, as many of the risk factors are the same for both conditions. Therefore, it is crucial to seek immediate medical attention if you experience any sudden changes in your vision.

Eye strokes can be caused by underlying medical conditions

An eye stroke, or retinal artery occlusion, occurs when something blocks an artery that supplies blood to the retina. The blockage is typically a blood clot, but it can also be caused by a narrowing of the blood vessels in the retina. The risk factors for eye strokes are similar to those of a regular stroke and include underlying medical conditions such as:

• High blood pressure (hypertension)
• High cholesterol (hyperlipidemia)
• Atherosclerosis, or plaque buildup in the arteries
• Previous heart attack or stroke
• Coronary heart disease
• Diabetes or a family history of diabetes
• Being older than 60, especially for men

These underlying medical conditions can cause an interruption of blood flow to the retina, leading to an eye stroke. The retina relies on a steady supply of blood to function properly and send visual signals to the brain. When the blood flow to the retina is blocked or reduced, it can result in permanent damage to the retina and loss of sight.

It is important to note that eye strokes are medical emergencies that require urgent attention. If you or someone you know experiences sudden vision loss or changes in one eye, even if it is temporary, seek immediate medical help.

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