Retinal artery occlusions are blockages in the artery that brings blood to the retina, the light-sensitive layer of tissue at the back of the eye.

A retinal occlusion, especially a central retinal artery occlusion, is considered a medically emergent condition. When a retinal artery is blocked, the blood build-up can have serious consequences and may even be a risk factor for brain stroke.

Types of Retinal Artery Occlusions

Retinal artery occlusions can affect either the central artery or the smaller blood vessels branching out from it. The former is generally more serious, with graver consequences. People suffering from the latter, on the other hand, are more likely to recover and even keep most of their eyesight.

Central Retinal Artery Occlusion (CRAO)

CRAO is the more serious type of retinary artery occlusion and is a medical emergency. The condition is actually considered an “eye stroke” and may even raise the chances of someone having a stroke to the brain.

This is because the usual cause of CRAO is a blood clot or buildup of cholesterol in the blood vessel. If the blockage dislodges, it can travel through the artery and all the way up into the brain.

Branch Retinal Artery Occlusion (BRAO)

BRAO happens when the blockage occurs in a smaller or branch artery of the retina as opposed to the central one. This is the less serious version of retinal artery occlusion, although it should still be assessed for the likelihood of developing into a brain stroke.

In most cases, however, BRAO is transient and even resolves by itself. This means that most people who get it will not need to get aggressive therapy – an eye doctor will typically assess the situation to determine the best course of action.

Causes of Retinal Artery Occlusions

Most retinal artery occlusions come from a blood clot or embolus (a fatty deposit) in the bloodstream. Such clots or lumps block blood vessels, which means blood cannot go where it needs to deliver oxygen.

Without the oxygen and nutrients it needs to survive, the retina begins to malfunction. Like most parts of the human body when starved of oxygen, it can even die. The result is vision loss, which is one of the most common symptoms of retinal artery occlusions.

Due to the cause of retinal artery occlusions, any condition that makes someone more likely to develop blood clots or an embolus is a risk factor. Below are some things that bring up your chances of developing the condition:

• Coronary heart disease
• Being over 60 years old
• Diabetes
• Obesity
• Smoking
• Atherosclerosis
• Hypertension
• High cholesterol levels
• Blood clotting issues

Some studies also indicate that men are more likely to develop retinal artery occlusions, although women certainly can have the condition as well.

Recognising the Symptoms of Retinal Artery Occlusion

Retinal artery occlusion symptoms are often sudden and dramatic when the occlusion affects the central artery. An example would be your vision suddenly blurring over completely, usually in just one eye (the eye with the artery occlusion).

Another common symptom is abrupt and unexplained loss of vision. This may be partial (where the loss just reduces the field of vision) or total for one eye.

That said, there are cases when the symptom is more gradual, e.g. a progressive degradation of vision that occurs over several weeks. Again, that usually affects just one eye.

The reason for the retinal artery occlusion signs generally being limited to just one eye is that it is highly unlikely for a person to develop a retinal artery occlusion in both eyes at the same time. Even then, there is no certainty that both would present the exact same symptoms.

Get an eye health checkup and assessment today

Retinal artery occlusions are serious issues that require emergency medical care. If you exhibit the symptoms above, you should see your doctor immediately.

The sooner you act, the better your chances of preventing the condition from getting worse or possibly developing into a

life-threatening brain stroke. That being said, it’s important to note that no treatment can reliably restore visual loss from retinal artery occlusions.

Unfortunately, many people who get retinal artery occlusions, particularly CRAO, are likely to suffer permanent vision loss. Those with BRAO are more likely to recover some of their eyesight when the condition resolves, by comparison.

Despite that, it’s vital to get care and continued checkups for the condition. As we noted earlier, this can help with its management and may also avoid even worse complications in the future.

Should you wish to get an assessment from one of our specialists or get an eye screening for problems like this, simply call us to enquire or book an appointment.

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