Retinal artery occlusion is the medical term for a blood clot that forms in the arteries that supply your retina with blood. The retina is a structure in the back of your eye that is responsible for sight, and if its blood flow is cut off, you will lose your vision. Here's what you need to know about this scary condition. 

What causes it?

Retinal artery occlusion has many possible causes, just like blood clots in other parts of your body. One of the most common is high blood pressure: about two thirds of people with retinal artery occlusion have high blood pressure. Diabetes, disease of the heart valves, and artherosclerosis are also associated with developing these clots. 

You can still get a clot even if you don't have high blood pressure, diabetes, or heart disease. The condition can also be caused by tumors, trauma (like getting punched in the eye), oral contraceptives, pregnancy, anesthesia, migraines, or many other factors. 

What are the symptoms?

If you develop a retinal artery occlusion, your first symptom will be sudden vision loss. This isn't painful, and it usually only happens in one eye. It's possible to get a clot in both eyes simultaneously, but this only happens about 1% of the time. Most patients will still be able to see light and will be able to count fingers, but some patients will completely lose their vision. 

How common is it?

Retinal artery occlusion is rare among the general population. Studies have shown that between 0.1% and 0.7% of the population will develop one of these clots. Among some groups of people, they are much more common, for example, among seniors. 1.3% of people over 65 will develop a retinal artery occlusion. It's also more common among people who have diabetes, high blood pressure, or other risk factors for the condition. 

Can it be treated?

There are many possible treatments for retinal artery occlusion, but for them to be effective, treatment must be started as soon as possible. First, doctors will try to lower the pressure inside your eye. The lowered pressure allows your arteries to dilate, which will allow blood to get past the clot and into your retina. To do this, doctors will massage your eyeball, and if that doesn't work, they will use a needle to remove some of the fluids inside your eye. 

Medications can also be given that will help to break up the clot. These only help if they are given within the first few hours after vision loss occurs, and they aren't effective on all types of clots. 

Sometimes, hyperbaric oxygen therapy can be used, but only after other treatments have been attempted. If your hospital doesn't have one of these machines, you will need to be transported somewhere else which will waste valuable treatment time. 

Is the blindness permanent?

The blindness will be permanent if you don't seek treatment, so getting to the hospital quickly is essential. Even so, many people who receive emergency medical treatment don't regain their eyesight. Studies have shown that about 26% of these people will see no improvement in their vision. 35% will see only minor improvements, while 21% will experience a significant restoration of their vision.

Retinal artery occlusion is a serious condition that can cause vision loss or complete blindness in one or both eyes. It is caused by many preventable or manageable conditions such as high blood pressure or diabetes, so seeing your ophthalmologist regularly and living a healthy lifestyle can help protect you. If you suddenly lose vision in one of your eyes, you need to go to the hospital right away for emergency treatment.