What is amaurosis fugax?

Amaurosis fugax is a temporary loss of vision, usually in just one eye, that lasts from seconds to minutes. It is also called episodic blindness. This is a rare problem. If it does happen, it can be treated to prevent a permanent loss of vision. It may also be a warning sign of something more serious, such as a stroke. Sudden blindness in one eye is an emergency.

What is the cause?

The most common cause of temporary vision loss is reduced blood flow to your eye. You have a large blood vessel on each side of your neck that brings blood from your heart to your eyes and brain. Fatty deposits called plaque may build up in blood vessels and make them more narrow. Small pieces of plaque may break off from the wall of a blood vessel and block blood flow to your eye. When the blood vessels are blocked or too narrow, it can cause temporary blindness. Diabetes, smoking, high blood pressure, and high cholesterol can cause problems in the blood vessels in your neck.

Other possible causes of temporary blindness include:

• Migraine headaches, which can cause spasms and narrowing in the blood vessels leading to your eyes.
• Acute angle-closure glaucoma, which causes a sudden rise in the pressure in usually just one of your eyes.

What are the symptoms?

The most common symptom is sudden blindness in one eye that goes away within seconds or minutes. It is often described as seeing a curtain or a shade pulled down over one eye. It is not painful. You can usually see fine out of the other eye.

How is it diagnosed?

Your healthcare provider will ask about your symptoms, examine your eyes, and do tests to identify the cause. Tests you may have are:

• Blood tests
• An ultrasound, which uses sound waves to show pictures of the blood vessels in your neck to look for narrowing or blockages
• CT scan, which uses X-rays and a computer to show detailed pictures of your blood vessels and your brain
• MRI, which uses a strong magnetic field and radio waves to show detailed pictures of your blood vessels and your brain
• An echocardiogram, which shows how well your heart muscle is pumping

How is it treated?

Treatment of temporary blindness depends on the cause. Aspirin or blood thinners may be prescribed to help prevent blood clots. High cholesterol levels, high blood pressure, and diabetes may be treated with diet and medicine. If you smoke, it is very important to stop. If there is a serious blockage of a blood vessel in your neck, you may need surgery to remove the blockage.

How can I take care of myself?

Follow the full course of treatment your healthcare provider prescribes. Ask your healthcare provider:

• How and when you will hear your test results
• How long it will take to recover
• If there are activities you should avoid and when you can return to your normal activities
• How to take care of yourself at home
• What symptoms or problems you should watch for and what to do if you have them

Make sure you know when you should come back for a checkup. Keep all appointments for provider visits or tests.

How can I help prevent episodic blindness?

Healthy behaviors can help prevent episodic blindness, as well as a stroke or other health problems. Talk to your healthcare provider about what you can do to have a healthy lifestyle, such as:

• Maintain normal blood pressure, blood sugar, and cholesterol levels with diet, exercise, and medicine, if prescribed.
• Eat a healthy diet and keep a healthy weight.
• Stay fit with the right kind of exercise for you.
• Learn to manage stress.
• If you smoke, try to quit. Talk to your healthcare provider about ways to quit smoking.
• If you want to drink alcohol, ask your healthcare provider how much is safe for you to drink.