What Is a Retinal Vein Occlusion?

What is a retinal vein occlusion?

Your retina has veins and other blood vessels that carry blood. When a vein in your retina is blocked (occluded), it is called a retinal vein occlusion. This can be caused by a blood clot. Or it can happen when a larger blood vessel presses down on the vein.

With retinal vein occlusion, the blood vessels may become weaker and start to leak, which causes the macula to swell or thicken. This is called macular edema, and it leads to blurry vision or decreased vision.

With an occlusion, abnormal blood vessels can grow in your iris (colored part of your eye). This growth can cause painful pressure in the eye called neovascular (new blood vessels) glaucoma. New blood vessels may also grow in the retina, which can cause bleeding in the back of the eye and retinal detachment.

There are two types of retinal vein occlusion:

• CRVO (central retinal vein occlusion). This is when your eye’s main vein is blocked.
• BRVO (branch retinal vein occlusion). This is when small blood vessels attached to the eye’s main vein are blocked.

What causes retinal vein occlusion?

It is not known exactly what causes retinal vein occlusion. However, you are more likely to have retinal vein occlusion if you have:

• diabetes
• glaucoma (when high pressure inside the eye damages the optic nerve and causes vision loss)
• high blood pressure
• diseases related to blood vessels (vascular disease) or are obese

What are symptoms of retinal vein occlusion?

Symptoms can include:

• blurry or less vision
• noticing a lot of floaters in your field of vision
• pain inside your eye if new blood vessels grow and cause high pressure in your eye

It is very important to call an ophthalmologist right away if you have any symptoms. They will check your eyes thoroughly and talk about treatment options. You may become blind or have permanently reduced vision if you do not have treatment for retinal vein occlusion.

How is retinal vein occlusion diagnosed?

Your ophthalmologist will put drops in your eye to dilate (widen) your pupil. This allows them to look through a special lens at the inside of your eye.

Your doctor may do fluorescein angiography to see what is happening with your retina. Yellow dye (called fluorescein) is injected into a vein, usually in your arm. The dye travels through your blood vessels. A special camera takes photos of the retina as the dye travels throughout its blood vessels. This shows if any blood vessels are blocked or leaking fluid.

Optical coherence tomography (OCT) is another way to look closely at the retina. A machine scans the retina and provides very detailed images of its thickness. This helps your doctor find and measure swelling of your macula.

Optical coherence tomography angiography (OCTA) is another way to look at the blood vessels in the retina without injecting a dye. This helps find blocked blood vessels and abnormal blood vessels.

How is retinal vein occlusion treated?

Your ophthalmologist will treat you based on what they see in your eye. Treatment may include:

• Medicine. A drug is given by injections (shots) inside the eye. It helps to reduce swelling of the macula. This helps to slow vision loss and perhaps improve vision.
• Laser surgery. Your ophthalmologist may use a laser to shrink certain blood vessels in your retina. This is so that they won’t bleed, and to prevent them from growing back. Laser surgery may help slow vision loss and perhaps improve vision.
• Managing your health. Diabetes, glaucoma, high blood pressure or other health problems can lead to retinal vein occlusion. Taking care of your health can keep you from getting this serious eye problem. Your doctor may talk with you about the best ways to manage your health.