Diabetic Retinopathy

by National Institute on Aging

What is Diabetic Retinopathy?

Diabetic retinopathy is a complication of diabetes and a leading cause of blindness. It occurs when diabetes damages the tiny blood vessels inside the retina in the back of the eye. A healthy retina is necessary for good vision.

What is Diabetic Eye Disease?If you have diabetic retinopathy, at first you may notice no changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss. Diabetic retinopathy usually affects both eyes.

The four stages of diabetic retinopathy are

• mild nonproliferative retinopathy
• moderate nonproliferative retinopathy
• severe nonproliferative retinopathy
• proliferative retinopathy.

The first stage is mild nonproliferative retinopathy. At this earliest stage, there are small areas of balloon-like swelling in the retina's tiny blood vessels.

The second stage is moderate nonproliferative retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked.

The third stage is severe nonproliferative retinopathy. Many more blood vessels are blocked, depriving several areas of the retina of their blood supply. These areas send signals to the body to grow new blood vessels for nourishment.

The fourth stage is proliferative retinopathy. At this advanced stage, the signals sent by the retina for nourishment cause the growth of new blood vessels. These new blood vessels are abnormal and fragile.

The new blood vessels grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result.

Quiz

1. Diabetic retinopathy is a complication of diabetes and a leading cause of blindness.

TRUE is the correct answer. Diabetic retinopathy occurs when diabetes damages the tiny blood vessels inside the retina, the tissue at the back of the eye.

2. If you have diabetic retinopathy, at first you may notice many changes to your vision.

FALSE is the correct answer. If you have diabetic retinopathy, at first you may notice no changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss.

3. There are two stages of diabetic retinopathy.

FALSE is the correct answer. Diabetic retinopathy has four stages. They are mild nonproliferative retinopathy, moderate nonproliferative retinopathy, severe nonproliferative retinopathy, and proliferative retinopathy.

4. If diabetic retinopathy progresses to its advanced stage, blindness can occur.

TRUE is the correct answer. At the proliferative retinopathy stage, abnormal and fragile blood vessels develop. These vessels may leak and cause severe vision loss and even blindness.

Causes and Risk Factors

All people with diabetes - both type 1 and type 2 - are at risk for diabetic retinopathy. That's why everyone with diabetes should get a comprehensive dilated eye exam at least once a year.

Between 40 to 45 percent of Americans diagnosed with diabetes have some stage of diabetic retinopathy. If you have diabetic retinopathy, your doctor can recommend treatment to help prevent its progression.

Blood vessels damaged from diabetic retinopathy can cause vision loss in two ways.

Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the fourth and most advanced stage of the disease.

Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema.

Macular edema can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses. About half of the people with proliferative retinopathy also have macular edema.

Quiz

1. All people with diabetes - both type 1 and type 2 - are at risk for diabetic retinopathy.

TRUE is the correct answer. All people with diabetes - both type 1 and type 2 - are at risk for diabetic retinopathy. That's why everyone with diabetes should get a comprehensive dilated eye exam at least once a year.

2. The iris is the part of the eye where sharp, straight-ahead vision occurs.

FALSE is the correct answer. The center of the macula is the part of the eye where sharp, straight-ahead vision occurs.

3. A condition called macular edema can result in blurry vision.

TRUE is the correct answer. Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema.

4. About half of the people with proliferative retinopathy also have macular edema.

TRUE is the correct answer. About half of the people with proliferative retinopathy also have macular edema. It can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses.

About the Author

www.nia.nih.gov
NIA, one of the 27 Institutes and Centers of NIH, leads a broad scientific effort to understand the nature of aging and to extend the healthy, active years of life. In 1974, Congress granted authority to form NIA to provide leadership in aging research, training, health information dissemination, and other programs relevant to aging and older people.