Overview
Diabetic retinopathy is a complication of diabetes that affects the eyes. It is caused by damage to the blood vessels in the light-sensitive tissue at the back of the eye, called the retina.
Diabetic retinopathy (die-uh-BET-ik ret-ih-NOP-uh-thee) can develop in anyone who has type 1 or type 2 diabetes. The risk increases the longer someone has diabetes and if blood sugars are not managed well.
At first, diabetic retinopathy might cause no symptoms or only mild vision problems. But it can lead to blindness, especially if diabetes or other health problems are poorly managed.
Symptoms
Some people have no symptoms in the early stages of diabetic retinopathy. As the condition gets worse, people may develop:
- Spots or dark strings floating in their sight, called floaters.
- Blurred vision.
- Changes in vision.
- Dark or empty areas in their vision.
- Vision loss.
When to see an eye doctor
Proper treatment of diabetes is the best way to prevent vision loss. If you have diabetes, a yearly dilated eye exam with an eye care professional is recommended, even if your vision seems fine.
Developing diabetes when pregnant, called gestational diabetes, or having diabetes before becoming pregnant can increase your risk of diabetic retinopathy. If you're pregnant, your healthcare professional might recommend additional eye exams throughout your pregnancy.
Contact a medical professional right away if your vision changes suddenly or becomes blurry, spotty or hazy.
Causes
Over time, too much sugar in your blood causes damage to the tiny blood vessels that nourish the retina, cutting off its blood supply. In advanced stages of diabetic retinopathy, the eye tries to grow new blood vessels. These new blood vessels don't develop correctly and can leak or bleed easily.
There are two types of diabetic retinopathy:
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Nonproliferative diabetic retinopathy. In this more common form of the condition, also called NPDR, new blood vessels aren't growing.
When you have NPDR, the walls of the blood vessels in the retina weaken. Tiny bulges stick out from the walls of the smaller vessels, sometimes leaking fluid and blood into the retina. Larger retinal vessels can begin to swell and become irregular in width. The condition can progress from mild to severe as more blood vessels become damaged.
Sometimes, retinal blood vessel damage leads to a buildup of fluid, called edema. This happens in the center portion of the retina, called the macula. If macular edema affects vision, treatment may be needed to reduce swelling and prevent lasting vision loss. Macular edema can happen in both nonproliferative and proliferative diabetic retinopathy.
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Proliferative diabetic retinopathy. Diabetic retinopathy can get worse in this more severe type, also called PDR. Damaged blood vessels close off, causing the growth of new, irregular blood vessels in the retina. These new blood vessels can leak into the clear, jellylike matter that fills the center of your eye, called the vitreous.
In time, scar tissue from the growth of new blood vessels can cause the retina to detach from the back of your eye. If the new blood vessels block the flow of fluid out of the eye, pressure can build in the eyeball. This buildup can hurt the optic nerve, which carries information from your eye to your brain, resulting in glaucoma.
Diabetic retinopathy
In the early stages of diabetic retinopathy, the walls of the blood vessels in your retina weaken. Tiny bulges stick out from the vessel walls, sometimes leaking or oozing fluid and blood into the retina. Cells in the retina may swell, producing white spots in the retina. As diabetic retinopathy worsens, new blood vessels may grow and damage your vision.
Risk factors
Anyone who has diabetes can develop diabetic retinopathy. However, the risk may increase as a result of:
- Having diabetes for a long time.
- Poorly managed blood sugar levels.
- High blood pressure.
- High cholesterol.
- Pregnancy.
- Tobacco use.
- Being Black, Latino or Native American.
Complications
Diabetic retinopathy happens when blood vessels in the retina become damaged. Irregular blood vessel growth in proliferative diabetic retinopathy can lead to serious vision problems:
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Vitreous hemorrhage. These new blood vessels are weak and can leak into the clear, jellylike matter that fills the center of your eye, called the vitreous. If the amount of bleeding is small, you might see only a few dark spots, called floaters. In more-severe cases, blood can fill the vitreous cavity and completely block your vision.
Vitreous hemorrhage by itself usually doesn't cause permanent vision loss, but the retina will need treatment focused on the underlying cause of the vitreous hemorrhage. The blood often clears from the eye within a few weeks or months. Unless your retina is damaged, your vision will likely return to its earlier clarity.
- Retinal detachment. The irregular blood vessels that develop with diabetic retinopathy trigger the growth of scar tissue. This can cause the retina to pull away from the back of the eye. This can cause spots floating in your vision, flashes of light, missing areas of vision or severe vision loss.
- Glaucoma. New blood vessels can grow in the colored front part of the eye, called the iris. These new blood vessels block the usual flow of fluid out of the eye. This can cause pressure to build up in the eye, leading to a condition called glaucoma. This pressure can damage the optic nerve, which carries images from your eye to your brain.
- Blindness. Diabetic retinopathy, macular edema, glaucoma or a combination of these conditions can lead to complete vision loss, especially if health problems are poorly managed.
Prevention
You can't always prevent diabetic retinopathy. However, regular eye exams, good management of your blood sugar and blood pressure, and early treatment of vision problems can help stop vision loss.
If you have diabetes, reduce your risk of getting diabetic retinopathy by doing the following:
- Manage your diabetes. Make healthy eating and physical activity part of your daily routine. Try to get at least 150 minutes of moderate aerobic activity, such as walking, each week. Take diabetes medicines or insulin as directed.
- Monitor your blood sugar level. You might need to check and record your blood sugar level several times a day or more often if you're ill or under stress. Ask a healthcare professional how often you need to test your blood sugar.
- Ask about a glycosylated hemoglobin test. The glycosylated hemoglobin test is also called the hemoglobin A1C test. It shows your average blood sugar level for the 2- to 3-month period before the test. Ask the health professional managing your diabetes what your A1C goal should be.
- Manage your blood pressure and cholesterol levels. Eating healthy foods, exercising regularly and losing excess weight can help. Sometimes medicine is needed too.
- If you smoke or use other types of tobacco, stop. Ask a healthcare professional to help you quit. Smoking increases the risk of many diabetic complications, including diabetic retinopathy.
- Pay attention to vision changes. Contact a medical professional right away if your vision suddenly changes, becomes blurry, spotty or hazy.
Remember, diabetes doesn't always lead to vision loss. Managing your diabetes well can help stop problems.
