Diabetic retinopathy is caused by damage to blood vessels of the retina. The retina is the layer of tissue at the back of the inner eye. It changes light and images that enter the eye into nerve signals that are sent to the brain.
Diabetic retinopathy is the leading cause of blindness in working-age Americans. Having more severe diabetes for a longer period of time increases the chance of getting retinopathy. Retinopathy is also more likely to occur earlier and be more severe if your diabetes has been poorly controlled.
Almost everyone who has had diabetes for more than 30 years will show signs of diabetic retinopathy.
Most often, diabetic retinopathy has no symptoms until the damage to your eyes is severe.
Symptoms of diabetic retinopathy include: blurred vision and slow vision loss over time, floaters, shadows or missing areas of vision, and trouble seeing at night.
Many people with early diabetic retinopathy have no symptoms before major bleeding occurs in the eye. This is why everyone with diabetes should have regular eye exams.
Signs and Tests
Your doctor can diagnose diabetic retinopathy by dilating your pupils with eye drops and then carefully examining the retina.
If you have nonproliferative diabetic retinopathy, your health care provider may see: blood vessels in the eye that are larger in certain spots (called microaneurysms), blood vessels that are blocked, small amounts of bleeding (retinal hemorrhages), and fluid leaking into the retina.
If you have proliferative retinopathy, your health care provider may see: new blood vessels starting to grow in the eye that are fragile and can bleed, and scars developing on the retina and in other parts of the eye (the vitreous).
To prevent diabetic retinopathy, keep tight control of your blood sugar (glucose), blood pressure, and cholesterol level. And, do not smoke.
People with the earlier form (nonproliferative) of diabetic retinopathy may not need treatment. However, they should be closely followed by an eye doctor who is trained to treat diabetic retinopathy.
Treatment usually does not reverse damage that has already occurred. However, it can help keep the disease from getting worse. Once your eye doctor notices new blood vessels growing in your retina (neovascularization) or you develop macular edema, treatment is usually needed.
Several procedures or surgeries are the main treatment for diabetic retinopathy.
Laser eye surgery creates small burns in the retina where there are abnormal blood vessels. This process is called photocoagulation. It is used to keep vessels from leaking or to get rid of abnormal, fragile vessels.
Drugs that reduce swelling in the retina, and drugs that prevent abnormal blood vessels from growing, can be injected into the eyeball, as new treatments for diabetic retinopathy.