What is diabetic retinopathy?
Diabetic retinopathy is an eye condition that affects the retinas of people with diabetes. It is caused by changes in the blood vessels of the eye and occurs as a result of high blood sugar (glucose) that people with diabetes have over a long period of time.
The retina is a light-sensitive nerve tissue at the back of the eye. The retina converts the light rays that enter the eye into electrical impulses that travel along the optic nerve to the brain. Too much blood glucose can destroy the blood vessels in the back of the eye, preventing the retina from receiving the proper amount of nutrients it needs to maintain vision.
Diabetic retinopathy occurs when diabetes damages the tiny blood vessels in the retina. In the early stages of the disease (nonproliferative retinopathy), these blood vessels leak fluid and distort sight. In the more advanced stage (proliferative retinopathy), fragile new blood vessels grow around the retina and in the vitreous humor (a clear substance inside the eye). If these blood vessels are not treated, they may bleed and blur vision, or may scar and detach (disconnect) the retina.
Anyone with diabetes (Type 1 or Type 2) is at risk of developing diabetic retinopathy. The factors that affect risk include:
- The type of diabetes a person has (Type 1 or 2);
- How well-controlled the blood glucose is; and,
- How long a person has had diabetes.
What are the symptoms of diabetic retinopathy?
Usually, there are no symptoms of early diabetic retinopathy, and the person’s sight may not be affected until the condition is severe.
Symptoms of diabetic retinopathy include:
- The loss of central vision, for example, when reading or driving;
- Loss of the ability to see color;
- Blurred or distorted vision;
- Small spots (floaters).
Because retinopathy develops over time, it is important to have an eye exam each year, or more often if you have more than mild retinopathy. Call your doctor right away if you have any of these symptoms.