People with diabetes are not able to use or store sugar correctly. As a result, sugar can build up in the blood and cause damage throughout the body, including the eyes. Diabetic retinopathy is the most common diabetic eye disease and is the leading cause of blindness in adults in the United States.
What is Diabetic Retinopathy?
The light-sensitive lining inside the back of the eye is called the retina. This is the part of the eye that changes images into nerve signals that are sent to the brain. Tiny blood vessels carry oxygen and nutrients to the retina to keep it healthy and to promote good vision. In people with diabetes, excess sugar in the blood can damage these blood vessels and stop the retina from getting the nutrients it needs. This condition is known as diabetic retinopathy.
The longer a person has diabetes -- either type 1 or type 2–the better the chances this kind of eye damage will occur. There are two types of diabetic retinopathy:
Non-proliferative diabetic retinopathy (NPDR):
This is the first stage of the disease. Blood vessels in the eyes become larger in some places, called microaneurysms. Blood vessels may also become blocked, and small amounts of blood and other fluids may leak into the retina. Eventually, this fluid in the retina can lead to noticeable vision problems.
Proliferative diabetic retinopathy (PDR):
This is the more advanced form of the disease. As blood vessels in the eye are blocked, the retina does not receive enough oxygen. This causes fragile new blood vessels to grow in the retina and the vitreous, which is the gel-like fluid inside the eye. Because these vessels are so fragile, they can leak blood into the vitreous, which clouds the vision. Other possible complications from PDR include a detached retina and glaucoma which causes damage to the optic nerve.
Risk factors for Diabetic Retinopathy
Everyone who has diabetes, either type 1 or type 2, is at risk for diabetic retinopathy. Approximately 40 percent of Americans who have diabetes have some degree of diabetic retinopathy.