What is Diabetic Retinopathy?
Over time, diabetes can damage small blood vessels throughout the body. This blood vessel damage can cause foot ulcers, nerve numbness and kidney failure. In the eye, it can cause retinal damage, known as diabetic retinal disease, or diabetic retinopathy.
Causes of Diabetic Retinopathy
People lose vision from diabetic retinopathy due to two major causes: swelling and bleeding. Swelling of the retina can occur when blood vessels leak fluid. When fluid leakage causes swelling in the central retina, or macula, vision becomes blurred. If diabetic retinopathy is severe, the retina becomes starved for oxygen. Blood vessels may then grow out of the retina or optic nerve into the vitreous jelly that fills the inside of the eye. These fragile vessels can cause bleeding into the eye and block light from reaching the retina. Without adequate light, vision is impaired. Bleeding can result in severe scarring, leading to retinal detachment.
Anyone with diabetes is at risk for diabetic retinopathy. The risk of developing diabetic retinopathy is related to the length of time one has diabetes and the severity of the disease. However, even people with newly diagnosed diabetes can have retinal disease that needs treatment. In addition, diabetic retinopathy can develop in people with excellent blood sugar control, even if the diabetes is mild and can be managed by proper diet. Women who have diabetes during pregnancy should be examined for diabetic retinopathy each trimester. Pregnancy sometimes can worsen diabetic eye disease.
Symptoms of Diabetic Retinopathy
Unfortunately, diabetic retinopathy typically has no symptoms in its earliest, treatable stages. By the time people notice a problem with their vision, retinal disease may be advanced and difficult to treat. This is why periodic screening examinations by your ophthalmologist are very important. Diabetic patients should have such examinations even if their vision is completely normal.
When macular swelling (edema) develops, central vision becomes blurred. Activities like reading and driving become difficult. Changing glasses will not improve the blurriness. When a hemorrhage (bleeding) occurs in the eye, spots or streaks of blood can be seen floating in your vision. If bleeding is more severe, or if it continues, a dense fog will blur vision. Occasionally, the blood will be so thick that a person will be able to see only light and dark. Often, blood will dissolve slowly over a period of weeks or months, and vision may improve. Sometimes, however, blood in the vitreous jelly will not clear without surgery.
Diagnosis of Diabetic Retinopathy
The only way to find out if you have diabetic retinopathy is to have a dilated examination of the retina. An examination to detect diabetic retinopathy will include drops to dilate the pupil. Dr. Rhodes can then look through the pupil with a bright light and a special magnifying lens to see the retina and any early signs of diabetic retinopathy. As people can develop diabetic retinopathy at any time, periodic eye examinations are important.