Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. It is caused by changes in the blood vessels of the retina, the light-sensitive tissue at the back of the eye necessary for good vision.
In some people with diabetic retinopathy, retinal blood vessels may leak fluid and cause swelling of the retina in the macular region, which adversely affects central vision. In other people, abnormal new blood vessels grow on the surface of the retina and can cause severe bleeding into the eye.
If you have diabetic retinopathy, at first you may not notice changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss. Diabetic retinopathy usually affects both eyes.
Often there are no symptoms in the early stages of the disease, nor is there any pain. Don't wait for symptoms. Be sure to have a comprehensive dilated eye exam at least once a year.
Blurred vision may occur when the macula – the part of the retina that provides sharp central vision – swells from leaking fluid. This condition is called macular edema. If new blood vessels grow on the surface of the retina, they can bleed into the eye and block vision.
At first, you will see a few specks of blood, or spots, "floating" in your vision. If spots occur, see your eye care professional as soon as possible.
You may need treatment before more serious bleeding occurs. Hemorrhages tend to happen more than once, often during sleep. If left untreated, proliferative retinopathy can cause severe vision loss and even blindness. The earlier you receive treatment, the more effective it will be.
The Stages of Diabetic Retinopathy
Diabetic retinopathy has 4 stages:
At the initial stage, micro-aneurysms occur. They are small areas of balloon-like swelling in the retina's tiny blood vessels.
As the disease progresses, some blood vessels that nourish the retina are blocked.
Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment.
At this advanced stage, the signals sent by the retina for nourishment trigger the growth of new blood vessels. This condition is called proliferative retinopathy. These new blood vessels are abnormal and fragile. They grow along the retina and along the back surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result.
During the first three stages of diabetic retinopathy, no treatment is needed, unless you have macular edema. To prevent progression of diabetic retinopathy, people with diabetes should control their levels of blood sugar, blood pressure and blood cholesterol.
Proliferative diabetic retinopathy is treated with laser surgery. At the Irwin Retina Center, laser surgery is done as an outpatient procedure and requires no surgical incision. A strong light beam is aimed onto the retina to treat and shrink the abnormal vessels. If the bleeding is severe, you may need a surgical procedure called a vitrectomy. During a vitrectomy, blood is removed from the center of the eye.
If you have macular edema, laser surgery may also be used. In this case, the laser beam is used to seal the leaking blood vessels. If you have macular edema in both eyes and require laser surgery, generally only one eye will be treated at a time, usually several weeks apart. Focal laser treatment stabilizes vision. Laser treatment reduces the risk of vision loss by 50 percent. In a small number of cases, if vision is lost, it can be improved.
Finding diabetic retinopathy early is the best way to prevent vision loss. With timely treatment, the majority of those with advanced diabetic retinopathy can be saved from going blind.