With diabetes, the body can’t use or store sugar properly. Diabetes damages the blood vessels in the eye, eventually causing diabetic retinopathy. In later stages, the disease may lead to new blood vessel growth over the retina. These new blood vessels cause scar tissue to develop, which can pull the retina away from the back of the eye. This is known as retinal detachment, and it can lead to blindness if untreated. The presence and severity of diabetic retinopathy is related to the duration of one’s diabetes. However, severe and significant diabetic retinopathy can be present at the time of diagnosis especially with adult onset diabetes.
Everyone who has diabetes is at risk for developing diabetic retinopathy. In the early or advanced stages of diabetes, symptoms may be absent or minimal. Therefore, regular diabetic screening evaluations are recommended. The symptoms of diabetic retinopathy can include floaters, blurred vision or double vision. Sometimes difficulty reading or doing close work can indicate that fluid is collecting in the macula, the most light-sensitive part of the retina. This process of fluid buildup is called macular edema.
Over time, diabetes affects the circulatory system of the retina. The earliest phase of the disease is known as background diabetic retinopathy. In this phase, the arteries in the retina become weakened and leak, forming small, dot-like hemorrhages. These leaking vessels often lead to swelling (or edema) in the retina and decreased vision.
The severity of diabetic retinopathy can be limited or prevented by close monitoring and control of blood sugars, blood pressures and blood lipids, such as cholesterol. Control of any one of these risk factors can reduce the severity of diabetic retinopathy. According to the American Academy of Ophthalmology, 95% of those with significant diabetic retinopathy can avoid substantial vision loss if they are treated in time. The possibility of early detection is why it is so important for diabetics to have a dilated eye exam at least once a year.
Diabetic retinopathy can be treated with laser photocoagulation to seal off leaking blood vessels and destroy new growth. Laser photocoagulation doesn’t cause pain, because the retina does not contain nerve endings. In some patients, blood leaks into the vitreous humor and clouds vision. A procedure called a vitrectomy removes blood that has leaked into the vitreous humor. The body gradually replaces lost vitreous humor, and vision usually improves.
