One of the more serious effects of uncontrolled diabetes is microvascular disease. Diabetic retinopathy is caused by damage of the tiny blood vessels that supply nutrients to the retina. Microvascular changes that cause damage to the retina often occurs about seven years after the onset of diabetes. In the early or “non-proliferative” stages of retinopathy, these blood vessels weaken and bulge and may leak blood or fluid into the surrounding tissue. While careful eye examination can detect mild retinal changes, the damage that threatens vision does not occur until much later.
Proliferative retinopathy, a later stage of the disease, is characterized by growth of new blood vessels on the retina. These blood vessels may rupture and release blood into the vitreous, causing blurred vision or temporary blindness or they can distort the retina and lead to retinal detachment producing vision loss that is often irreversible.
According to the American Diabetes Association, nearly all type 1 diabetes patients develop retinopathy and more than 60% of patients with type 2 diabetes will develop some degree of retinopathy.
Diligent control over diabetes by maintaining low blood glucose levels is important in reducing the risk of developing retinopathy. The American Diabetes Association has suggested guidelines for regular eye examinations. Patients under 10 years of age, with type 1 diabetes, should have an initial comprehensive and dilated eye exam within 3 to 5 years of diagnosis. Patients with type 2 diabetes should have a comprehensive and dilated eye exam shortly after diagnosis is made. After that, eye exams should be conducted annually by an ophthalmologist who is experienced in diagnosing and treating diabetic retinopathy.
Diabetic retinopathy can be treated with laser photocoagulation if it is detected early.