Diabetic retinopathy

Definition

Diabetic retinopathy is progressive damage to the eye's retina caused by long-term diabetes. It can cause blindness.

Alternative Names

Retinopathy - diabetic

Causes

Diabetic retinopathy is caused by damage to blood vessels of the retina, the light-sensitive outer layer of the eye.

It is classified as non-proliferative or proliferative.

• Non-proliferative diabetic retinopathy is the early stage of the disease and is less severe. The existing blood vessels in the eye start to leak fluid into the retina, which leads to blurred vision.
• Proliferative retinopathy is the more advanced form of the disease, and more severe. New blood vessels start to grown within the eye. These new vessels are fragile and can bleed (hemorrhage), which may cause vision loss and retinal scarring.

Diabetic retinopathy is the leading cause of blindness in working-age Americans. People with both type 1 diabetes and type 2 diabetes are at risk for this condition.

The likelihood and severity of retinopathy increase the longer you have diabetes, and is likely to occur earlier and be more severe if your diabetes is poorly controlled. Almost everyone who has had diabetes for more than 30 years will show signs of diabetic retinopathy.

Symptoms

One of the first symptoms of diabetic retinopathy is poor night vision. Other symptoms include:

• "Floaters" (spots in front of one's eyes)
• Blurred vision
• Blindness

However, many people have no symptoms before major bleeding occurs in the eye. This is why everyone with diabetes should have regular eye exams.

Exams and Tests

Treatment

The goal of treatment is to control your blood sugar, blood pressure, and cholesterol. 

Treatment, however, usually does not reverse existing damage, but will keep the disease from getting worse.  Drugs that keep abnormal blood vessels from growing in patients with proliferative diabetic retinopathy are under development.

Laser surgery may be used to keep vessels from leaking or to get rid of abnormal fragile vessels.

A surgical procedure called vitrectomy is used when there is bleeding (hemorrhage) into the eye. It may also be used to repair retinal detachment.

Support Groups

American Diabetes Association - www.diabetes.org

National Diabetes Information Clearinghouse - www.diabetes.niddk.nih.gov

Prevent Blindness America - www.preventblindness.org

Outlook (Prognosis)

Patients who have good control of their blood sugar and blood pressure may improve their outcomes.

Diabetic retinopathy can lead to blindness without treatment.

Possible Complications

• Glaucoma
• Retinal detachment
• Blindness

When to Contact a Medical Professional

Call for an appointment with an ophthalmologist (eye doctor) if you have diabetes

Prevention

People with diabetes should see an ophthalmologist to have their eyes dilated once a year. This lets the doctor see the retina. Frequent eye exams and laser surgery, if necessary, can prevent blindness in most cases.

Sydorova M, Lee MS. Vascular Endothelial Growth Factor Levels in Vitreous and Serum of Patients with either Proliferative Diabetic Retinopathy or Proliferative Vitreoretinopathy. Ophthalmic Res. 2005 Jun 29;37(4):188-190.

Singerman L. Findings of the Phase 2 Trial of the Safety and Efficacy of Pegaptanib Sodium (Macugen™) in Patients With Diabetic Macular Edema.  Invest Ophthalmol Vis Sci 2005;46: E-Abstract 4674.

Rosenblatt RJ, Benson WJ. Diabetic Retinopathy. In: Yanoff M, ed. Opthalmology. 2nd ed. St. Louis, MO: Mosby; 2004;877-887.