Do you have a dilated eye exam once per year? If you have diabetes, you should! That is the only way you can detect and prevent the number one cause of blindness in the United States. Retinopathy is the most common eye disease in diabetes. A dilated eye exam is the earliest way to detect it. Symptoms will not tell you. Usually there are no symptoms until the disease has progressed beyond where it should without treatment. A vision check will not tell you either. Without actually dilating the eye, retinopathy will not likely be noticed. Changes in vision do not happen early in the disease.

Retinopathy is caused by changes in the blood vessels of the retina. Much like the arteries around the heart clog when heart disease is present, the small blood vessels in the eye clog when eye disease is present. In some people with retinopathy, clogged blood vessels may swell and leak fluid. This is called macular degeneration. In other people, abnormal new blood vessels grow on the surface of the retina to bypass the clogged ones. When these new blood vessels form, it is called proliferative retinopathy. Both proliferative retinopathy and macular edema can damage vision.

The longer someone has diabetes, the more likely he or she will get diabetic retinopathy. Between 40 to 45 percent of Americans diagnosed with diabetes have some stage of diabetic retinopathy. If you have diabetic retinopathy, your doctor can recommend treatment to help prevent its progression. During pregnancy, diabetic retinopathy may be a problem. Your doctor may recommend additional exams during pregnancy.

If you have diabetic retinopathy, you may need an eye exam more often. People with proliferative retinopathy can reduce their risk of blindness by 95 percent with timely laser treatment and follow-up care. Most importantly, better control of blood sugar levels slows the onset and progression of retinopathy. Better control also reduces the need for sight saving laser surgery. Studies have also shown that controlling elevated blood pressure and cholesterol can reduce the risk of vision loss.

When you have a dilated eye exam to check for the disease, your eye care professional checks your retina for signs of the disease including retinal swelling (macular edema), pale, fatty deposits on the retina--signs of leaking blood vessels, damaged nerve tissue, and any changes to the blood vessels (proliferative retinopathy).

• Proliferative retinopathy can develop without symptoms. At this advanced stage, you are at high risk for vision loss.

• Macular edema can develop without symptoms at any of the four stages of diabetic retinopathy.

• You can develop both proliferative retinopathy and macular edema and still see fine. However, you are at high risk for vision loss.

• Your eye care professional can tell if you have macular edema or any stage of diabetic retinopathy. Whether or not you have symptoms, early detection and timely treatment can prevent vision loss.

Treatment

Initially no eye treatment is needed for retinopathy unless you have macular edema. To prevent progression of the retinopathy, you should control your levels of blood sugar, blood pressure, and blood cholesterol. Proliferative retinopathy, or abnormal new blood vessels, may develop later in the stages of the disease. This is treated with laser surgery. Laser treatment helps shrink the new blood vessels. Two or more sessions usually are required to complete this type of treatment. Although you may notice some loss of your side vision, laser treatment can save the rest of your sight. Laser treatment may also slightly reduce your color vision and night vision.

Laser treatment is performed in your doctor's office or eye clinic. Before the surgery, your doctor will dilate your pupil and apply drops to numb the eye. The area behind your eye also may be numbed to prevent discomfort.

The lights in the office will be dim. As you sit facing the laser machine, your doctor will hold a special lens to your eye. During the procedure, you may see flashes of light. These flashes eventually may create a stinging sensation that can be uncomfortable. You will need someone to drive you home after surgery. Because your pupil will remain dilated for a few hours, you should bring a pair of sunglasses.

For the rest of the day, your vision will probably be a little blurry. If your eye hurts, your doctor can suggest treatment. Laser surgery and appropriate follow-up care can reduce the risk of blindness by 90 percent. However, laser surgery often cannot restore vision that has already been lost. That is why finding diabetic retinopathy early is the best way to prevent vision loss.

If there is too much bleeding in the center of the eye (vitreous gel) from the disease, you may need a surgical procedure called a vitrectomy. During a vitrectomy, blood is removed from the center of your eye. Your doctor makes a tiny incision in your eye. Next, a small instrument is used to remove the vitreous gel that is clouded with blood. The vitreous gel is replaced with a salt solution. Because the vitreous gel is mostly water, you will notice no change between the salt solution and the original vitreous gel. You will probably be able to return home after the vitrectomy. Some people stay in the hospital overnight. Your eye will be red and sensitive. You will need to wear an eye patch for a few days or weeks to protect your eye. You also will need to use medicated eye drops to protect against infection.

People with proliferative retinopathy have less than a five percent chance of becoming blind within five years when they get timely and appropriate treatment. Although treatments have high success rates, they do not cure diabetic retinopathy. Once you have proliferative retinopathy, you always will be at risk for new bleeding. You may need treatment more than once to protect your sight.

Michelle Herbert, PharmD, Certified Diabetes Educator