Part 1: Diabetes and the Eye - Causes and Treatments
- Commentary by Dr. Todd Wilbee

Diabetes is a major health issue in North America. There are approximately 1.4 million people in Canada with diabetes and this number is expected to increase to 3 million by 2010. According to the Ontario Ministry of Health, as many as 200,000 residents in Ontario have the disease and do not even know it.

Why is the incidence of diabetes still increasing at alarming rates? One factor is the improved methods of diagnosis, which makes it easier to identify new diabetics.  Most experts place most of the blame primarily on the apparent epidemic of obesity in our society today. Obesity presents many health risks; developing diabetes being the greatest. 

Diabetes is a disease in which the blood glucose levels are too high. After a meal, food is broken down into a sugar called glucose which is transported by the blood to the cells throughout the body. Insulin is needed to convert the glucose into energy.  With Type1 or early-onset diabetes, there is a lack or absence of insulin in the body to perform this process. Type 2 or late-onset diabetics produce enough insulin; however the body does not properly use it to convert the glucose into energy. Prolonged increased blood glucose levels can lead to nerve and blood vessel damage, which ultimately can result in stroke, heart disease, blindness, extremity amputation and even death.

The most damaging eye condition caused by diabetes is diabetic retinopathy. The incidence of this disease increases the longer someone has diabetes.  Diabetic retinopathy causes the blood vessels of the retina (inner layer of the back of the eye) to leak, swell or develop abnormally which causes damage to the retina. This can result in vision loss that can range from mild to severe.

Laser surgery can be used by an ophthalmologist to minimize the damage caused by diabetic retinopathy. However, laser surgery must be done in a timely fashion to be effective and it does not always return vision back to normal levels. The lasers used to treat diabetic retinopathy are much different than the lasers used for refractive eye surgery.  Another surgical option for patients suffering from persistent diabetic retinopathy involves the surgeon injecting the eyeball with a steroid to stabilize the damaging effects of the retinopathy. There are now new medications that can be injected in the eyeball that can prevent the growth of the abnormal blood vessels seen in diabetic retinopathy.

Very often people with diabetes do not know that they have diabetic retinopathy until significant damage is done to the retina. Prevention of diabetic retinopathy is best accomplished by maintaining normal blood glucose levels, blood pressure and blood lipid levels. A regular eye exam (minimum once a year) by an optometrist or ophthalmologist is essential to catch retinal changes as early as possible. 

Part 2: Diabetes and the Eye - Diagnosis and Control
- Commentary by Dr. Bill Ulakovic

Can diabetes be harmful to your vision? OAO's Dr. Bill Ulakovic explains that it diabetes can bring about an adverse impact to your eyesight and vision health.

In the decade between 1995 and 2005, the overall prevalence of diabetes in Ontario increased by 69 per cent, a rate that continues to increase each year.

• Diagnosis and treatment - Good control of diabetes is the best way of preventing ocular complications.Having your eyes checked regularly by an optometrist is the most effective way of detecting any damage to your eyes. This should be at least every year if you are taking insulin, and every 2 years if you are not. However, if you are getting symptoms like blurred vision, especially if this comes on suddenly, then see a doctor without delay

• Treatment of retinal disease - If damage to the retina has already occurred, laser treatment (in which a laser beam is directed at the retina to repair damaged blood vessels) is very effective in preventing vision loss. Laser surgery works best if it isn’t done too early or too late— another reason why it is vital to obtain regular eye examinations.

• Cataract surgery - Cataract surgery performed on diabetics usually has excellent results.  However, if there is any significant diabetic retinopathy present the ophthalmologist will often treat the retinopathy first and ensure that this condition is stable prior to proceeding with surgery.

• Additional risk factors - High blood pressure and elevated cholesterol levels need to be controlled as they can increase the damage to the eye in people with diabetes. If you are pregnant, good control of diabetes is vital for both you and your baby.

• Smoking - If you smoke, you should definitely stop. Nicotine constricts blood vessels, which can be harmful to a person with diabetes. In addition, smoking increases the risk of developing macular degeneration. Talk to your doctor about giving up now. There are many methods available to help you, “kick the habit.”