Ailment Known to Diminish Vision

Posted on Wed, Apr. 18, 2007

By Dr. Steven Harrison

A YOUNG WOMAN (we'll call her Nancy) became concerned about her loss of vision and was referred to our ophthalmology clinic.

An examination of her eyes revealed that her uncontrolled diabetes was the cause of her partial blindness. Nancy hadn't realized she was risking diabetic retinopathy, a diabetes-related condition that is the leading cause of blindness in American adults.

What is diabetic retinopathy?

Diabetic retinopathy (re-tin-AW-path-ee) means diabetes has caused damage to the blood vessels in the retina, the light-sensitive area at the back of the eye.

Diabetes can damage small blood vessels throughout the body, including the brain, heart, kidneys, feet and the eye.

In diabetic retinopathy, the walls of the blood vessels become weak, so they swell and break and leak fluid and blood into the retina and eyeball.

There are two major types of diabetic retinopathy: In proliferative retinopathy, the condition is more advanced with many blood vessels damaged so there is insufficient oxygen for the retina.

The retina senses that it has too little oxygen and stimulates the growth of more blood vessels in an attempt to acquire more oxygen. But the new vessels don't form properly and can leak blood, which causes cloudy vision and scar tissue.

Nonproliferative retinopathy is less advanced with fewer vessels affected.

Who is at risk?

Diabetics -- both type 1 (youth onset) and type 2 (adult onset)
Pregnant women with diabetes

The longer someone has diabetes, the more likely he or she will get diabetic retinopathy. About 40 percent of American diabetics have some stage of diabetic retinopathy.

What are the symptoms?

Usually there is no pain or other symptoms in the early stages of diabetic retinopathy. But over time, it can get worse and cause vision loss. The symptoms generally affect both eyes, causing blurred vision and specks of blood or spots "floating" in your vision.

Prevention

The key to prevention is to control the blood sugar and to get a comprehensive dilated eye exam by an ophthalmologist every year.

Don't confuse an ophthalmologist, who diagnoses and treats eye diseases, with an optometrist, who helps vision with corrective lenses. Only an ophthalmologist can treat diabetic retinopathy.

Pregnant women with diabetes and those who have been diagnosed with diabetic retinopathy will need more frequent eye exams.

How is diabetic retinopathy detected?

An eye doctor will examine the retina for signs of the disease and may perform photographic testing to determine the extent of the damage.

Treatment

Laser surgery can effectively stop or slow the progression of the disease by cauterizing or shrinking the abnormal blood vessels. Steroid or other drug injections also can help decrease vessel leakage.

If bleeding into the eye is severe, a surgical procedure called a vitrectomy may be needed to remove the blood from the center of the eye.

If you or someone you love has diabetes, work with your doctor to control your blood sugar, and be sure to get an examination by an eye specialist. Don't be like Nancy and wait until vision loss has occurred.

In diabetic retinopathy, early detection is important to avoid blindness.

Harrison is an ophthalmologist/retina specialist at Contra Costa Regional Medical Center.