Eye Disease

Annual Eye Examinations

You may have heard that it's important to get an annual dilated eye exam, but you may not understand what the doctor is looking for and why this particular exam is considered essential.

By widening the area of your eye through which your doctor can see, a dilated eye exam provides a good look at the inside of your eye, including the back wall or retina, the optic nerve, and all the blood vessels. Without dilating—or enlarging—the pupil, your eye exam would be like watching television through a keyhole. You might see some things, but you'd be missing a lot of the picture.

Your dilated eye exam will probably be part of a complete screening, where the doctor will:

• Inspect your eyelids, lashes, and surfaces of your eyes
• Check your vision
• Test for glaucoma by measuring the pressure in your eyes (usually by blowing a puff of air into each eye or by using eye drops to anesthetize the eye's surface and touching each one gently with an instrument called a tonometer)

None of this—including the medicated eye drops used to dilate your pupils—hurts a bit.

The eye drops work by telling the iris—the coloured muscle that surrounds each black pupil—to relax and stay wide open. Without the drops, your irises would tighten up as soon as the doctor shines a light into your eyes, and there'd be very little to see.

Once your pupils have been enlarged, the doctor uses a small beam of light and a magnifying lens to get a close-up look. If you have diabetes, your doctor will be on alert for leaking blood vessels—a possible sign of diabetic eye disease or retinopathy—or damage to the optic nerve. In addition, because the eye is the only place a doctor can get an external look at your blood vessels, your eye exam can provide clues to your overall health.

Your doctor will be looking for signs of high blood pressure, high cholesterol, or even evidence of some brain disorders. After the test, your vision will be a bit blurred and you'll be sensitive to light for a few hours. Try not to plan any activities that require precise vision (such as reading the fine print on a contract). Bring along a pair of dark glasses, or ask the doctor's office for a disposable pair. And if you think you may have trouble, ask a friend to drive you home.

Eye disease

People with diabetes are at risk for three types of eye disease: retinopathy, cataracts, and glaucoma. All of these can lead to blindness. And all can be avoided or lessened with treatment if detected early. Here are some startling statistics:

• People with diabetes are four times more likely to become blind than people without diabetes.
• Diabetic retinopathy is the leading cause of blindness in British adults.
• Eight percent of people who are legally blind lost their sight because of diabetes. 

Retinopathy, the most common eye disease for people with diabetes, is caused by damage to the blood vessels of the retina. In some cases, these vessels may swell and leak fluid. As it worsens, abnormal new blood vessels may grow on the retina's surface, causing vision loss or blindness. Unfortunately, retinopathy is very common, especially for people who have had diabetes for many years

Cataracts are another major cause of vision loss. If you have diabetes, you are twice as likely to get a cataract, which is the clouding of the lens of the eye. People with diabetes develop cataracts at an earlier age than people who do not have diabetes. Approximately 7% of people with diabetes develop cataracts. Cataracts can often be treated surgically, by replacing the eye lens with an artificial lens. It is very important to have an annual eye test so cataracts can be detected before they become severe.

Glaucoma Diabetes also increases the risk of glaucoma, which is an increase in fluid pressure inside the eye that damages the optic nerve and can lead to vision loss. 22% of people with diabetes have glaucoma, and it is more common in people with type 2 diabetes. Glaucoma can be treated with medications to reduce the fluid pressure in the eye. Laser or other types of surgery may also be effective. An annual eye test is critical in order to detect and treat glaucoma at an early stage.

Risk Factors For Eye Disease

The following groups are at an even higher risk of getting retinopathy:

• men with diabetes
• people with diabetes who have kidney disease
• pregnant women

These groups are at an increased risk of getting cataracts:

• people over age 60 with diabetes
• people who have had diabetes for many years
• people who have poor diabetes control

This group is at an increased risk of getting glaucoma:

• people with type 2 diabetes

Reducing Your Risk Of Eye Disease

You can greatly reduce your risk of diabetic eye disease by doing the following.

Practice Tight Control. As average blood sugar levels rise, so does the risk of retinopathy. The tighter your blood sugar control, the slower the onset and progression of retinopathy. A 10-year study called the Diabetes Control and Complications Trial (DCCT) showed that those who practiced tighter control experienced 76% less eye damage than those who practiced standard control. Practicing tight control can also decrease your chances of getting cataracts.

Reduce Your Blood Pressure. High blood pressure increases the risk of severe retinopathy, so if you reduce your blood pressure, you will decrease your risk of retinopathy.

Get An Annual Dilated Eye Test. People with diabetic eye disease often have no symptoms or pain until the disease becomes advanced. Your eye doctor can detect retinopathy before you have any vision impairment. The earlier retinopathy is diagnosed, the sooner you can start practicing tight control and receiving laser therapy to decrease the amount of eye damage your retinopathy will cause. It is important that the eye test involves dilation so the doctor can examine the blood vessels in the back of the eye (retina).

Treatment Of Eye Disease

Retinopathy. Laser surgery can effectively treat retinopathy by shrinking the abnormal vessels of the retina, repairing leaking vessels, or destroying those that can't be fixed. However, laser surgery is best used as a preventative measure. It often cannot restore vision that is already lost. That's why it is important to detect retinopathy in its earliest stages and treat it as soon as possible.

Cataracts. Cataracts can be treated by surgically replacing the lens of the eye with a plastic lens. This surgery restores vision 90-95% of the time.

Glaucoma. Treatment depends on the type of glaucoma. Eye drops, laser treatments, and laser surgery are often very successful.