General Information About Glaucoma

What Is Glaucoma?

Glaucoma is an eye disease caused by increased pressure within the eye. It is one of the most common causes of blindness and affects 1 in 100 Canadians over age 40. Although it often occurs in older people, it can develop at any age.

People with glaucoma probably lose their sight because increased pressure in the eye and other factors (such as poor blood flow) affect the optic nerve at the back of the eye. The eye slowly loses nerve function, and loss of side (peripheral) vision. This occurs painlessly, even unnoticeably.

What causes glaucoma?

No one knows exactly what causes glaucoma, but some factors raise your chances of having it:

• age
• family history
• if you are of African or Hispanic descent
• nearsightedness
• poor health (such as early heart attack or stroke)
• raised intraocular pressure, (IOP). This is a buildup of pressure inside the eye caused when a blockage stops fluid from flowing out of the eye.
  

It is important to know about glaucoma, especially if you have any of the risk factors listed above, or have had a serious eye injury or eye disease. Some drugs, such as steroids, can also cause glaucoma.

There are many myths about glaucoma. Here are some facts:

• Glaucoma is not caused by stress or anxiety.
• Glaucoma is not caused by poor nutrition or lack of vitamins.
• Glaucoma is not a form of cancer.
• Using your eyes does not make glaucoma worse.
• If you can see you may still have glaucoma.
  

How is glaucoma diagnosed?

Any vision problem that your glasses or contact lenses don’t correct may be a sign of glaucoma. You should have regular eye exams by a qualified eye care professional to prevent this disease that can blind. OCT Testing is an important test used to diagnose and follow glaucoma.

Open-angle glaucoma

Open-angle glaucoma is the most common type. Patients don’t usually notice any symptoms until it is very advanced. People with this type of glaucoma can drive, read, and do most of their daily activities, because their vision loss isn’t very obvious until it is too late. This loss of vision cannot be reversed and is permanent, so it is important to detect and treat it early to preserve whatever vision remains. Tests for glaucoma are quick and painless. The doctor measures your IOP with a special instrument called a tonometer. Depending on the results, you may need more tests, and eventually treatment may be started.

Closed-angle glaucoma

Closed-angle glaucoma is less common. Your eye care professional can often tell if you have the eye structure that leads to this problem and can recommend laser therapy to prevent it. The symptoms of acute closed-angle glaucoma include sudden dull, aching pain over one eye, a change in your vision, and seeing blurring and haloes around lights. If this happens, it is an emergency and you should see a eye care professional or go to an emergency room right away.

How is glaucoma treated?

Open-angle glaucoma

Treatment commonly starts with eye drops to decrease the IOP. You may need to change from one type of drop to another. This is a lifelong disease, and your eyes must be checked regularly to make sure you are getting the best treatment. You must follow the strict medication schedule your doctor gives you. Be sure you understand the directions you get from your doctor. If the medications don’t keep your IOP under control, you may need laser therapy. In a small number of people surgery will be needed.

Closed-angle glaucoma

To treat an attack, your doctor has to decrease the IOP with medications before there is permanent damage to your eyesight. He or she will then use a laser to make a microscopic opening in the coloured part of your eye (the iris) to prevent another attack. This procedure is called an “iridotomy.”

It is important to stay healthy, because your general health may affect your glaucoma. To prevent drug interactions, tell your family doctor and ophthalmologist about all the medications you take.

nformation Courtesy of:
Canadian Ophthalmological Society
1525 Carling Avenue, Suite 610
Ottawa, Ontario Canada K1Z 8R9