Understanding Glaucoma

by
Brian Campbell

According to the Canadian Association of Optometrists, Glaucoma is one of the leading causes of blindness in Canada. Called the “Silent Thief of Sight”, glaucoma is actually the name given to a group of diseases that cause progressive damage to the optic nerve, eventually leading to vision loss and even blindness. Since January is Glaucoma Awareness Month, this would be an ideal time to study the causes and prevention of this condition.

What Do We Know About Glaucoma?

As of yet, we still don’t know the precise cause of glaucoma. For the most part, glaucoma is associated with high fluid pressure in the eye, but there are some exceptions to that rule.

There are four known types of glaucoma: Primary Open-Angle Glaucoma, is the most common type and is caused when either the aqueous fluid produced by the eye is over produced, or if it does not drain properly. This gradual build-up of fluid puts pressure on the optic nerve. It often happens so gradually that a person may not notice any symptoms until vision is impaired. The second type is Angle-Closure Glaucoma, which is caused when fluid drainage between the iris and cornea is blocked, creating pressure on the optic nerve. This blockage can happen gradually, as a person ages, or may come on suddenly and potentially cause vision loss within 24 hours. Another form of glaucoma is known as Secondary Glaucoma, and is usually brought on by an infection or injury that causes a build-up of pressure. The final type is Normal-Tension Glaucoma, which develops even though eye pressure remains normal. Although the actual cause is unknown, it is believed that it may be the result of an overly sensitive optic nerve, or potentially by a reduction in blood supply to the optic nerve.

Who is at Risk for Developing Glaucoma?

People at risk of developing glaucoma include anyone over 40 years old, those of African-Canadian, Inuit, Russian, Scandinavian, Irish, Hispanic or Japanese descent, and those who have a family history of glaucoma. You are also at risk if you already have an eye condition, and in particular Myopia (Nearsightedness) or Hyperopia (Farsightedness). People who have an eye injury or trauma can develop glaucoma. There is also a connection between glaucoma and diabetes and/or high blood pressure. Those using corticosteroids for prolonged periods may also be at risk.

What Can I Do To Protect Myself From Developing Glaucoma?

The best defense against glaucoma is to take care of your health. Regular exercise and a healthy diet will go a long way to prevent health issues related to glaucoma such as diabetes and high blood pressure. Use proper eye protection when at work and play to prevent injury. But, since so little is known about the cause of glaucoma, and since it often occurs with little or no symptoms, your best protection is early detection. Remember to see your optometrist regularly and don’t take chances with your vision.