Did you know that one type of glaucoma has no symptoms? This eye disease has been dubbed the silent thief of sight. That’s why it’s so important to schedule regular eye exams with your eye doctor—and live a healthy lifestyle.
More than 400,000 Canadians have some form of glaucoma. While glaucoma can usually be controlled if caught in the early stages, this eye disease is the second leading cause of vision loss among older Canadians.
What causes glaucoma?
Glaucoma is the result of a malfunction in the drainage system of your eye. Your eyes produce a fluid that flows out of your eye through a tiny spot between the cornea and iris, called the angle. The fluid is then absorbed into the circulatory system. This continuous flow allows for a balanced pressure (called intraocular pressure) inside the eye. Sometimes the fluid doesn’t drain efficiently, and as it accumulates in the eye, the intraocular pressure climbs. This puts pressure on the optic nerve and damages it.
About 90 percent of those who have glaucoma have primary open-angle glaucoma. The remaining 10 percent have more uncommon forms, such as primary acute closed-angle glaucoma and secondary glaucoma.
No warning signs
Unfortunately, there aren’t any symptoms or warning signs for primary open-angle glaucoma. “It is often called the silent thief of sight because, initially, there are no symptoms,” explains Toronto ophthalmologist Yvonne Buys, MD. “By the time patients start losing their vision, they already have advanced disease.”
With glaucoma, vision loss starts gradually around the edges, the periphery. As the damage to the optic nerve progresses, the field of vision continues to narrow until all vision is lost.
It’s important to know that while primary open-angle glaucoma doesn’t have symptoms, the rarer acute closed-angle glaucoma does. This type of glaucoma is a medical emergency. If you experience these symptoms, you should go to an emergency department immediately:
- sudden sharp pain in your eye
- nausea and vomiting
- blurry vision
- redness in the eye
- halos around lights
How can you reduce the risk of getting glaucoma?
Modifiable risk factors
There are a few modifiable risk factors that you may have some control over, such as
- injury or infection in the eye
- high levels of steroid or corticosteroid use
- hypertension (high blood pressure)
- low thyroid function
Controlling diabetes, hypertension, and low thyroid function may help you reduce the risk of developing glaucoma. Taking medication as prescribed is vital, as is exercising and eating a healthy diet. Complementary and natural therapies, such as yoga and meditation, may also help you manage hypertension and even diabetes.
Non-modifiable risk factors
Some risk factors for glaucoma are non-modifiable. You can’t change them. If you have one or more of these risk factors, take special care to have your eyes checked on a regular basis. “The best way to protect yourself is to get your glaucoma diagnosed early,” Buys says.
The non-modifiable risk factors are
- having a naturally high intraocular pressure
- being older
- having a family history of glaucoma
- being female (twice as many women develop glaucoma than men)
- being nearsighted
- being of a certain ethnicity
At increased risk
If you belong to one of these ethnic groups, you have an increased risk of developing certain types of glaucoma.
|Ethnicity||Type of glaucoma|
|Black or Hispanic||primary open-angle glaucoma|
|Asian or Inuit||acute closed-angle glaucoma|
|Japanese||normal tension glaucoma|
Testing for glaucoma
Because there are no symptoms for primary open-angle glaucoma, an eye examination by an optometrist or ophthalmologist is the only way to catch it before vision is affected. Buys suggests that people over the age of 50 should have a comprehensive eye exam at least every one or two years. However, those with risk factors should start earlier, around the age of 40, and go once a year, she says. The eye exam is painless and doesn’t take long.
Your eye doctor will examine how well you see and if you have lost any peripheral vision. He or she will also look directly into your eye to check for any abnormalities within the eye.
This test measures the intraocular pressure and can be done two ways by your eye doctor. The first is with a machine that directs a quick puff of air to the eye. The machine calculates how the light changes in the eye when the air makes contact. For the other method, drops are put in the eye to numb the area. A small pencil-like device is used to lightly touch the surface of the eye to take a pressure reading.
Can glaucoma be prevented?
According to Buys, there’s nothing you can do to prevent glaucoma from developing in the first place. Early recognition is the key. “A lot of people explore different things in the diet in terms of vitamins and herbal medications. The more common ones that I hear people talk about are ginkgo and blueberries, but there is no evidence yet to show that they will slow down glaucoma progression or that they’ll make your eye pressure go down,” she says.
Some vitamins and supplements may play a role in overall eye health, however, helping to limit the development of other aging-related eye diseases such as cataracts and age-related macular degeneration (AMD). Your local health food store or natural health care practitioner can help guide you to the right products for you.
While glaucoma isn’t directly related to other eye diseases, they do share the age risk factor. Buys explains that people who have glaucoma are older, so they’re more likely to also have cataracts and perhaps AMD.
The goal of glaucoma treatment is to get the intraoucular pressure to drop or to stop it from progressing. There are several types of eye drops that may be prescribed. Some only need to be used once or twice a day, others more frequently.
“Glaucoma treatment is, in general, very effective and it does prevent vision loss,” Buys says. “However, it requires that patients take their medications as prescribed, and they come for routine eye exams at least every six months.”
Buys also encourages people who try alternative therapies to tell their doctor that they are doing so. “Some of these alternative therapies could have adverse effects that they might not be aware of.”
As effective as the drops are overall, they don’t work for everyone. If this is the case for you, and your intraocular pressure doesn’t go down, your eye doctor may recommend laser or conventional surgery to open a pathway for the fluid to leave the eye.
Diagnosing glaucoma in its early stages is essential to prevent vision loss. Plan to undergo a simple eye examination every year or two. It could help save your sight.
Eating for eye health
Some nutrients may help promote healthy vision and may reduce the risk of developing age-related eye diseases, such as cataracts and AMD.
Foods found in
|lutein and zeaxanthin||
|omega-3 fatty acids||
These nutrients can also be found in supplement form at your natural health store. Consult your eye doctor or health care practitioner to determine which supplements may be right for you.