What Is Glaucoma? Can You Prevent It from Getting Worse?
Glaucoma is an eye disease that leads to a progressive degeneration of the optic nerve. Discover what glaucoma is and how to prevent it from worsening today. One of the leading causes of blindness in Canada, glaucoma is generally developed by people over the age of 40.
A few numbers…
According to the World Health Organization (WHO), glaucoma affects more than 60 million people worldwide.
In Canada, more than 400 000 people are suffering from glaucoma according to the Canadian Association of Optometrists. The average of people who have glaucoma are 1% for people over 40 years of age, 5% for people over 70 and 10% of people 80 or older. Even though there are many different types of glaucoma, open-angled glaucoma remains the most widespread.
What exactly is glaucoma?
Glaucoma is generally associated with increased fluid pressure in the eye. Increased pressure, which is due to inadequate secretion of a fluid called “aqueous humor”. This same aqueous humor poses a risk of accumulating and adding excessive pressure to the optic nerve which transmits images to the brain. Since the optic nerve is so fragile and irreplaceable if damaged, it is important that any issues be detected and treated early before it’s too late.
As mentioned before, there are different types of glaucoma, each one with distinct characteristics. The two types most widespread: primary open-angle glaucoma and angle-closure glaucoma.
Primary open-angle glaucoma
This is the most common form of glaucoma. This type of glaucoma happens when the eyes’ drainage system is no longer effective and can’t dispose of the excess aqueous humor properly. The optic nerve transmits all the information the eye sees and sends that information to the brain. When the optic nerve is damaged, the amount and quality of information sent to the brain is decreased and loss of vision occurs. Peripheral vision is usually the first affected followed by the central vision.
This type of glaucoma, also known as, closed-angle glaucoma or narrow angle glaucoma, does not occur as often but is considered a medical emergency that can cause vision loss within a day. Angle-closure glaucoma happens when the drainage angle in the eye (formed by the cornea and the iris) closes or becomes blocked. With age, the lens in the eye becomes larger, pushing the iris forward and narrowing the space between the iris and the cornea. As this angle narrows, the aqueous fluid is blocked from exiting through the drainage system, resulting in a buildup of fluid and an increase in eye pressure. Angle-closure glaucoma can progress gradually or appear suddenly.
Symptoms and causes
If in the beginning, there don’t seem to be any symptoms, it is in the latter stages that people with glaucoma start to get the impression that they are looking through a tunnel and that their vision is restricted. Consequently, they become sensitive to high intensity lighting like sunlight or artificial lighting. Glaucoma is a vicious disease, there are no tell-tale signs, eye pressure increases slowly without swelling of the cornea therefore it is difficult to prevent it. Generally, the condition goes unnoticed and the person doesn’t realize that they are progressively losing their vision.
Having said that, there are symptoms that can help prevent closed-angle glaucoma. Among the symptoms are nausea, ocular pain, blurred vision are crucial signs that closed-angle glaucoma is developing in the eyes.
It is difficult to determine the exact causes of glaucoma, however, we do know that heredity, diabetes, cardiovascular issues, tobacco consumption or even certain medications can cause glaucoma.
Preventing and treating glaucoma
Glaucoma can be dangerous if not treated immediately. A complete eye exam is often the only way to detect it. The optometrist can check the intraocular pressure (tonometry) to make sure it is stable. The optometrist can also examine the interior of the eye to see if the retina and optic nerve are in good health. The doctor can also verify if the drainage angle is blocked or not.
As far as treatments go, there is no miracle cure for advanced stages of glaucoma, as previously stated, if the optic nerve is affected, it is not repairable.
That being said, there are medications that can reduce high intraocular pressure. Laser surgery enables the fluid inside the eye to circulate therefore making the draining process easier. Also, daily usage of ophthalmic drops is usually effective for preserving vision.
Ultimately, regular eye exams with your optometrist are highly recommended for early detection and prevention of glaucoma.