Most Common Form of Glaucoma Has No Warning Signs

The survey says: Thirty percent of us have never heard of glaucoma; fifty percent of us have heard about it, but aren’t sure what it is, and twenty percent of us know that it’s related to elevated eye pressure, but think it is curable. The survey was conducted for the Glaucoma Research Foundation back in 2002.

Wow. Well, the truth is that glaucoma is a disease that damages your optic nerve. And, in the United States more than 120,000 people are blind because of it. The World Health Organization says that it’s the second largest cause for blindness after cataracts.

Who’s most at risk? People over 60, African Americans, those with a family history of the disease, people who have diabetes, migraines, poor blood circulation or other health issues, those who are severely nearsighted or farsighted, and those who have had an eye injury are most at risk as are those how have corneas that are thin in the center or have thinning optic nerves.

It’s not surprising that the survey found that blindness ranked third (after cancer and heart disease) as people’s major fear. And I know I say this all the time but, as is true for so many conditions, early detection is critical to preventing blindness. Medications, and often surgery, can stop the progression, but the fact is that vision lost is gone forever.

In order to understand glaucoma, it helps to understand how we see. Here’s the American Academy of Ophthalmology’s explanation:

“Light rays enter the eye through the clear cornea then through the pupil and the lens. These light rays are focused onto the retina, a light sensitive tissue lining the back of the eye. The optic nerve is connected to the retina and is made up of many nerve fibers. Signals from the retina are sent through the optic nerve to the brain where they are interpreted as the images that we see.

“In the healthy eye a clear liquid called aqueous humor circulates inside the front portion of the eye. To maintain a constant healthy eye pressure your eye continually produces a small amount of aqueous humor and an equal amount of this fluid flows out of the eye through a microscopic drain called the trabecular meshwork in the drainage angle.”

There are two major types of glaucoma. The most common type happens when the eye does not drain fluid as well as it should. “As a result, eye pressure builds and starts to damage the optic nerve. This type of glaucoma is painless and causes no vision changes at first.” AAO explains.

“Angle-closure glaucoma (also called “closed-angle glaucoma” or “narrow-angle glaucoma” happens when someone’s iris (the colored part of your eye that controls the size of your pupil to let light in) is very close to the drainage angle in their eye. The iris can end up blocking the drainage angle. When the drainage angle gets completely blocked, eye pressure rises very quickly,” AAO says.

If this happens, it’s an emergency, so you’ll want to get to the eye doctor immediately. You’ll know something’s wrong when your vision is suddenly blurry, you have severe eye pain, you have a headache, you’re nauseated, vomiting or you see rainbow-colored rings or halos around lights.

If you are younger than 40 and have no known risk factors for glaucoma, the AAO recommends you have an exam every five to ten years. At 40, you should have a baseline eye exam even if you think your vision is fine. This screening will rule out not only glaucoma, but other eye diseases such as cataracts and macular degeneration.

Those at risk should then have exams every one to three years, and the time between screenings will shorten as you get older with those ages 65 and older possibly seeing the eye doctor as often as every six to twelve months.

Glaucoma is a slowly progressing disease. However, vision loss of any kind, and particularly loss of peripheral vision as is the case with glaucoma, can impair your everyday activities. So, the question is: should you be making that appointment for an eye exam today?

Kathy Hubbard is a member of Bonner General Health Foundation Advisory Council. She can be reached at kathyleehubbard@yahoo.com.