Glaucoma is a leading cause of irreversible vision loss in the United States. The American Academy of Ophthalmology estimates that 80,000 Americans are blind because of glaucoma. Another one million people in the United States are at risk for going blind because they don't know they have glaucoma.
Glaucoma does not give early warning signs of possible vision loss, leaving people unaware that the disease is slowly stealing their vision. In the absence of symptoms, diagnostic tests are the only way to know if you have glaucoma. Open-angle glaucoma (the most common type of glaucoma) has no symptoms. It causes no pain. But, damage is slowly happening.
What's Going On?
At the front of the eye, there is a small space called the anterior chamber. Clear fluid flows in and out of the chamber to bathe and nourish nearby tissues. In open-angle glaucoma, for unknown reasons, the fluid drains too slowly out of the eye.
As the fluid builds up, the pressure inside the eye rises. Unless this pressure is controlled, it can cause damage to the optic nerve and other parts of the eye. As optic nerve fibers are damaged by glaucoma, small blind spots can begin to develop.
The loss of vision is often gradual, but irreversible. It's important to note that increased eye pressure means that you are at risk for glaucoma, but it does not mean you have the disease. You have glaucoma only if the optic nerve is damaged. If you have increased pressure but no damage to the optic nerve, you do not have glaucoma, even though you are at risk for it.
Whether or not you develop glaucoma depends on the level of pressure your optic nerve can tolerate without being damaged. This level is different for each person. That's why a comprehensive dilated eye exam is very important. It can reveal more risk factors, such as high eye pressure, thinness of the cornea, and abnormal optic nerve anatomy.
|
 |
|
The optic nerve is a bundle of more than one million nerve fibers. It connects the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.
|
Disease Progression
As the disease progresses, people with glaucoma might notice their side vision gradually failing. Specifically, objects in front might still be seen clearly, but objects to the side and out of the corner of the eye might be missed. Without treatment, people with glaucoma will slowly lose their peripheral (side) vision. They seem to be looking through a tunnel. Over time, straight-ahead vision can decrease until no vision remains.
 |
 |
| Normal vision |
Same scene as viewed by a person with glaucoma |
Glaucoma can develop in one or both eyes.
Regular eye exams are the best way to detect glaucoma before your vision is affected. Certainly, if you experience decreased peripheral vision you should see an eye care specialist right away. With treatment, glaucoma usually can be controlled.
If you are being treated for glaucoma, be sure to take your glaucoma medicine every day and see your eye care professional regularly. If there is vision loss, treatment can also protect remaining vision. Also, low vision services and devices are available that might help you make the most of your remaining vision. Ask your healthcare provider for a referral to a specialist in low vision. |
