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Glaucoma Fact Sheet
- What is glaucoma? Glaucoma is a disease that causes a gradual degeneration of cells that make up the optic nerve which carries visual information from the eye to the brain. As the nerve cells die, vision is slowly lost, usually beginning in the periphery. Often, the loss of vision is unnoticeable until a significant amount of nerve damage has occurred. Therefore as many as half of all people with glaucoma may be unaware of their disease.
- What causes glaucoma? 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 glaucoma, for still 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 may cause damage to the optic nerve and other parts of the eye and loss of vision.
- Who is most likely to get glaucoma? Nearly 3 million people have glaucoma, a leading cause of blindness in the U.S. Although anyone can get glaucoma, some people are at higher risk, for example, African Americans over age 40, anyone over age 60, or people with a family history of glaucoma. Studies show that glaucoma is: three to four times more likely to occur in African Americans than in Whites; About six times more likely to cause blindness in African Americans than in Whites; and 15 times more likely to cause blindness in African Americans between the ages 45-65 than in whites of the same age group.
- What are the symptoms? At first, there are no symptoms. Vision stays normal, and there is no pain. However, as the disease progresses, a person with glaucoma may notice his or her side vision gradually failing. That is, objects in front may still be seen clearly, but objects to the side may be missed. As the disease progresses, the field of vision narrows and blindness results.
- How is glaucoma detected? Many people may know of the “air puff” test or other tests used to measure eye pressure in an eye examination. But, this test alone cannot detect glaucoma. Glaucoma is found most often during a dilated eye examination. This means drops are put into the eyes during the exam to enlarge the pupils. This allows the eye care professional to see more of the inside of the eye to check for signs of glaucoma.
How can glaucoma be treated?
Although open-angle glaucoma cannot be cured, it can usually be controlled. The most common treatments include:
- Medications- These may be either in the form of eye drops or pills. Some drugs are designed to reduce pressure by slowing the flow of fluid into the eye. Others help to improve fluid drainage. For most people with glaucoma, regular use of medications will control the increased fluid pressure. But, these drugs may stop working over time. Or, they may cause side effects. If a problem occurs, the eye care professional may select other drugs, change the dose, or suggest other ways to deal with the problem.
- Laser Surgery- During laser surgery, a strong beam of light is focused on the part of the anterior chamber where the fluid leaves the eye. Small changes result, making it easier for fluid to exit the eye. Over time, the effect of laser surgery may wear off. Patients who have this form of surgery may need to keep taking glaucoma drops.
- Surgery- Surgery can also help fluid escape from the eye and thereby reduce the pressure. However, surgery is usually reserved for patients whose pressure cannot be controlled with eye drops, pills, or laser surgery.
- What can you do to protect your vision? Studies have shown that early detection and treatment of glaucoma, before it causes major vision loss, is the best way to control the disease. So, if you fall into one of the high-risk groups for the disease, make sure to have dilated eye examinations at least every one to two years by an eye care professional and annually after age 60.
Information provided by National Eye Institute, National Institutes of Health, Department of Health and Human Services
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