Glaucoma: Silent thief of sight
Article page |
Health page |
Glaucoma is an eye disorder in which the optic
nerve suffers damage, permanently impacting vision in the affected eye(s) and
progressing to complete blindness if untreated. It is often, but not always,
associated with increased pressure of the fluid in the eye.
What is glaucoma?
Glaucoma is a group of eye diseases in which the normal fluid pressure inside the eyes slowly rises, leading to vision loss or even blindness. Open-angle glaucoma is the most common form of the disease.
What causes it?
Clear fluid flows in and out of small space at the front of the eye called the anterior chamber. This fluid bathes and nourishes nearby tissues. If this fluid drains too slowly, pressure builds up and damages the optic nerve. Though this buildup may lead to an increase in eye pressure, the effect of pressure on the optic nerve differs from person to person. Some people may get optic nerve damage at low pressure levels while others tolerate higher pressure levels.
Who is most likely to get it?
Glaucoma is a leading cause of blindness in the United States. Although anyone can get glaucoma, the following people are at higher risk:
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 worsens, the field of vision narrows and blindness results.
How is it 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 an eye examination through dilated pupils. Dilating pupils involves putting drops into the eyes during the exam to enlarge the pupils. This procedure allows the eye care professional to see more of the inside of the eye to check for signs of glaucoma.
How can it be treated?
Although open-angle glaucoma cannot be cured, it can usually be controlled. The most common treatments are as follows:
What research is being done?
Scientists in the United States are conducting research to learn what causes glaucoma and to improve its diagnosis and treatment. For example, researchers have discovered genes that could help explain how glaucoma damages the eye.
NEI is funding a number of studies to find out what causes fluid pressure to increase in the eye. By learning more about this process, doctors may be able to find the exact cause of the disease and learn better how to prevent and treat it. NEI supports studies to learn more about who is likely to get glaucoma, when to treat people with increased pressure, and which treatment to use first. NEI also supports clinical trials of new drugs and surgical techniques that show promise against glaucoma.
( Courtesy: National Eye Institute http://www.nei.nih.gov/ )