Glaucoma is an eye disease in which the internal pressure in your eyes increases enough to damage the nerve fibers in your optic nerve and cause vision loss. The increase in pressure happens when the passages that normally allow fluid in your eyes to drain become clogged or blocked. The reasons that the passages become blocked are not known.
Glaucoma is one of the leading causes of blindness in the U.S. It most often occurs in people over age 40. People with a family history of glaucoma, African Americans, and those who are very nearsighted or diabetic are at a higher risk of developing the disease. The most common type of glaucoma develops gradually and painlessly, without symptoms. A rarer type occurs rapidly and its symptoms may include blurred vision, loss of side vision, seeing colored rings around lights and pain or redness in the eyes.
Glaucoma cannot be prevented, but if diagnosed and treated early, it can be controlled. Vision lost to glaucoma cannot be restored. That is why the American Optometric Association recommends annual eye examinations for people at risk for glaucoma (your doctor may, depending on your condition, recommend more frequent examinations). A comprehensive optometric examination will include a tonometry test to measure the pressure in your eyes; an examination of the inside of your eyes and optic nerves; and a visual field test to check for changes in central and side vision.
The treatment for glaucoma includes prescription eye drops and medicines to lower the pressure in your eyes. In some cases, laser treatment or surgery may be effective in reducing pressure.