Most people who have glaucoma don't notice any symptoms until they begin to lose some vision. As optic nerve fibers are damaged by glaucoma, small blind spots may begin to develop, usually in the side -- or peripheral -- vision. The top photo at left shows how a scene would be viewed by a person with normal vision. The bottom image shows the same scene as viewed by a person with glaucoma. Many people don't notice the blind spots until significant optic nerve damage has already occurred. If the entire nerve is destroyed, blindness results.

One type of glaucoma, acute angle-closure glaucoma, does produce noticeable symptoms. In angle-closure glaucoma, there is a rapid buildup of pressure in the eye (intraocular pressure, known as IOP), which may cause any of the following:

• blurred vision
• severe eye pain
• headache
• haloes (which may appear as rainbows) around lights
• nausea and vomiting

Angle-closure glaucoma is a rare, but serious, form of the disease. If you have any of these symptoms, call your ophthalmologist immediately. Unless treated quickly, blindness can result.

• Glaucoma is a serious eye disease. If left untreated, it can lead to vision loss and blindness.
  
• Glaucoma is the second most common cause of legal blindness in the U.S. It is the leading cause of blindness for African-Americans.
  
• Glaucoma is a chronic (ongoing) condition that requires lifelong monitoring and treatment. It is important for people with glaucoma to work with their Eye M.D.s to find a treatment plan that is right for them.
• About 2 million Americans have glaucoma -- but only half of them are aware of it.
• In glaucoma, the fluid (different from tears) that normally flows through the front section of the eye cannot drain properly. This causes a buildup of pressure in the eye that can damage the  optic nerve and lead to vision loss.
• Your Eye M.D. can use a series of  painless tests and exams to check you for glaucoma. Other tests may be done if your Eye M.D. suspects you may have glaucoma.
• Vision loss is usually preventable if glaucoma is detected early. There is no "cure" for glaucoma, but early detection and ongoing treatment can control the disease and usually preserve vision.
• Treatment for glaucoma can include  medication and/or  surgery . The best treatment for each person is determined by a number of factors, including type and severity of glaucoma, and the person's medical history and lifestyle.
• Glaucoma usually has no symptoms until vision loss has occurred.
• Approximately 80,000 Americans are legally blind from glaucoma.
  Many more have visual impairment.
• Seniors, African-Americans and those with a family history of glaucoma
  are at higher risk for the disease and should have eye exams more often.
• Medications for glaucoma -- even eye drops -- can affect the whole body and may interact with other medications. It is very important for all your doctors to be aware of any medication you take.

Please refer to the following resources to learn more about glaucoma: