Glaucoma is an eye disease where the pressure in your eyes can increase enough to damage the nerve fibers in your optic nerve and cause vision loss. The increase in pressure occurs when the passages that normally allow fluid in your eyes to drain become clogged or blocked. The reasons that the passages become blocked are currently not known.

Glaucoma is one of the leading causes of blindness in the United States today. It occurs more in people over age 40. People with a family history of glaucoma, African Americans, and those who are very nearsighted and/or diabetic are at a higher risk of developing the disease.

The most common type of glaucoma develops gradually and painlessly, without symptoms. A more rare type occurs quickly and its symptoms can include blurred vision, loss of side vision, seeing colored rings around lights and pain or redness in the eyes.