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 you 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 Canada. It most often occurs in people over the age of 40. People with a family history of glaucoma, African Americans, and those who are very near sighted 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 coloured rings around lights and pain or redness in the eyes.