Glaucoma, the second leading cause of blindness, is a complex disease in which damage to the optic nerve leads to progressive, irreversible vision loss. Glaucoma is comprised of a group of eye conditions that damage the optic nerve, the health of which is vital for good vision. This damage is often caused by an abnormally high pressure in the eyes. The disease can occur at any age but is more common in older adults. Many forms of glaucoma have no warning signs, and its effect is so gradual that people with glaucoma may not notice a change in vision and may not receive glaucoma treatment until the condition is at an advanced stage.
Causes & Risk Factors
Glaucoma is the result of damage to the optic nerve. As this nerve gradually deteriorates, blind spots develop in a patient’s visual field. For reasons that aren’t fully understand, this nerve damage is usually related to increased pressure in the eye. Elevated eye pressure is due to a buildup of a fluid (aqueous humor) that flows throughout the inside of the eye. Glaucoma also tends to run in families. In some people, scientists have identified genes related to high eye pressure and optic nerve damage.
Symptoms
For open-angle glaucoma, symptoms include patchy blind spots in peripheral or central vision, as well as tunnel vision in advanced stages
For acute angle-closure glaucoma, symptoms include severe headaches, eye pain and redness, nausea and vomiting, blurred vision, and the appearance of halos around lights
For normal-tension glaucoma, for unknown reasons the optic nerve becomes damaged even though eye pressure is within the normal range