Glaucoma is a disease that damages your eye’s optic nerve. It usually happens when fluid builds up in the front part of your eye, increasing the pressure inside the eye and damaging the optic nerve. Glaucoma is a leading cause of blindness for people over the age of 60, but blindness from glaucoma often can be prevented with early treatment.
There are several types of glaucoma:
Glaucoma is caused by high eye pressure. In the healthy eye, a clear fluid called aqueous humor circulates inside the front portion of your eye. To maintain a constant healthy eye pressure, your eye continually produces a small amount of aqueous humor while an equal amount of this fluid flows out of your eye. If you have glaucoma, the aqueous humor does not flow out of the eye properly. Fluid pressure in the eye builds up and over time causes damage to the optic nerve fibers.
Damage to the optic nerve can occur at different eye pressures in different patients. There is not one right eye pressure that is the same for everyone. Half of patients with glaucoma do not have high eye pressure when first examined. Eye pressure is not always the same—it rises and falls from moment to moment. So a single eye pressure test will fail to identify some people who have glaucoma.
When glaucoma first develops you may not have any symptoms. The disease progresses slowly, stealing your sight gradually. Fortunately, early detection and treatment can help preserve your vision.
Tonometry measures the fluid pressure inside your eye (intraocular pressure). Several methods to measure intraocular pressure are available:
You may need more-specialized tests, depending on your age, medical history and risk of developing eye disease.
Glaucoma can be treated with eye drops, medications, laser surgery, traditional surgery or a combination of these methods depending on your health and other medical conditions. The goal is to detect glaucoma early to prevent vision loss, which is irreversible once it happens.
