Too much pressure is almost never a good thing. When it's bearing down on you from work or family responsibilities, pressure can stress you out. But when pressure is building in your eye from a disease called glaucoma, it can cause permanent blindness if it's not treated.

Glaucoma involves the clear fluid in the front part of your eye, which is called the aqueous humor. Your eye constantly makes this fluid, which then drains out through a chamber in the front of the eye. When you have glaucoma, the fluid becomes blocked so it can't drain out of your eye. As the fluid builds up, it causes the pressure to rise. That pressure eventually damages the optic nerve, the important nerve which sends images to your brain and allows you to see.

There are four different types of glaucoma. The most common type is called open-angle glaucoma. Although no one knows for sure what causes it, open-angle glaucoma tends to run in families. In people with this form, the pressure rises slowly over time. Another type of glaucoma appears in babies at birth, it's called congenital glaucoma. Certain drugs and eye diseases can cause yet another form of the disease, called secondary glaucoma.

But probably the most serious form of the disease is closed-angle glaucoma. It occurs when the angle becomes suddenly blocked, causing pressure in the eye to rise sharply. This is an emergency situation. Without treatment, you can lose sight very quickly.

Because most people don't have any symptoms of glaucoma until they've already lost sight, the best way to diagnose it is by having regular eye exams. The eye doctor will dilate, or widen your pupil to get a better view of your eye. Your doctor may also do a test called tonometry to check your eye pressure, and take a photo or laser image of your optic nerve to make sure it's healthy.

The main treatment for glaucoma is eye drops to reduce the pressure inside your eyes. If drops can't control your pressure, or you have closed-angle glaucoma and your pressure rises very quickly, you'll probably need surgery, or laser therapy to open up a new drainage channel in your eye.

Your best defense against glaucoma is a good offense. See your eye doctor for a complete eye exam before you turn 40, or even sooner if you have a family history of glaucoma. That way, your doctor can spot the disease before it can steal your sight.

Version Info

  • Last reviewed on 11/23/2011
  • Alan Greene, MD, Author and Practicing Pediatrician; also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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