Glaucoma is an eye disease in which fluid pressure in the eye damages the optic nerve.  This nerve damage first affects peripheral vision, but eventually can cause blindness.

What causes glaucoma?

The space inside the front of the eye between the cornea and the iris is called the anterior chamber.  Clear fluid called aqueous flows in and out of the anterior chamber to bathe and nourish the anterior part of the eye.  In glaucoma, the aqueous fails to drain from the eye quickly enough, causing the pressure inside the eye to build up.  Over time, the increased  pressure inside the eye damages the sensitive optic nerve at the back of the eye and causes vision loss.

What are the symptoms of glaucoma?

In the most common form of glaucoma (called chronic open angle glaucoma), there are no early symptoms.  The eyes appear normal, vision is normal, and there is no pain or discomfort.  As glaucoma progresses, peripheral vision is lost.  As this form of glaucoma progresses, the visual field continues to narrow, causing tunnel vision and blindness.

There is a less common form of glaucoma called acute angle closure glaucoma.  This form strikes suddenly and usually involves severe eye pain and a much quicker loss of vision.

How common is glaucoma?

Approximately three million people in the United States have glaucoma.  It is a leading cause of blindness among adults in the U.S.

Risk factors include:

• Anyone over the age of 60

• African Americans over the age of 40

• A family history of glaucoma

• Diabetes

African Americans have a particularly high risk of glaucoma - it occurs about five times more frequently among African Americans than Caucasians, and African Americans between the ages of 45 and 65 are 15 times more likely to go blind from glaucoma than Caucasians of the same age group.

What is the treatment for glaucoma?

There is no cure for glaucoma, but it can be controlled with prompt treatment.  Depending on the type and severity of the condition, glaucoma is treated in one or several of the following ways:

1.      Medicine - Glaucoma medicines may be in the form of eye drops, pills, or both.  Some medicines reduce pressure by improving aqueous drainage from the eye; others work by slowing aqueous production.

2.      Laser surgery - Laser surgery may be used to create wider openings in the aqueous drainage structures within the eye so the aqueous can exit the eye more easily.

3.      Other microsurgery - Other microsurgical techniques may be used to increase aqueous outflow if drugs and/or laser surgery are contraindicated or cannot sufficiently reduce eye pressure.

None of the treatment options for glaucoma can restore vision that has already been lost because of the disease.  Treatment is performed to prevent further vision loss.

Can glaucoma be prevented?

Routine eye exams are your best prevention against glaucoma.  During your exam, your eye doctor will perform a test called tonometry to measure the pressure inside your eyes.  He/she will also examine the appearance of the optic nerve at the back of the eye.  If glaucoma is suspected, a visual field test may also be performed to evaluate your peripheral and central vision. 

Remember, the most common form of glaucoma has no symptoms.  By the time you notice a change in your vision from glaucoma, it's too late.  See your optometrist or ophthalmologist as directed for routine glaucoma testing to protect your eyes from this serious sight-threatening disease.