What is glaucoma?

Glaucoma is a disease of the optic nerve--the part of the eye that carries the images we see to the brain.  The optic nerve is made up of many nerve fibers, like an electric cable containing numerous wires.  When damage to the optic nerve fibers occurs, blind stops develop.  These blind sports usually go undetected until the optic nerve is significantly damaged.  If the entire nerve is destroyed, blindness results.

Early detection and treatment by your ophthalmologist (Eye M.D.) are the keys to preventing optic nerve damage and blindness from glaucoma.

Glaucoma is the leading cause of blindness in the United States, especially for older people.  But loss of sight from glaucoma can often be prevented with early treatment.



What causes glaucoma?

Clear liquid called aqueous humor circulates inside the front portion of the eye.  To maintain a healthy level of pressure within the eye, a small amount of this fluid is produced constantly while an equal amount flows out of the eye through a microscopic drainage system. (This liquid is not part of the tears on the outer surface of the eye.)

Because the eye is a closed structure, if the drainage area for the aqueous humor--called the drainage angle--is blocked, the excess fluid cannot flow out of the eye.  Fluid pressure within the eye increases, pushing against the optic nerve and causing damage.



What are the different types of glaucoma?

Primary open-angle glaucoma.  This is the most common form of glaucoma in the United States.  The risk of developing primary open-angle glaucoma increases with age.  The drainage angle of the eye becomes less efficient over time, and pressure within the eye gradually increases, which can damage the optic nerve.