Our eyes contain a clear fluid called aqueous humor, which is continually produced by the eye to bathe and nourish the structures inside it. This fluid normally drains out of the eye through a series of drainage canals in a fine meshwork located around the edge of the iris (the colored part of the eye that surrounds the pupil). This fluid system should not be confused with tears, which are produced outside of the eye and are not related to glaucoma. In people with glaucoma, the fluid fails to drain, as it should, increasing the pressure inside the eye.

It might help to understand it if you think of a spring-fed lake with a stream running out at one end. The spring continually pumps water into the lake, and it drains through the stream, keeping the lake level balanced. If, for some reason, the stream becomes blocked or its opening narrows to the point that water can no longer run out freely, the water in the lake will rise. That is similar to what happens in glaucoma.

Fluid continues to be produced by the eye but is unable to flow freely out. As a result, the restricted fluid flow can cause a buildup of fluid and an increase in the pressure inside the eye called increased Intraocular pressure (IOP). In time, this increased pressure may damage the optic nerve at the back of the eye, which can cause loss of vision. If the nerve and in some cases, eventually lead to total blindness. Doctors have had significant success in treating and controlling glaucoma through the consistent use of medicine to lower the pressure in the eye.

What Factors Lead to Glaucoma? People of all ages can get glaucoma, but it is more commonly diagnosed in those who are over 55 years old, highly nearsighted, or diabetic. The tendency to develop glaucoma may be inherited. Also, if you are of African ancestry, your chance of having glaucoma is significantly greater. Having multiple risk factors increases your chance of developing glaucoma. However, people without these risk factors can still get glaucoma. Doctors and researchers do not know what causes this condition; they do know, however, that it is not caused by reading too much or in poor light, improper nutrition, or wearing contact lenses.

How Is It Treated? Open-angle glaucoma is treated effectively with medicine, usually in the form of eye drops. Some eye drops reduce pressure in the eye by making the eye produce less fluid. Less fluid flowing into the eye reduces the pressure. Other eye drops lower pressure by improving the drainage of fluid through the blocked drainage canals. Some patients may eventually need surgery if medicine does not control their glaucoma.