Eye Condition Fact Sheet #2

Condition

Glaucoma

Description

The two main types of glaucoma are primary open angle glaucoma (POAG), and angle closure glaucoma. POAG happens when the eye’s drainage canals become clogged over time. The blockage to aqueous outflow is more subtle, involving a microscopic blockage of aqueous outflow in regions near the canal of Schlemm. If open angle glaucoma is not diagnosed and treated, it can cause a gradual loss of vision.

With angle closure glaucoma, the iris is not as wide and open as it should be. The outer edge of the iris bunches up over the drainage canals, when the pupil enlarges too much or too quickly. It is much rarer and is very different from open angle glaucoma in that the eye pressure usually rises very quickly.

Parts of visual system affected/Effects on the conditions of visual system

Internal pressure in your eye, called intraocular pressure, allows your eye to hold its shape and function properly. Intraocular pressure is like air in a balloon — too much pressure inside the balloon affects its shape and may even cause it to pop. In the case of your eye, too much pressure can damage the optic nerve.Vision loss is caused by damage to the optic nerve. The nerve acts like an electric cable with over a million wires. It is responsible for carrying images from the eye to the brain.

Treatments

There is no cure for glaucoma—yet. However, medication or surgery can slow or prevent further vision loss.Because glaucoma is often painless, people may become careless about strict use of eye drops that can control eye pressure and help prevent permanent eye damage. In fact, non-compliance with a program of prescribed glaucoma medication is a major reason for blindness resulting from glaucoma

Is condition congenital, adventitious, progressive or stable?

Progressive

Age is a large risk factor in the development of glaucoma.

Blacks are significantly more likely to get glaucoma than are whites, and they are much more likely to suffer permanent blindness as a result. Mexican-Americans also face an increased risk. Asian-Americans are at higher risk of angle-closure glaucoma, and Japanese-Americans are more prone to low-tension glaucoma. If you have a family history of glaucoma, you have a much greater risk of developing glaucoma.

Anticipated functional implications of the condition

Glaucoma can cause blindness if it is left untreated. Since glaucoma is a chronic condition, it must be monitored for life.

Glaucoma has been nicknamed the "sneaky thief of sight" because the loss of visual field often occurs gradually over a long time and may only be recognized when it is already quite advanced.

Open Angle Glaucoma

Blockage of the trabecular meshwork slows drainage of the aqueous humor, which increases intraocular pressure.

References

Ophthalmo-logy Made Ridiculously Simple, Stephen Goldberg, MD, 2001 Miani: FL pg 26.