August 01, 2015

Glaucoma

A silent thief

Glaucoma

Glaucoma is the name for a group of eye disorders that can pose a serious vision threat at any age, but especially in older adults. It's sometimes called a silent thief of sight because — in its most common forms — it can gradually rob you of your vision without you even noticing.

Glaucoma disorders damage the main nerve that connects your eye to your brain (optic nerve). How the damage occurs isn't always clear, but it's related to the pressure in your eye. As the optic nerve deteriorates, communication between the eye and the brain is disrupted. Blind spots develop in your visual field, usually starting with your peripheral vision. Eventually, the optic nerve may lose all function, leading to blindness.

Fortunately, only a small percentage of people with glaucoma ever lose their sight completely. Medical advances have made it easier to treat the disease, and if detected early, sight can usually be preserved. But having glaucoma requires regular monitoring and treatment.

Under pressure

Internal eye pressure (intraocular pressure) allows the eye to hold its shape and function properly. Think of it as air in a balloon — the right amount of air pressure keeps the balloon round and taut, but too much pressure can cause problems.

Eye pressure is determined by the flow of a fluid (aqueous humor) that circulates around the lens and cornea. The fluid drains out of the eye through a sieve-like drainage system (trabecular meshwork) at the angle where your iris and cornea meet....