Glaucoma: A common eye condition in which the fluid pressure inside the eyes rises because of slowed fluid drainage from the eye. If untreated, it may damage the optic nerve and other parts of the eye, causing the loss of vision or even blindness.

The elderly, African-Americans, and people with family histories of the disease are at greatest risk. There are no symptoms in the early stage of glaucoma. Glaucoma is often called "the sneak thief of sight." Often, by the time the patient notices vision loss, glaucoma can only be halted, not reversed.

There are several different types of glaucoma, including open-angle glaucoma and acute angle-closure glaucoma, Open-angle glaucoma is the common adult-onset type of glaucoma. Acute angle-closure glaucoma is a less common form of glaucoma but one that can rapidly impair vision.

The treatment of glaucoma may include medication, surgery, or laser surgery. Eyedrops or pills alone can usually control glaucoma, although they cannot cure it. Some drugs are designed to reduce pressure by slowing the flow of fluid into the eye, while others help to improve fluid drainage. Surgery to help fluid escape from the eye was once extensively used, but except for laser surgery, it is now reserved for the most difficult cases. In laser surgery for glaucoma, a laser beam of light is focused on the part of the anterior chamber where the fluid leaves the eye. This results in a series of small changes, making it easier for fluid to exit. Over time, the effect of laser surgery may wear off.

See also: Acute angle-closure glaucoma, Glaucoma detection, Normal tension glaucoma, Open-angle glaucoma.