Glaucoma is a group of eye diseases that cause damage to the optic nerve, which left untreated, can initially lead to loss of peripheral vision and possibly to blindness. It can occur when the internal pressure of the eye increases enough to damage nerve fibers in the optic nerve. Glaucoma usually develops without pain or symptoms, and while it cannot be prevented, it can be controlled to prevent or minimize continued vision loss.
There are two major types of glaucoma and numerous others. Primary open angle glaucoma is the most common, developing slowly and painlessly, so it can destroy vision without any warning symptoms. The second is acute angle closure glaucoma which occurs with a sudden blockage of drainage channels causing a rapid pressure increase. Symptoms may include blurred vision, haloes around lights, pain or redness of the eye and sometimes nausea.
The diagnosis of glaucoma starts with a comprehensive eye exam at which time the intraocular pressure is painlessly measured. Elevated intraocular pressure is a risk factor for glaucoma. Pachymetry or the measurement of the corneal thickness allows us to confirm the pressure readings. Computerized visual field testing helps detect decreased sensitivity in one’s peripheral vision, an early sign of glaucoma. New technologies, such as the OCT (ocular coherent tomography) allow us to visualize and measure the optic nerve as well as the thickness of the retinal nerve fiber layer, which, if deficient, may indicate glaucoma. People of all ages can develop glaucoma, but it most frequently occurs in people:
- who are over age 40
- who have a family history of glaucoma
- who are very nearsighted
- who are diabetic
- who are black
Typically, the first line of therapy for glaucoma is the use of pressure lowering eye drops. These may be taken individually or in combination to best lower the intraocular pressure. Sometimes, laser or surgery is required to achieve the best results. All treatments are designed to prevent the loss of vision, but early detection and treatment are of greatest importance.