The condition in which the fluids within the eye develop a higher than normal pressure is called glaucoma. If glaucoma is not treated, the increased pressure is transmitted to the optic nerves and can produce irreversible loss of vision, even complete blindness. Glaucoma causes 10% of the blindness that occurs in the United States. Although glaucoma is not a result of an aging change in the eye, it does occur with increasing frequency after age 40; it occurs in 4% of the population by age 65, and in 15% by age 80. African-Americans are far more commonly affected than whites.
Of the several different varieties of glaucoma, openangle glaucoma causes most of the problems in elderly patients. Open-angle glaucoma usually produces no symptoms for a long period. Unlike other varieties of glaucoma, it does not cause pain in the eye. Gradually, there is a loss of part of what physicians call the visual field. This usually happens in both eyes, and it may develop so slowly that you remain unaware of the visual field loss until it becomes advanced and irreversible.
Some patients are at particular risk for glaucoma. These include patients with a family history of glaucoma (a parent, brother, or sister) and patients who are receiving long-term therapy with steroid medications. Patients with high blood pressure, diabetes, and nearsightedness (myopia) are also more susceptible to the development of glaucoma.
All patients over age 40 and particularly those at special risk need a regular examination for the presence of glaucoma. Detection of the earliest stages of the disease requires the use of special tools to measure pressure and careful examination of the back of the eye with an ophthalmoscope.
Important Points in Treatment
When elevated pressure is found, it is treated even if there are no symptoms traceable to the increased pressure. It is best to begin treatment before visual changes can be found. The changes in vision are not reversible. Treatment can involve eye drops (topical therapy), systemic drugs, or both. Either kind of therapy can produce side effects and beneficial effects. There is a need to document that the therapy is effective by repeated examination of the eye and its pressures. Therefore, glaucoma therapy is done under the care of an ophthalmologist.