The Glaucoma Research Foundation estimates that there are more than 65 million cases of glaucoma worldwide. Some types of glaucoma stem from increased pressure inside the eye, but all cause damage to the optic nerve, which carries visual information from the eye to the brain. Glaucoma can cause permanent and irreversible loss of vision, including blindness.
Statistics
The Mayo Clinic says that glaucoma is the second most common cause of blindness. Although glaucoma is treatable, the Glaucoma Research Foundation says that 10 percent of treated glaucoma patients eventually lose their vision; in the United States, about 9 to 12 percent of all blind people lost their vision to glaucoma, amounting to about 120,000 cases.
Progression
According to the Mayo Clinic, loss of vision from glaucoma generally follows a predictable course: blind spots in peripheral vision are followed by tunnel vision, which gradually develops into total blindness. The Glaucoma Research Foundation says that patients in the early stages of glaucoma often fail to realize their loss of peripheral vision because they compensate by turning their heads from side to side. When visual loss occurs, treatment cannot restore it but only prevent or slow further loss.
Time Frame
Open-angle glaucoma is the most common type. With no symptoms except gradual loss of vision, untreated open-angle glaucoma can take years to progress to total blindness. On the other hand, the second most common type of glaucoma, angle-closure glaucoma, begins suddenly with severe eye pain, nausea and blurred vision. Angle-closure glaucoma is a medical emergency, and patients need to seek care as soon as possible. Without treatment, angle-closure glaucoma can cause permanent, irreversible blindness in as little as one to two days, according to the National Eye Institute.
Race
The National Eye Institute says that glaucoma is about 4 times more likely to cause blindness in African Americans than in whites. African Americans in the 45 to 64 age range have a 15-fold greater risk of becoming blind from glaucoma compared with whites in the same age range. Mexican Americans older than 60 years of age also have an increased risk for glaucoma.
Prevention
The Glaucoma Research Foundation estimates that more than 4 million people in the United States have glaucoma, but half of them do not realize it. Early stages of glaucoma have no symptoms but can still cause damage to the optic nerve. The National Eye Institute urges people in high-risk groups to have glaucoma screenings once every two years for early detection of glaucoma. Early detection and treatment can limit the damage to the optic nerve and preserve or slow the loss of vision.
