Glaucoma is a type of progressive eye damage in which optic nerve cells are damaged by excess fluid pressure in the eyeball. It's the second leading cause of blindness in North America, behind diabetes.
Glaucoma often runs in families. There are several types of the disease and each is caused by a different disease process that tends to affect different racial groups. Overall, people of African origin are more likely than Caucasians to get glaucoma.
Other risk factors for developing glaucoma include being over 40 years old, having high intraocular pressure (IOP; pressure inside the eye), myopia (nearsightedness), diabetes, high blood pressure, and a history of an eye injury.