Glaucoma damages the eye's optic nerve. It is a leading cause of blindness in the United States. It usually happens when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Often there are no symptoms at first, but a comprehensive eye exam can detect it. People at risk should get eye exams at least every two years. They include African Americans over age 40 People over age 60, especially Mexican Americans People with a family history of glaucoma Early treatment can help protect your eyes against vision loss. Treatments usually include prescription eyedrops and/or surgery.