Common Visual Conditions: Nearsightedness
Nearsightedness (myopia) occurs when your eyeball is too long or your cornea curves too much. For nearsighted people, images enter the front of the eye and focus directly in front of the retina. This results in distant objects being blurry, while near objects appear clearly.
Nearsightedness most often begins in the pre-teenage years. Heredity and, possibly, environmental factors cause nearsightedness. Eyeglasses or contact lenses improve vision by properly focusing distant objects clearly on the retina.