Myopia, or nearsightedness, is an error of refraction in the eye that causes objects more than a short distance away to appear blurred. It usually results from the cornea of the eye being too far from the retina, so that images are focused in front of the retina. The error can be corrected for by concave eyeglasses or by contact lenses. Severe cases of myopia are sometimes treated by controversial surgical techniques to reshape the cornea, such as radial keratotomy or the newer laser sculpting of the cornea.