Nearsightedness, also known as Myopia, occurs when the light rays focus in front of the retina instead of on the retina. This is caused because the cornea is too steep or the eye is too long.
Myopia is often first detected between eight and twelve years of age. As the body grows, the nearsightedness often increases and later stabilizes in adulthood. Changes in glasses or contact lens prescriptions are necessary during growth spurts.
The symptoms include blurred vision in the distance and difficulty seeing street signs, chalk boards, movies, television, etc. It is often diagnosed during vision screenings at school.
Treatment for myopia involves a lens (eyeglasses or contact lens) that correctly focuses the light rays onto the retina.