Nearsightednes is a condition in which the eye becomes too long from front to back, causing images to focus in front of the retina instead of directly on it. Because of this error, objects at a distance become blurry and difficult to focus on. Nearsightedness is measured in negative diopters. The farther the number is away from zero, the more extreme the nearsightedness.
Myopia, or near-sightedness, is the ability to clearly see objects up close but not those at a distance. It is an inherited condition usually detected in children between the ages of eight and twelve. Few factors outside of heredity affect this condition. Using dim light, reading too much or nutritional deficiencies do not seem to impact it one way or the other.
Myopia is usually treated with eyeglasses and contact lenses which compensate for the elongated shape of the eye allowing the light to focus properly on the retina. As children (and their eyes) grow through the teen years, the condition typically worsens and then levels off in adulthood. During this growing period, new eyeglasses may be needed as often as every six months to correct the problem.
Approximately 98% of persons who undergo refractive laser surgery obtain 20/40 or better visual acuity, which is the visual acuity required to obtain a drivers license without wearing corrective lenses. If you have been wearing contacts and/or glasses, even for a long time, it should not have an impact on your potential laser vision correction surgery.