What is Myopia [Short-sightedness]?
Myopia is commonly known as short-sightedness. It means that the eye is unable to focus on distant objects, making them seem blurred. Vision can usually be corrected with glasses or contact lenses, or, in some cases, with laser eye surgery.
Myopia most commonly develops in childhood or early teens (between 8 and 14). The risk of developing myopia is increased if there is a family history of it. There may also be a link between myopia and prolonged close-up work, such as reading or sitting close to the television, although there is little scientific evidence for this.
Light coming into the eye is
focused onto the retina - an area on the rear wall of the eyeball. Seventy per
cent of light entering the eye is focused by the cornea (a clear dome which
forms the outer covering of the pupil). The rest is focused by the lens, which
sits behind the cornea. Normally, rays of light from a distant object are
focused by the eye onto its retina, thus resulting in a clear image. In short
sighted persons, the length of the eyeball is too great or its focusing power
too high. Hence light is now focused in front of the retina instead of ON it.
Myopia develops as the eyeball
grows, so it starts in childhood and may worsen during the teens. It normally
stops getting worse in adults.