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Alternative Names Return to topMyopia; Shortsightedness
Definition Return to top
Nearsightedness is when the eyes focus incorrectly, making distant objects appear blurred.
Causes Return to top
A nearsighted person sees near objects clearly, while objects in the distance are blurred. As a result, someone with myopia tends to squint when viewing far away objects. This characteristic is the basis of the word "myopia," which comes from two Greek words: myein, meaning shut, and ops, meaning eye.
A nearsighted person can easily read the Jaeger eye chart (the chart for near reading), but finds the Snellen eye chart (the chart for distance) difficult to read. This blurred vision results when the visual image is focused in front of the retina, rather than directly on it.
Nearsightedness occurs when the physical length of the eye is greater than the optical length. For this reason, it often develops in the rapidly growing school-aged child or teenager, and progresses during the growth years, requiring frequent changes in glasses or contact lenses. It usually stops progressing as a person finishes growing in his or her early twenties.
Nearsightedness affects males and females equally. Those with a family history of nearsightedness are more likely to develop it. Most eyes with nearsightedness are entirely healthy, but a small number of people with myopia develop a form of retinal degeneration.
Symptoms Return to top
Exams and Tests Return to top
A general eye examination, or standard ophthalmic exam may include:
Treatment Return to top
You can compensate for nearsightedness by wearing eyeglasses or contact lenses, which shift the focus point to the retina. There are several surgical procedures that reshape the cornea, shifting the focus point from in front of the retina to the retina.
Radial keratotomy is a surgical procedure that was popular in the recent past. Now it has been almost completely replaced by LASIK, in which an excimer laser is used to reshape the cornea.
Outlook (Prognosis) Return to top
Early diagnosis of nearsightedness is important, because a child can suffer socially and educationally by not being able to see well at a distance.
Possible Complications Return to top
When to Contact a Medical Professional Return to top
Call for an appointment with your ophthalmologist if your child shows these signs, which may indicate a vision problem:
Call for an appointment with your ophthalmologist if your child is having difficulties at school that may be caused by a vision problem.
Call for an appointment with your ophthalmologist if you or your child is nearsighted and experiences:
Prevention Return to top
There is no way to prevent nearsightedness. Reading and watching television do not cause nearsightedness. In the past, dilating eye drops were proposed as a treatment to slow the development of nearsightedness in children, but they have never been proved effective.
The use of glasses or contact lenses does not affect the normal progression of myopia -- they simply focus the light so the nearsighted person can see distant objects clearly.Update Date: 8/22/2008 Updated by: Paul B. Griggs, MD, Department of Ophthalmology, Virginia Mason Medical Center, Seattle, WA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.