What is short-sightedness (myopia)?

"Myopia or shortsightedness is a form of refractive error. It occurs when the power of the eye is too strong or the eyeball grows too long. In shortsightedness distance vision is blurred and near vision is usually clear (although may be blurred if the myopia is very high or astigmatism or presbyopia is also present). Often myopia begins in childhood or the teenage years and usually increases up until the early 20s, although it may stop earlier or later."
"People with high myopia are more prone to retinal problems such as retinal tears and retinal detachments, so they should have more frequent eye examinations than the average person."
"The blurred vision caused by myopia can be corrected using spectacles, contact lenses and sometimes refractive surgery."

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