MYOPIA
- NEARSIGHTEDNESS
Nearsightedness (myopia) is a very common vision condition that
affects nearly 30 percent of the U.S. population. Some evidence
supports the theory that nearsightedness is hereditary. There is
also growing evidence that nearsightedness may be caused by the
stress of too much close vision work. It normally first occurs in
school age children. Since the eye continues to grow during childhood,
nearsightedness generally develops before age 20.
An
individual that has myopia has trouble seeing clearly at a distance.
With myopia, the center of the cornea is thinned, like cutting the
hole in a donut. The thinned cornea corrects the blurred vision
from myopia, weakening the near sighted (too strong) eye. The rays
(of light) entering the eye are bent too much, and focus ahead of
the retina, which is the normal focusing point.
After
compressing, the rays spread out again, becoming scattered by the
time they reach the retina, thus causing blurry vision.
Symptons
of myopia include:
• blurred vision of distant objects
• squinting
• eyestrain
• headaches
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Effects
of the condition
Myopia
causes light rays to focus on the front of the retina and
so close objects are seen clearly whilst distant objects appear
blurred.
Near
vision can deteriorate to a level where even very close to
the face become hard to focus.
myopic
vision
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There
is a slight danger of sight loss since the deformation of the eye
creates stress on the retina which can become damaged or detached
and can also provoke other changes. This is especially the case in
high myopia.