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In the United
States, macular degeneration in older
people is the leading cause of sight
impairment that is perceived as a loss of
sight for reading and close-up work.
Macular degeneration is the deterioration
of the central part of the retina (macula)
where the central vision is focused.
The retina is an extremely thin layer of
nerve tissue that lines the inside back of
the eye, not unlike the way film is lined
against the back of a camera.
The retina's function is to receive the
focused light images and send visual
messages to the brain. The brain
interprets those messages as vision. The
macula is that part of the central retina
that is used for central vision: reading
and seeing things in extremely fine
detail.
In some people 60 years of age and older,
certain areas of degeneration and scar
tissue start to develop in the macula.
With aging, trauma or medical problems,
the macula can further degenerate and
cause various central vision symptoms. The
most common complaint is that the eyes
tire easily with close work, and words
blur after reading for a short period of
time. Sometimes, distortion of objects and
letters is the main problem. With further
degeneration, decreased central vision
occurs.
The cause of this condition is not known.
Aging and "hardening of the arteries" may
contribute to this degeneration. It
progresses at different rates in different
people, and we cannot always predict the
outcome.
We do know that at this time, no
medicines, surgery or diet will reverse it
or improve it. The most common form of
macular degeneration can be treated by
laser surgery, but this cannot restore
vision that has already been lost.
Changing eye glasses does not help,
because the purpose of glasses is to focus
light on the macula, which is damaged. It
is like having old film in your camera. If
the film is no longer perfect, even the
most expensive camera lens will not give
you a sharp picture.
Recent scientific studies suggest,
however, that antioxidants, such as
vitamin C, vitamin E, beta carotene and
also zinc may help prevent macular
degeneration due to aging.
And it is proven that ultraviolet sunlight
speeds up macular degeneration. To protect
your vision, sunglasses with 100 percent
ultraviolet protection should be worn 100
percent of the time you are outdoors.
Some good news is that using your eyes
does not make macular degeneration worse.
Eyes can be used for long periods, and if
they tire, they can be rested a few
minutes and then used again.
And two things can help: One is having
good light, and another is using a hand
magnifying glass to read small print.
People with loss of central vision never
go blind. They may lose sharp, central
vision, but they will always keep the side
vision surrounding this blurred central
spot. Most people will also continue to
read and drive, even though they no longer
have 20/20 vision.
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