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Prevention
in perspective
The best way to protect
vision is through good general health. A balanced diet
includes all the essential nutrients needed by the eyes
for each vision mechanism. Examination by a specialist
is critical to identify eye problems, and personal
hygiene and awareness of our own health and body is the
best way to keep our eyes healthy. Safety and correction
of vision defects complete the picture of a person who
is alive to the world they see around them.
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Computer
Vision Syndrome (CVS)
The fatigue and pain of
CVS shows up after long-term computer use leads to
physical stress including eyestrain. Not only with
computers. Videogames require extreme focus at a short
distant range which brings forth the same effects as
with CVS. Constant strain due to problems related to
lighting, posture, and the physical placement of screen,
keyboard, mouse and work material can cause CVS. The
syndrome is preventable. An additional critical
component of CVS discussed in this article is the
ultraviolet radiation emitted by computer screens. This
UV “noise” can be avoided by a filter placed
directly in front of the screen, by a low-UV monitor or
with appropriate eyewear (specially coated glasses or
contact lenses). Over 16 million North Americans have or
are at risk for CVS.
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Cataracts
As we age, the eye’s
lens may become cloudy and changes from crystal blue to
dull yellow. The cloudy lens is called a cataract. As
the cataract develop, vision becomes blurry and dim, as
less light passes into the eye. Cataracts may eventually
cause temporary vision loss. In the early stages,
low-vision aids can compensate for these problems.
Fortunately, the cloudy lens can be removed and replaced
by clear plastic lenses or other devices that restore
vision.
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Spots,
floaters and flashes
The spots, floaters and
flashes we sometimes see in our line of vision are part
of a natural process. While they may be bothersome at
times, in most cases these shadows and “light shows”
are not harmful. However, if there is a sudden increase
in the number of spots and floaters, if light flashes
continue or vision dims for too long, immediate medical
attention is needed.
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What are spots, floaters and flashes?
Spots, floaters
and flashes are all integral parts of the miracle of the inner
eye and its life cycle.
Spots and floaters are semi-transparent, thread-like strands,
specks or brilliant crystals that float inside the eye. When we
see spots and floaters, we may have the impression that foreign
objects are in front of our eyes, but find that the objects dart
away when we try to look at them directly.
Spots and floaters come in many shapes and sizes. They may
appear as tiny dots, round circles, long, thread-like strands,
cobwebs or fuzzy clouds. We usually notice them when looking at
a bright, blue sky or a blank, white wall. People of all ages
see spots and floaters. Nearsighted people and people with eye
injuries or inflammation see them more frequently. But in most
cases, even though they may be bothersome, spots and floaters
are harmless and fade away with time.
Flashes are experienced by most everyone in late adulthood. Some
flashes are caused by blood vessel spasms and can occur at any
age. In either case, they may appear as straight or jagged
vertical lightning streaks, shooting stars, fleeting white
pin-points or brilliant blasts of light.
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Shadows and lightshows inside our eyes
Spots and floaters are found in the tear layer
in front of the eye, in the iris (the colored part of our eye
that controls its exposure to light) and in the vitreous (the
white, gel-like substance that maintains the shape of the eye).
They are a normal part of the process of growth and degeneration
our eyes are destined to undergo.
In childhood and early adulthood, the spots and floaters most
people see are pieces of blood vessels that were left suspended
inside the vitreous of the eye when it was forming before birth.
They may also be specks of pigment on the muscle fibers attached
to the iris or particles caught in the tear layer in front of
the eye. These tiny objects drift freely in the eye and cross
our line of vision.
By the mid-forties, the vitreous starts to become more liquid.
As this change takes place, a combination of liquid and clumps
is present. The shadows cast by these crystal-like clumps are
floaters. At this point in life, eyesight may also become hazier
than in younger years.
By the time we reach our sixties and seventies, the vitreous
usually begins to separate from the retina (where we “see”),
at the back of the eye. At this point, a series of flashes may
be seen. The most fascinating thing about these flashes is that
they are all in our head! They are produced by the nerves in the
retina as the vitreous pulls away from it and rubs against it.
The brain is registering “light” because its light receptors
are being stimulated, but no light is actually present. Although
this process may be a little disturbing at first, it is
perfectly normal and should subside after a few weeks or months.
See “Protecting your eyesight” for details on how long
flashes should last.
Migraine flashes
Migraine flashes are brought about by blood vessel spasms in the
brain called migraines. Flashes appear as straight or jagged
streaks of lightning and give the impression of a heat wave.
Although they may be bothersome, migraine flashes are usually
temporary occurrences. They may or may not occur just before a
migraine headache is about to begin.
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Treatment and correction of spots, floaters
and flashes
If your floaters or flashes come from a retinal
tear or detachment, laser surgery may be performed to repair
damage as soon as possible. However, most spots, floaters and
flashes are simply a fact of life, and there is no safe,
reliable treatment to control or eliminate them.
In very rare cases, when vision is almost entirely clouded by
spots and floaters, vitrectomies may be performed. In this
surgical procedure, the vitreous of the eye is replaced with a
saline solution to improve clarity of vision. However, this
treatment is not usually recommended because it may cause
blindness.
When everyday spots and floaters are bothering you, try looking
up and down and from side to side. As you move your eyes, the
vitreous fluid will swirl around, and floaters will often move
out of your line of vision.
Until medical science comes up with other, safer solutions, it
is best to let the eye’s natural elimination processes take
care of stray spots and floaters.
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Protecting your eyesight
On rare occasion during the natural process of
the separation of the vitreous from the retina, blood vessels in
the eye may leak, and the retina may be torn or may detach from
the inner lining of the eye. Damage to the retina may also occur
due to injury, disease, inflammation of the eye, macular
degeneration or other health conditions.
When the retina is detached or seriously damaged, a rush of
sparks or lightning flashes and showers of floaters may be seen,
and part of the field of vision may become dim or black, as if a
curtain has been partially drawn. No matter what the cause, if a
sudden increase in spots, floaters and flashes lasts more than
20 to 40 minutes, it should be considered an emergency, and
immediate medical attention sought. Left untreated, retinal
damage or detachment may result in permanent loss of vision.
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From specks to spectacles
Most people are naturally curious about the
phenomenon of spots and floaters. Indeed, many of the secrets of
the eye were actually revealed because of the natural curiosity
of a Dutch physician named Frans Cornelis Donders. He wondered
about the funny specks he and his patients saw before their eyes
and where they might be coming from.
In 1847, Donders excitedly began a study on those specks. His
fascination with the miracles of the eye was to lead him further
and further into the field of ophthalmology (the science of the
eye). Through his research, he solved many of the mysteries
behind spots and floaters. In the same study, he formulated
Donders’ law, a groundbreaking theory on the rotation of the
eye around the line of sight.
As he continued his research, Donders went on to improve
approaches to the diagnosis, surgery and treatment of eye
defects. He discovered the physical causes of nearsightedness,
farsightedness and astigmatism, and greatly influenced the
design of eyewear. Today, Frans Cornelis Donders is remembered
as one of the greatest minds in ophthalmology. And it all
started with a few specks!
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Red
eyes
Did you know that red eyes can be allergic, viral, bacterial,
toxic, or just plain dryness.
Optometrists like Drs. Belanger and Marra are experts in
determining the cause and treatment plan. The most common causes are allergic and/or dryness. We know have some extremely effective new anti-allergy
drops by prescription with the proper diagnosis. Many tear
regulation problems can be treated with punctual occlusion which
plugs the drainage hole of the eye and allows tears to pool.
We can demonstrate the effectiveness with a temporary
plug before proceeding with a long lasting solution. See your
optometrists for diagnosis and treatment of red eyes.
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Your
child's first eye exam
Your child should have his or her first vision examination by no
later than three or four years. of course, children with any signs of
eye problems should be examined immediately, regardless of age. Modern technology makes It
possible for a Doctor of Optometry to examine a child who is too young to read, talk or
answer questions. it is also Important to remember that an
annual school vision screening DOES NOT constitute a thorough
visual exam.
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