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 Vision is
an amazing gift of the nature especially appreciated by those who have
significant physical defects in this regard. Through vision a human being
perceives more than a half of the entire information from the surrounding world.
Unfortunately, the increasing workload to eyes so typical in our world brings
to various eye pathologies. It usually refers refraction ability of eyes, the
ability to change or accommodate optical system of eyes when visualizing close
or remote objects.
Thus, dry statistical
data confirm that over 30 % of the world population wears glasses or contact
lenses. M.S. Norbekov, the well-known author of the variety of popular books on
the methodic of vision correction, called the lenses «crutches for eyes».
Recently it
was possible to correct vision only by wearing glasses or lens, while it was
used forever. However, by the late ХХ century the core point of the situation
has not changed.
The
attempts to correct the eye optical system date back the pre-war period when of
the surgeons-ophthalmologists from Japan suggested a surgical operation in 1939
by means of applying special insections. And only 33 years after the Russian
ophthalmologist Svyatoslav Fyodorov managed to significantly improve the
technology of this surgery. Nevertheless, before and after the improvement
there was still the risk of aglia and various kinds of micro traumas and
complications. A new phase in evolution of optical operational technologies was
the idea of laser eye surgery proposed still in 1949 by the Colombian native, Ch.
Barracauer. This idea was implemented in practice only thirty five years after
in Germany when the laser correction of vision was performed in 1985. Since that
time the advantages of eye correction by laser technology are properly
appreciated by all famous ophthalmologic clinics; yet, the said technology
became an integral part of the modern practical ophthalmology.
So, what is
the heart of the laser eye correction technique? To understand it in detail, we
need to remember an eye structure. Every eye constitutes perceiving and image
conductive parts. The perceiving part is the retina whereupon the image is
focused. The leading function is performed by two optical elements in the
conductive part of eyes, a cornea and crystalline lens which affect the focus
of image. This focus should be located on the retina, as a rule, and in this
case objects, perceiving by the eye, will have clear contours. And the image is
blurred provided that the focus occurred in front of or after the retina. And
in this case we consider nearsightedness or long sight also there is refraction
pathology when the image is distorted. It happens with astigmatism cases.
With laser
vision correction the «profile» of cornea is changed. During this procedure the
laser ray does not burn the cornea, as many think, and does not penetrated
farer of cornea borders, that is why troubles and disturbs on possible trauma
of eye structures are quite vain. Laser removes the cornea parts that present
the optical obstacle for precise focusing of image onto the eye retina. For
instance, central areas of cornea layer are «smoothed» with nearsightedness and
with long sight - peripheral areas of cornea layer. Prior to the procedure of
the laser correction the patient is recommended to visit a specialist at the
proper clinics who studies an opportunity of surgical operation, makes all
necessary testing and determines the program of laser impact.
There are
several kinds of laser correction techniques. One of them proposes careful
insection of the very fine layer of the cornea (but it is not removed fully), that
is slightly turned backward for easy access to internal layers of the cornea. In
other cases the operation is performed directly on the superficial layers of
the cornea.
Whatever
technique is chosen by the doctor, the operation provides 100% vision
correction in the short terms. And within first days after the surgery the
patient is able to come back to his normal life style, but with new and valid
vision.
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