About LASIK Surgery
LASIK
Surgery Many
people love the idea of getting rid of their glasses and
contacts, but they cringe at the thought of having a procedure
performed on their eyes. We’re hoping that we can help people
overcome their fears by providing accurate and helpful
information about LASIK and other refractive procedures. With
time tested technology and fine-tuned surgical skill, this
procedure is one of the safest, most effective eye treatments
available. And we believe the benefits far outweigh the
risks.
What is LASIK surgery
exactly? It’s
the use of a laser beam to modify the shape of your cornea such
that your vision will improve. So let’s look at how our vision
works, why it might be less than perfect, and how LASIK surgery
changes it.
How does our vision
work? It all
depends on light. Our eyes are balls, made such that they
receive light rays on the front side and bend them (refract
them) to focus on the inside back surface of the eye (the
retina). It’s very like the way a traditional camera directs
light onto a film inside it.
So the object from which the light
rays have been reflected to our eyeballs shows up as a little
image on the retina, a tiny upside down picture of itself.
There’s a large nerve at the back of each eye called the optic
nerve which then transmits this image information to our brain
and our brain understands and interprets it and tells us, “That
there is a tree!”
So why, for some of us, does that
tree look blurry or indistinct or distorted? Because the image
information sent by the optic nerve was deficient in some way
so the brain didn’t receive enough information to interpret
correctly, and maybe it told us, “That there is a telegraph
pole!”
That happens when the cornea isn’t
perfectly round and the light rays are not refracted correctly,
so they don’t form a perfect image. This is where LASIK surgery
enters the picture, so to speak.
Kinds of laser eye
surgery LASIK
stands for Laser-Assisted in-situ Keratomileusis. There are 3
main varieties of LASIK surgery, only one of which is correctly
called “LASIK surgery”, and it’s principally used for people
who are very shortsighted or very longsighted. The other kinds
are:
PRK
(Photorefractive Keratectomy), which was the original kind and
is still sometimes used. It involves gently scraping some
surface cells off the cornea and then using a laser beam to
re-shape it.
More about PRK
E-LASIK, or Lasek
(Laser Epithelial Keratomileusis), which is used for people
with mild to moderate short-sightedness, whose corneas are too
thin and delicate for regular LASIK surgery. A finer blade is
used to cut a tiny flap from the epithelium of the cornea, but
before it’s lifted, an alcohol solution loosens the edges. Then
the LASIK surgery re-shapes the cornea and the flap is
replaced.
More about Lasek with an
"e"
Epi-LASIK,
(Epithelial Laser In-Situ Keratomileusis), which, like e-LASIK,
is for those whose corneas are too too thin and delicate for
regular LASIK surgery. Instead of cutting the tiny flap and
using alcohol to loosen it, the flap is gently separated by a
specially designed instrument; then the laser does its work as
in the other methods.
More about Epi-LASIK
What is a
laser?
“Laser” is a word now, but
originally it was an acronym for light amplification by
stimulated emission of radiation. It’s a kind of light beam
that we specifically create for a purpose, and can be
ultraviolet, infrared, or within our vision range. There are
many kinds of lasers, named according to how they’re created:
solid-state lasers, gas lasers, semiconductor lasers and
excimer lasers, for example.
All laser beams are a single color
(as opposed to regular white light, which contains all colors),
and they’re directional, meaning that the photons (light
particles) contained in the beam are in lockstep, so the beam
is highly focused and concentrated. If you’ve ever seen a laser
pointer used in a classroom, for instance, you’ll get the
picture.
Which lasers does LASIK
surgery use?
LASIK surgery uses ultraviolet
beams called excimer lasers.
Traditional LASIK
surgery In
traditional LASIK surgery, a round, thin flap is cut from the
cornea’s surface in a way that leaves part of it still
connected. It’s gently folded back to expose the stroma, the
next level of tissue. Then an excimer laser is directed
precisely onto the stroma to vaporize tiny areas, thus removing
irregularities that are causing defective vision. The little
flap is then replaced and the eye heals itself in a day or
two.
All Laser
LASIK Many
LASIK surgeons use the IntraLase laser to create the LASIK
flap. Click here to find out more about IntraLasik.
Wavefront LASIK
Surgery The
most recent step forward in LASIK surgery was in 2002, when the
FDA approved a procedure called Wavefront LASIK Surgery. It has
so far approved 3 such systems.
In Wavefront LASIK Surgery -
sometimes called "Custom LASIK" - a computerized device beams a
light at each eye, which lands on the retina. Then it rebounds
to a sensor which tracks the irregularities of the front of the
light wave as it comes from the eye. Using this information,
the computer program makes a 3-D map of the precise shape of
the person’s cornea.
The LASIK surgeon translates this
map of wavefront data into a mathematical formula on the
computer and from that, programs corrections into the excimer
laser.
The laser is thus guided in
vaporizing tiny amounts of eye tissue to reshape the cornea,
and in this way, the eye’s refractive errors are
corrected.
Advantages of Wavefront
LASIK Surgery This type of LASIK surgery can correct what’s
called higher order aberrations (haloes, glare and blurry
images), as well as the lower order aberrations (astigmatism,
short-sightedness and long-sightedness).
The results are also a little more
predictable than those of traditional LASIK surgery. And
further, studies done so far suggest that over 90% of people
who have Wavefront LASIK Surgery achieve 20/20 vision, as
compared with less than 80% of people who have traditional
LASIK surgery.
Is Wavefront LASIK Surgery
best for me? That’s a question to ask your LASIK surgeon,
because the answer depends on many factors. For example, if
your eyes are particularly dry or your corneas too thin, you
may do better with traditional LASIK surgery. Other eye
conditions are relevant too, and the degree and type of your
visual irregularities.
Choosing a LASIK
surgeon Although there are many LASIK surgeons these
days, they aren’t all equally desirable. Before choosing one,
interview several and ask lots of questions. And before asking
the questions, know what answers you should get!
That means doing research for
yourself, because your eyes are not replaceable and you’ll want
to trust their well-being only to a properly trained,
certified, professional and trustworthy LASIK surgeon. And
choose a LASIK Surgeon who you feel personally comfortable
with, because no surgery, LASIK or otherwise, is guaranteed to
proceed perfectly. If there are any post-op complications, you
want to be confident your LASIK surgeon will listen to you,
answer your questions, and follow-up
conscientiously
Lasik Directory, 10/28/2008
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