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.
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.