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What is Lasik?
LASIK,
sometimes mistakenly called LASIX, is short for "laser-assisted
in situ keratomileusis." It is the most commonly performed
refractive surgery procedure -- partly because of the relative
lack of pain immediately afterward and partly because good
vision is usually achieved by the very next day, if not before.
An instrument called a microkeratome is used in LASIK eye
surgery to create a thin, circular flap in the cornea. The
surgeon folds the flap back out of the way, then removes some
corneal tissue underneath using an excimer laser. The laser
uses a cool ultraviolet light beam to precisely remove ("ablate")
very tiny bits of tissue from the cornea to reshape it. When
you reshape the cornea in the right way, it works better to
focus light into the eye and onto the retina, providing clearer
vision than before. The flap is then laid back in place, covering
the area where the corneal tissue was removed.
Both nearsighted and farsighted people can benefit from LASIK
surgery. With nearsighted people, the goal is to flatten the
too-steep cornea; with farsighted people, a steeper cornea
is desired. Also, excimer lasers can correct astigmatism,
by smoothing an irregular cornea into a more normal shape.
What is PRK?
In PRK (photorefractive keratectomy), an excimer laser removes
tissue directly from the surface of the cornea. Both LASIK
and PRK are an improvement over RK (radial keratotomy), a
non-laser procedure that involves making incisions in the
cornea in a radial pattern. The result is that the cornea
is flattened, thereby correcting nearsightedness. Drawbacks
to RK include pain, lengthy healing times, regression over
time, and scarring in some people. Since the incisions go
deeper into the cornea than the laser does, many surgeons
consider the surgery more invasive and therefore potentially
traumatic to the eye than PRK or LASIK. RK is rarely performed
now.
What is the difference between Lasik and PRK?
At LASIK VISION, most patients receive the LASIK (Laser in-situ
keratomileusis) corrective procedure. Depending on the health
and condition of your eye, PRK (Photorefractive keratectomy)
may be a better option. The same excimer laser is used in
both treatments.
In the LASIK procedure, before using the excimer laser, surgeons
gain access to the bed of the cornea by creating a hair-thin
corneal flap in the eye's outer membrane. A delicate, finely
tuned automated instrument called a microkeratome makes this
flap with exacting precision in a matter of seconds. After
lasering the cornea, the flap is replaced and the membrane
heals naturally.
In PRK, no corneal flap is created. The surface cells of the
cornea are gently polished away allowing the laser to reshape
the bed of the cornea. After the procedure, a protective lens
is placed over the eye for approximately five days while the
surface of the cornea heals. The lens is removed in a follow-up
visit.
What kind of Laser is used in ISH?
LASIK and PRK are performed with an excimer laser. This type
of laser produces a cool beam of light, which vaporizes the
corneal tissue allowing the surgeon to remove the imperfections
in the cornea. Ttthe Laser used in our hospital is Technolas
217-C LASIK 3 GENERATION and it is the most advanced laser.
Is Lasik safe?
The FDA recognizes LASIK and PRK as proven, safe, and effective.
There are risks associated with any surgical procedure, but
laser vision correction uses a cool beam of light that is
computer controlled. The surgeon turns the laser on and is
able to turn it off at any moment. With so many safeguards
in place, there is little room for error.
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