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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?
We use the Wavelight
Allegretto Excimer Laser instrument which is a 4th
generation laser with advanced properties.
It functions with 0.95 mm.
Diameter mobile laser beam. The speed is rather high
(200 Hz.) as compared to other lasers. This high speed
creates a more uniform action surface.
Moreover, it possesses a
250 Hz. eye tracker system. This property prevents
deviations of hitting other areas even if the patient
moves eyes doiring treatment.
Besides, the ablity to
adjust the eyes rotation on the center axis (cyclotorsion)
with Kappa angle (angle between eyeball center axis and
vision axis) enables the instrument to target only the
treatment area.
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. |
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.