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Vision
problems resulting from refractive error (nearsightedness,
farsightedness, and astigmatism) have long been corrected
with eyeglasses or contact lenses. While these methods can
produce clear vision, eyeglasses and contact lenses are often
considered a hassle. There are two exciting ways in which
the excimer laser can surgically dramatically improve vision,
utilizing the same principles that allow eyeglasses and contact
lenses to produce clear vision: PRK, or Photorefractive Keratectomy,
and LASIK, or Laser Assisted In-Situ Keratomileusis.
Before PRK or LASIK, patients receive powerful numbing drops
so that they do not feel any pain during the procedure. In
PRK, the excimer laser allows the surgeon to reshape the surface
of the cornea using pulses of light emitted from the laser.
During LASIK, the surgeon uses a highly sophisticated computer
- assisted instrument called a microkeratome to gently create
a super-thin flap across the surface of the eye.
The powerful numbing drops administered prior to the procedure
ensure that patients do not feel any pain during the procedure.
The hinged flap is folded back, the excimer laser and microaeratome
is used to reshape the underlying tissue. Following laser
treatment, the flap is laid back in place. Both PRK and LASIK
are effective procedures for correcting refractive errors.
Although some surgeons prefer to perform PRK, and in some
cases PRK may be better suited for a particular patient, most
doctors favor LASIK now due to increased patient demand, faster
visual recovery, and fewer post-operative visits. The following
chart highlights some comparative information for the two
procedures.
|
PRK
|
LASIK
|
Procedure Time |
5 Minutes
|
5 Minutes
|
Procedure Used |
Excimer Laser
|
Excimer Laser
|
Bowman's Layer |
Removed
|
Left Intact
|
Post-Op Medication |
3 - 6 months
|
1 - 2 weeks
|
Post-Op Visits (1st
Year) |
8 - 10
|
5
|
Functional Visual Recovery |
3 - 5 days
|
12 - 24 hours
|
Risk |
Low Risk
|
Low Risk
|
Risk of Corneal Scarring |
1 - 3%
|
<1%
|
Risk of Infection |
<1%
|
<1%
|
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