Photo-Refractive Keratectomy, PRK is another method of surgically
reshaping the cornea using the excimer laser. The difference between
LASIK and PRK is that for PRK, the corneal flap is not created.
That is, the outer layer of the cornea remains in place and the
laser removes tissue directly from this outer layer. During LASIK
, a part of the cornea is peeled back so that the laser removes
tissue from the inner corneal layers. PRK is used for low to moderate
amounts of nearsightedness.
Just as in LASIK, the laser treatment requires less than a minute.
But unlike LASIK, the healing period time is longer. The correction
for nearsightedness, farsightedness and astigmatism is the same
as in LASIK. The corneal curvature is changed so that the visual
images are properly focused on the back of the eye.
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