Comparing lasik and PRK treatments for myopia correction
Within the past two decades,
surgical methods have been developed to permanently correct myopia (short- or nearsightedness).
The two most common procedures are photorefractive keratectomy (PRK) and lasik.
In a review that compares these two
vision-correction surgeries, Dr. Alex J. Shortt of the Institute of Ophthalmology
and Dr. Bruce D.S. Allan of Moorfields Eye Hospital, both in London, found that,
although PRK was approved by the FDA first, lasik has become more popular. Both
procedures use a laser to correct myopia by altering the cornea, but PRK does this
by removing small layers of the tissue, while lasik opens a flap of the cornea and
removes excess tissue underneath.
The authors looked at six trials that
yielded information on surgeries in a total of 417 eyes, 201 of which received PRK
and 216, lasik. Their analysis revealed that less pain is experienced during PRK
than with lasik, that recovery from lasik is faster and less painful than recovery
from PRK, and that postsurgery vision acuity and accuracy are comparable for both
Both surgeries showed some minor negative
effects, however. PRK resulted in a slight loss in best spectacle-corrected visual
acuity as well as occasional visual side effects such as haze and glare. Lasik surgery
occasionally had complications related to the corneal flap, though these problems
had mostly mild or negligible permanent effects. The authors also noted that lasik
may be safer than PRK but that not enough data was available to make a definitive
conclusion. (The Cochrane Database of Systematic Reviews, April 2006, Issue
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