There are several reasons to choose Epi-LASIK over any procedure that involves cutting a "flap" in the cornea. The two procedures in which the cornea is cut are 1) LASIK in which an exquisitely sharp stainless steel blade is used to cut the cornea and 2) “bladeless” or “Intralase” in which a laser is used to cut the cornea.
Both cutting procedures will irretrievably weaken the structure of the cornea just by the act of cutting the flap, because in the healing process, the edges of the flap typically seal overnite, but research published in 2011 proves that the inner face of the flap never heals completely to the underlying bed of the cornea. It is doubtful that this partial healing will ever permit the cornea to regain its original structural integrity.
In both LASIK and Epi-LASIK, the second part of the procedure – laser reshaping of the cornea to create the change in focusing of light rays on the retina – which removes a small amount of the tissue from the deeper layers of the cornea will weaken it slightly, but this amount of tissue removal is usually so slight that its effect on corneal strength can barely be detected.
Epi-LASIK is the modern version of PRK (which is the Laser Vision Correction procedure initially approved by the FDA in 1995). Epi-LASIK does not involve any cutting of the cornea and therefore does not diminish the structural integrity of the cornea.
Corneal weakening in LASIK is only one reason that Epi-LASIK is a safer procedure than LASIK. Other reasons are: 1) less dry eye induced, 2) lower potential for complications in the absence of a flap, 3) better potential quality of visual results because perfect healing of a flap is a non-issue.
To my mind, the only disadvantage of Epi-LASIK is a slightly longer recovery period, three to six days versus one day. During those three days, limitations are minimal. I instruct my patients to avoid rubbing the eyes, avoid getting tap or shower water in the eyes and to avoid tobacco smoke which makes dryness worse.
PRK/Epi-LASIK Frequently Asked Questions
Read a series of questions and answers to help you understand the value of Epi-LASIK.