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  • 3 min read

With SMILE LASIK eye surgery being much in demand a lot of people have been asked about the difference between SMILE Lasik eye surgery Superlasik and of course the old warhorse PRK. In this post we are going to go into the actual steps of surgery in each the difference is that vantage and disadvantages or the pros and cons. We are also going to look at the technology needed and hence and hence the cost finally we will look at the long term outcomes and safety we can expect from each procedure.

SMILE being the latest procedure and technically the most advanced will be discussed first. Smile is an acronym for small incision lenticular extraction it has also been called RELEX that is refractive lenticular extraction. It uses a laser to fashion a disc of corneal tissue in the deeper planes of cornea. The shape of this tissue is dependent on the amount of myopic and astigmatism correction desired. What is interesting is though the actual prescription being treated might vary from let’s say minus two to minus ten the time required to do the procedure is the same at around 30 seconds. Currently only resume VisuMax laser from Carl Ziess is FDA approved to do this procedure in the US.

Are you a candidate for SMILE or PRK

SMILE: Cornea needs to be more than 475 microns in thickness. The residual bed, that is the amount of cornea remaining below the removed disc of tissue should be more than 250 microns (preferably 275 microns). The shape of cornea should satisfy the KISA index enumerated by our colleague Dr. Yaron Rabinowitz. If pentacam is available, cornea should clear the BAD algorithm. It goes without saying that the patients should have a stable refraction and be above 18 years of age. Also no active eye disease or uncontrolled systemic disease should be present.

SMILE OR PRK - which to choose
Disc of Corneal tissue removed during SMILE procedure

The results are fast and patients are in the 20/20 range in a few days to some weeks. There is no pain, nor discomfort while healing.

PRK or superlasik have now been around for 2 – 3 decades. They can be done in borderline corneas like 450 microns or a little abnormality in cornea shape. PRK can be done for teens if they are at risk for developing amblyopia or lazy eye.

The healing with PRK can be uncomfortable with some experiencing pain. The return to full vision takes weeks and in some cases months if there is development of cornea haze.

Which is Best for me – SMILE or PRK

So looking and considering all the factors we opine that when possible SMILE is a better choice for patients.