There are several different types of laser eye surgery. The various terms used to describe each one can be confusing though. In this article we will discuss the difference between LASIK and LASEK, as well as SMILE and some of the reasons why one may be preferred to another.
LASIK is the most common form of laser eye surgery carried out in the world today. It’s estimated that there have been over 50 million procedures carried out worldwide. In many developed countries up to one in thirty of the general population of all ages have already had this procedure carried out.
LASIK involves creating a thin microscopic flap in the surface of the cornea and then re-shaping the cornea underneath this in order to change its power and accurately focus light. All of this is completely painless and takes less than 5 minutes for each eye.
The main advantages of LASIK are that both the laser eye surgery procedure and recovery are painless and that most patients experience fantastic vision after only a few hours meaning that a fast return to work is possible.
At Ophthalmic Consultants of London, all of our LASIK (and surface) procedures are wavefront treatments which means that the laser will be programmed to give you the best quality of vision possible.
LASIK stands for Laser-Assisted In-situ Keratomileusis. In order to better understand what this involves it’s helpful to break this down a little further:
LASEK stands for laser-assisted subepithelial keratectomy. It is one of a collection of procedures that we term advanced surface laser ablation.
Also included in this broad category are PRK which stands for photorefractive keratectomy, tran-PRK which is a no-touch PRK variant available at Ophthalmic Consultants of London and epi-LASEK which is a variant of LASEK.
All of these surface procedures involve reshaping the cornea without creating a flap. In order to do this the surface layer of cells on the cornea (the epithelium) are disrupted either manually or with a laser and must regrow. For this reason, although the procedure is painless, the recovery is painful for a few days and the vision is blurry for the first week, taking a few weeks to get to the 20/20 or 6/6 vision level or better.
We tend to only recommend a surface procedure when we feel that LASIK is not advisable; for example in thin or irregular corneas and around 10% of the laser vision correction procedures that we carry out are surface advanced surface laser ablation procedures. In higher prescriptions, we use the anti-scarring agent MMC (mitomycin C) to reduce the chance of haze following the procedure.
SMILE TM (Zeiss) stands for Small Incision Lenticule Extraction.
It is the newest form of laser eye surgery and involves using only one laser to create a lens within the cornea which is then dissected and removed. Some people are drawn to the fact that it does not require creating a flap in the cornea and that it is new.
However, because it is new means that certain safety features which are present in LASIK are not yet available with SMILE. Safety features for LASIK such as pupil tracking, centration control and astigmatism control do not exist with SMILE.
At Ophthalmic Consultants of London, we will have access to two more modern variants of SMILE; one is known as CLEAR which stands for Corneal Lenticule Extraction for Advanced Refraction and the other is currently in development with Schwind. If we see firm evidence that these lenticule extraction options are superior to LASIK then we will introduce them in to select patients.
However, at present it is our belief that LASIK remains the best option for the vast majority of patients.