Author: Dr Val Phua MBBS, MMed (Ophth), FRCOphth, FAMS
Photo by: Candice Picard
LASIK is the most popular choice for laser vision correction and many have undergone this procedure with deeply satisfying results. It almost seems like there was only this option available but in fact there are different techniques available and should be individualised to your needs.
Here is an overview of the most popular choices for laser vision correction available today.
Advanced Surface Ablation: PRK (Photorefractive Keratectomy), Transepithelial-PRK, Epi-LASIK, LASEK (Laser epithelial keratomileusis)
You may have heard some of these names being thrown about and for good reason. Advanced surface ablation is a safe and effective alternative to LASIK, however the recovery process is slightly more prolonged with some discomfort.
As with the LASIK procedure, the eye is numbed with eye drops to ensure comfort during the procedure. The thin layer of “skin” of the cornea is removed by different means, be it a gentle scraping, applying some alcohol or even the use of a laser. A corrective excimer laser is then applied to the surface of the cornea to reshape it and allow the eye to focus better. A bandage contact lens is then applied to help the eye heal.
The procedure itself is painless but once the numbing eye drops wear off, patients do experience discomfort, glare and halos in the early recovery phase. This feeling of discomfort takes about 5-7 days and vision slowly stabilises over 3 months. During this period, eye drops are given to prevent infection and minimise scarring and also to keep the eye comfortable.
The results from advanced surface ablation is comparable with LASIK in terms of best corrected vision and it has the benefit of not having a LASIK flap, however the healing process may vary in each individual resulting in some needing some enhancement with the passage of time.
LASIK (Laser In Situ Keratomileusis)/Bladeless LASIK/Femto-LASIK/All laser LASIK
LASIK is a highly dependable, time-tested means of reshaping the cornea to help the eye focus images onto the retina. The procedure itself has 2 main steps.
The first step is creating a thin LASIK flap. This is done after numbing eye drops are given to make the process painless. Traditionally, a fine blade (microkeratome) was used for this step, however with advances in femto-second laser technology, flap creation with the microkeratome has largely been superceded by the femto-second laser. The flap is then lifted and the eye prepared for the application of corrective laser.
Next, a corrective excimer laser is applied to reshape the cornea and allow the eye to focus better. This step is painless and typically takes seconds depending on the degree of correction needed. The flap is then replaced and a bandage contact lens applied.
Most patients who undergo LASIK will notice an improvement almost immediately and some with tight busy schedules can even return to work the next day. The recovery process for LASIK is quite different from advanced surface ablation with minimal discomfort and much faster stabilization of vision after the laser procedure. More than 98% of patients are satisfied with their vision after LASIK.
SMILE (Small Incision Lenticule Extraction)
SMILE is a recent addition to the armamentarium for laser vision correction. This procedure begins with numbing eye drops given and the eye held in position by a vacuum. It then involves using the femto-second laser to shape a thin disc of corneal tissue (lenticule) from the internal layers of the cornea. This part of the procedure is painless and is again done within seconds. This lenticule is then manually dissected and removed from a small side opening.
Unlike LASIK, there is no LASIK flap created in this procedure and the recovery is also fast and with minimal discomfort. Some also report a decreased incidence of dry eye after SMILE as compared with LASIK. However there remains a small risk of having to convert to the more time tested means of laser vision correction should there be suction loss during the procedure preventing an effective application of the femto-second laser to create the lenticule.
Implantable Collamer Lens (ICL)
Implantable collamer lens is an alternative that is rapidly gaining popularity in recent years. Unlike with laser vision correction which reshapes the cornea to help the eye focus better, in ICL, a special lens is inserted in front of the natural lens of the eye and behind the iris. It is able to correct myopia, hyperopia and astigmatism whilst leaving the cornea largely untouched. Many patients report immediate improvement of vision with minimal discomfort and some papers report patient satisfaction of 99%.
This procedure is however more invasive compared with laser vision correction and there remains a small risk of having an infection affecting the inner parts of the eye. There is also a risk of damaging the natural lens and causing a cataract during the insertion of this special lens.
Which option should you go for? There is no one size fits all answer. Rather, a personalised recommendation based on your specific needs should be made after taking a thorough ophthalmic history, examination and specialised tests which can highlight the suitability of each procedure for your eye. Journey along side your eye surgeon to discuss how best to achieve your vision goals.