Excimer Laser Techniques
Today, there are many types of laser treatments. These can be categorized into 3 main groups
GROUP 1: SUPERFICIAL METHODS: It is the method of giving new shape to the superficial stroma layer that is exposed after mechanical, alcohol or laser removal of the top layer called epithelium without making an incision in the cornea. It is the oldest methods and is divided into 3. These are PRK, LASEK and the new version of the old method is NON TOUCH LASER. These methods are preferred today in patients who cannot use flap methods due to thin corneal thickness or dry eye. In PRK, the upper epithelial layer is peeled off and left to heal on its own after the laser. In LASEK, the epithelial layer is denatured and removed with alcohol and after the laser is applied, this denatured epithelium is covered back over the treatment area. In NON TOUCH LASER, the superficial epithelium is removed by laser, it is not a new method, it is a new version of the old method. Since there is no incision in superficial treatments, the temporary dry eye that occurs in the first 3-6 months in flap methods does not occur in these methods. However, it is not preferred for high numbers since there is a risk of spotty healing called haze when applied on numbers 4.5- 5.
2 GROUP: FLAP METHODS: These are laser treatment methods based on the principle of removing a thin flap-shaped layer called flap in the layer we call the anterior stroma just below the epithelium in the cornea and giving new shape to the deeper layer with laser. In these methods, a flap that holds one edge of the cornea is removed and the laser is applied to the deep layer called the stroma. If this flap is removed with a knife, we call this the LASIK method. The LASIK method is now abandoned in the world and is a risky method. If the flap is removed not with a knife but with a femtosecond laser, we call this method INTRALASIK - ILASIK, which is still the last method in the world and is a very safe method. It is very important for patients to be sure that a knife will not be used when the laser will be used and that the incision will be made with a femtosecond laser.
GROUP 3: SMALL CUT LENTICLE SURGERY (SMILE LASER): It is a new generation laser technology discovered in recent years. Unlike traditional lasers, there is no new shaping of the cornea by vaporizing tissue with the laser. It is based on the principle that a part called lenticule is formed in the anterior stroma layer by the laser device to correct the refractive error in the patient and the surgeon removes this lenticule from the cornea with special techniques through small incisions. In the near future, in hyperopia, where the success of excimer laser is limited, there are ongoing studies on treatments such as placing lenticules removed from myopes into pockets created in hyperopic corneas with smile. In keratoconus patients, lenticule transplantation with smile and studies to thicken and support thin corneas are also promising.
