SMILE vs LASIK
SMILE is the newest laser vision correction technology. It is suitable for corrections of refraction errors such as miopy, long sightedness and astigmatism.
SMILE means Small Incision Lenticule Extraction, which explains the essence of this new revolutionary technique, and in the same time this combination of letters is very symbolic: the smile on our patients face just a few weeks after operation, finally being able to get rid of their glasses! SMILE surgery is the logical continuation, the advanced successor of the traditional laser vision correction technology known as LASIK.
LASIK is a traditional laser surgery technique for refraction errors correction, and has been used worldwide since its invention in the middle of 1980-s.
LASIK, or "laser-assisted in situ keratomileusis," is the most commonly performed laser eye surgery to treat myopia (nearsightedness), hyperopia (farsightedness) and astigmatism. Like other types of refractive surgery, the LASIK procedure reshapes the cornea, to enable light entering the eye to be properly focused onto the retina for clearer vision. Numbing eye drops are used. The eyelids are held open so that there is no interference with the laser. The ophthalmologist manually, or by using the Eximer laser, creates an ultrathin flap (20 mm long) on the front of the eye. The flap is gently lifted and the preprogrammed laser then reshapes the inner cornea to refocus the eye. In many cases it is necessary to use two lasers. One for the section, and another for correction itself. The flap is repositioned and holds itself in place, healing naturally without the need for any stitches. The laser pulses last on average between 30 and 60 seconds. In all, LASIK takes about 20 minutes to do both eyes.
The flap remains the weak link in LASIK; because it can easily be lifted, misplaced or traumatised, it consequently compromises corneal stability for decades (probably for life) after treatment. Another side effect of LASIK is the risk of the appearance of the dry eye syndrome, because of the 20 mm cut on the surface of cornea that can cause changes in the nerve ends and natural secretion of meibomian glands.
Despite of the side effects mentioned above, LASIK surgery is in many instances the operation of choice. In part because of its time proven high reliability, and also comparatively low criteria, presented to the state of the patients eyes (first of all, cornea) to their age, to the presence of the associated diseases and degree of the refraction error (quantity of dioptrics, which are necessary to correct).
SMILE – is a new less invasive surgical technology that made a revolutionary change in the modern ophthalmology and laser vision correction surgery.
SMILE was developed in the beginning of 2000, and immediately gained enormous popularity in the entire world. During the last 15 years opthalmologists carried out hundreds of thousands of successful operations. Statistics shows the high degree of patients satisfaction, for those who went through the SMILE correction, and this fact guarantees reliability and quality of this operation. Two distinctive special features of SMILE surgery – opportunity to correct vision through the minimum section of cornea, with no need for creating the corneal flap, and also the use of the only one femtosecund VisuMax laser both for the section and for correction itself. In comparison: the size of section during the operation of LASIK – 20mm, and SMILE -2-4 mm). The major advantage of SMILE is that there is no flap cutting, which may minimize the induction of spherical aberration and eliminates the incidence of striae. Without the potential for spherical aberration, patients treated using the smile technique are more likely to achieve better quality of vision than patients treated with an Excimer laser. This is especially true for those with high myopia. SMILE may also offer better biomechanical stability than procedures employing flap creation, along with less postoperative discomfort and a lower incidence of dry eye. With no potential for flap displacement, even after trauma, smile is the best procedure for those who are involved in contact sports. Unlike Excimer laser-based procedures, SMILE uses a solid-state laser, and therefore, there is no need for consumable gases or tight environmental humidity control. The VisuMax is a silent, soft, and gentle laser. It does not produce a smell, there is no vision blackout during the procedure, and the cornea is not forced into a nonphysiological planar shape. As a result, deformation and artifacts can be avoided in the cutting results as well as unnecessarily high intraocular pressure.
In spite of everything said, and also the entire revolutionary character and proved reliability of SMILE laser correction, it is important to remember that the choice of the operation (SMILE or LASIK) that suites different people is a very individual question and the final solution always depends exclusively on the eye test results and analysis of each patients individual situation.
Before the operation the patient goes through an extensive eye test, performed by our experienced ophthalmic nurses on the ultramodern OCT tomographs and other optimethric devices.
- The examination of visual acuity
- The examination of the diameter of pupil and cornea
- Corneal of pachymetry
- Corneal topography
- Examination of the vision field
- Intraocular pressure
- Examination of the eye fundus
The checkup examinations are usually performed 1 month and 12 months after the surgery, but there may be individual variations.
Healing after the laser surgery is quite quick.
After the laser eye surgery procedure, you may feel tired and dizzy, especially if you have had some form of sedative to help you relax. It is likely that you will not feel much pain in your eye until the local anaesthetic eye drops have worn off.
For the first 8 to 10 hours you will be unable to see much out of the treated eye, everything will seem blurry or cloudy. After this period, your vision will begin to return back to normal. Once the anaesthetic has worn off, you will probably begin to feel a dull pain in your eye that may make you want to itch or rub it. It is important to try and resist this urge as much as possible, as it can damage your eye before it has the chance to heal. Alongside this, it is likely that you may have some degree of light sensitivity, as well as the feeling of having something in your eye. To help your eye heal, you will usually be given some eye drops to put in at certain times. These drops are used to lubricate the eye, as well as prevent it from becoming infected or swelling up. During the recovery period, it is recommended that you wear no makeup on or around the eye as this can cause irritation. There is also no swimming, training or lifting of heavy things for up to eight weeks following the procedure. You will be allowed back to your normal routine after a few days (check this with your surgeon).
Over the following few weeks after surgery, it is likely that your vision will begin to return to normal, however you may still experience some symptoms, such as light sensitivity, starbursts or halo's and glare. These problems usually disappear after approximately 2-4 weeks and you should be symptom free after the first month, leaving you to enjoy your corrected vision.
On the day of the operation the patient is met by our nurses, and after papers are signed they accompany him into the surgery room. The operation is painless and takes no longer than 20 minutes. The patient can go home right after the procedure, with the assistance of a friend or a family member. Driving a car on the operation day is strictly forbidden. In some cases our clinic provides a taxi ride home without additional charge.
The operation of SMILE is performed under topical anesthesia. The patient is located on the mobile bed under the laser. The spherical patient interface of the contact glass is designed to provide the best fit with the anatomical shape of the cornea, minimizing tissue compression and ocular irritation. After the contact glass is attached, the system self-calibrates. Keratometry data can then be entered to account for the difference between the relaxed cornea and the contact glass curvature. This calculation allows the system to determine the ratio between the intended clinical treatment and the cap’s diameter on the relaxed eye, as well as the incisional diameterwhen cutting the eye coupled to the contact glass. With the patient fixating on a flashing green light, the surgeon manually repositions the bed so that the cornea meets with the contact glass. The patient will then notice a flashing fixation target in clear focus. This target uses the manifest refraction of each individual eye to adjust the target’s visibility. The patient’s bed is raised vertically, and the surgeon observes the alignment of the contact glass application through the operating microscope and the side screen during the entire docking process. The cornea slightly applanates and centers as the surgeon aims for the corneal vertex, and suction is applied to immobilize the globe. The increase in intraocular pressure with the VisuMax is low enough that the patient can see throughout the procedure.
If the refractive error deviates more than 0.50D from the target refraction, we will perform the necessary new surgery free of charge two years from the initial surgery.