Due to its safety and accuracy, Laser in situ keratomileusis (LASIK) has become the most popular procedure for the surgical management of myopia. During LASIK surgery, creation of a corneal flap is the first and the most critical step, as it influences the visual outcome. Since the introduction of microkeratomes to make the corneal flaps for LASIK surgery, the manufacturers introduced many modifications to produce more reliable and consistent flaps. Consequently, the femtosecond laser has been used in a wide range, and offered an alternative option for flap creation since the availability of the IntraLase™ (Abbott Medical Optics, Santa Ana, CA, USA) in 2001. There is an alteration in corneal biomechanics following different refractive procedures such as small-incision lenticule extraction (SMILE), femtosecond laser assisted Lasik and Lasik. Dry eye is a common complaint among patients who have undergone refractive surgeries, including Lasik, and femto-Lasik, and the occurrence of dry eye differs among these patients.
The purpose of this work was to assess and compare accuracy of the mechanical microkeratome and femtosecond Laser in the creation of flaps for Lasik and caps for SMILE using anterior segment optical coherence tomography (AS-OCT) and to detect corneal biomechanical changes after these surgeries.
In this study, we included 206 eyes of 103 patients (40 males, 63 females) with myopia or myopic astigmatism.
We divided the patients into 3 groups: -
Lasik Group: The Lasik group included 60 eyes of 30 patients received conventional LASIK surgery.
Femto-Lasik Group: The Femto-Lasik group included 76 eyes of 38 patients received a LASIK surgery with the flap created by the femtosecond laser.
SMILE Group: The SMILE group included 70 eyes of 35 patients got a SMILE surgery.
Our study included 206 eyes of 103 patients (40 males, 63 females) divided in three groups, Lasik group, Femtolasik group and SMILE group. No intraoperative or postoperative complication was noticed. No statistically significant differences were perceived between the three groups in relation to age, preoperative spherical equivalent, central corneal thickness, keratometric readings, CH, CRF and OSDI score (P>0.05).
In conclusion, our results showed that femtosecond laser (Carl Zeiss Meditec VisuMax femtosecond laser system) is more accurate and more predictable than mechanical microkeratomes. Corneal biomechanical changes are almost the same after the three procedures.