Relex Smile and its features for the correction of high degree myopia

Abstract

Purpose: to modify the calculated parameters of the refractive operation - extraction of the lenticle through small access (Smile), evaluate its safety and clinical effectiveness in correcting high-grade myopia. Material and methods. 34 patients (68 eyes) were operated by the modified Smile technology under local anesthesia. In all cases, patients had a high degree of myopia, in 37 % - in combination with astigmatism. Uncorrected visual acuity before surgery was on average 0.05 ± 0.11, Best corrected visual acuity was 0.94 ± 0.1, preoperative spherical refractive component -7.23 ± 0.75, cylindrical component -0.48 ± 0.59. During the surgery, in order to obtain the maximum possible refractive result according to the proposed method (patent No. 2018113414 of April 13, 2013), the standard parameters of the operation were changed: the thickness of the corneal flap was reduced to 100 μm, the neutral optical layer was 5 μm, the diameter of the optical zone depended on the residual thickness of the cornea, which should exceed 290 microns. The increase in corneal access was 15-20 degrees. Results. During the surgical intervention and in the postoperative period there were no complications. The next day after surgery, monocular uncorrected visual acuity in the distance in 73 % of patients was 0.8 and above, and in 41 % of cases it was equal to or exceeded 1.0. The spherical equivalent in the first day after the operation had a small hypermetropic shift, which was completely leveled by the year of observation. Conclusion. Using the proposed algorithm for calculating the refractive effect of the SMILE operation in high degree myopia allows obtaining a high refractive effect and avoiding possible complications.

Keywords

• smile
• femtosecond surgery
• smile
• high degree of myopia