Possibilities of using low-energy laser parameters with SMILE

    Purpose. To study the influence of various laser energy parameters on the refractive result and the terms of visual rehabilitation of patients in the correction of myopia using SMILE.

    Material and methods. 120 patients (120 eyes) with moderate myopia, in some cases with myopic astigmatism, operated on using SMILE. Divided into 4 groups depending on the energy level applied during the operation (130–160 nJ). Patients underwent complete ophthalmic examinations preoperatively and over 3 months postoperatively.

    Results. A statistically significant increase in UCVA was obtained in the group with an energy of 130 nJ from 0,09±0,05 to 1,02±0,06 on the first day after surgery and up to 1,17±0,06 after 1 week. The use of low laser energies didn’t lead to an increase in HOAs.

    The black spots & areas: 1 – 3,33% (4), 2 – 3,33% (4), 3 – 4,17% (5), 4 – 8,33% (10 eyes). The largest number of cases of OBL formation was noted in group 1 (160 nJ) – 40% (12), 2 – 26% (8), 3 – 17% (5), 4 – 7% (2 eyes). The actual residual stromal thickness (OCT) after SMILE was 78,32%±0,02, 78,76%±0,02, 78,81%±0,02, and 79,23%±0,02 in each of groups in accordance with the applied energy (no significant differences).

    Conclusion. The use of low laser energies in SMILE contributes to a rapid recovery of vision in the early postoperative period with less energy impact on the corneal tissue, which allows to obtain a better surface without OBL, rapid healing and restoration of corneal thickness after correction.

    Keywords: SMILE, myopia, lower laser energy levels of femtosecond laser, OBL, Black spots & Areas.