Abstract
Purpose :
To describe the surgical results with the SMILE technique in terms of efficacy, precision, safety, contrast sensitivity and optical aberrations in patients with myopia and/or high astigmatism.
Methods :
Desing: Prospective, observational, descriptive, comparative, cross-sectional, non-probabilistic study.
Patients with refractive defects that were in a range of -6.00 D to -10.00 D of sphere and/or astigmatism of -2.50 D to -4.50 D were included, where the spherical equivalent of -10.00 D was not exceeded marking the axis at 0 and 180 degrees to reduce as much as possible the ocular cyclotorsion movement during the procedure. The surgical results were analyzed in terms of efficacy, precision and safety, as well as contrast sensitivity, optical aberrations and tomographic maps of anterior and posterior elevation in the preoperative period and 3 months after surgery. Initial and final visual acuity was compared and determined by Snellen chart at 20 feet, converting the result to Logarithm of the Minimum Angle of Resolution (LogMAR).
Results :
A total of 11 patients (22 eyes) were included, determining an efficacy of 100% (visual acuity >0.10 LogMAR, p<0.0001), precision of 63% (spherical equivalent 0.50 D, p 0.0032), safety of 100% (maximum change of 1 line of vision, p<0.0001). The pre and post-surgical contrast sensitivity test maintained the same visual acuity, however, the percentage in the spatial frequency of cycles 1.5, 3, 6, 12 and 18 decreased (p 0.785), the optical aberrations that increased were vertical and horizontal inclination, blur, vertical and horizontal coma, and spherical aberration (p <0.0001, Chi-square) (Odds Ratio 3.350), finally in the in the tomographic maps of anterior and posterior elevation there was no pathological change.
Conclusions :
SMILE surgery in terms of efficacy, precision and safety met the expected objective, however it is not the ideal technique in high astigmatism due to undercorrection; contrast sensitivity, optical aberrations and tomographic elevation maps did not show any statistically significant difference, so this refractive technique is ideal in cases where spherical refractive error predominates.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.