{Reference Type}: Comparative Study
{Title}: The comparison of visual outcomes, aberrations, and Bowman's layer micro-distortions after femtosecond laser small-incision lenticule extraction (SMILE) for the correction of high and moderate myopia and myopic astigmatism.
{Author}: Qin B;Zhao J;Li M;Yao P;Zhou X;
{Journal}: BMC Ophthalmol
{Volume}: 19
{Issue}: 1
{Year}: Jun 2019 27
{Factor}: 2.086
{DOI}: 10.1186/s12886-019-1135-9
{Abstract}: BACKGROUND: This study compares the clinical outcomes of femtosecond laser small-incision lenticule extraction (SMILE) for the correction of myopia and myopic astigmatism greater than - 10 D, and - 10 D or less respectively.
METHODS: 60 eyes/patients were equally selected into group 1 (myopia and myopic astigmatism of - 10 D or less) and group 2 (myopia and myopic astigmatism of over - 10 D), both of which were treated with SMILE. Visual and refractive outcomes, corneal higher-order aberrations, and Bowman's layer micro-distortions were evaluated preoperatively, 3 months, and 6 months postoperatively.
RESULTS: LogMAR corrected distance visual acuity (CDVA) of group 1 and group 2 was - 0.069 ± 0.047 and - 0.053 ± 0.073 6 months postoperatively (P = 0.48). 100% eyes in group 1 and 97% in group 2 were within 1 D of targeted correction (P = 0.45). Meanwhile, 100% eyes in group 1 and 97% in group 2 had an uncorrected distance visual acuity of 20/25 or better (P = 0.20). Changes in corneal higher-order aberrations root mean square, coma, and trefoil were similar between the two groups but spherical aberration was higher in group 2 (P < 0.01). Micro-distortions were observed in 53% in group 1 and 77% in group 2. More micro-distortions were observed in group 2 (3.40 ± 2.66) than in group 1 (2.07 ± 2.29) (P = 0.041). The total number of micro-distortions was not correlated with postoperative CDVA (P = 0.77).
CONCLUSIONS: Visual outcomes showed similar results of SMILE for myopic correction of > - 10 D and ≤ - 10 D. Refractive outcomes showed slightly under-correction in higher myopic eyes. Higher myopic treatment tends to induce more spherical aberrations. Micro-distortions had no impact in visual and refractive outcomes.