Vector Analysis of Moderate to High Myopic Astigmatism After Small-Incision Lenticule Extraction (Smile): 12-Month Follow-Up Publisher Pubmed



Jabbarvand M¹ ; Khodaparast M¹ ; Moravvej Z^{1, 2} ; Shahraki K¹ ; Ahmadi H^{1, 3} ; Shahraki K¹ ; Jamali A⁵ ; Narooienoori F⁵
Source: European Journal of Ophthalmology Published:2022

Abstract

Purpose: To evaluate the refractive outcomes of small-incision lenticule extraction (SMILE) surgery in moderate to high myopic astigmatism Study Design: Prospective interventional case series Methods: This study evaluated 111 eyes of 68 patients treated with femtosecond SMILE surgery for the correction of myopia and astigmatism. Inclusion criteria were myopia of − 0.5 D or more and astigmatism between − 1.0 D and −5.0 D. Refractive and visual measurements were obtained preoperatively, 1 and 12 month(s) postoperatively. Vector analysis was used to study the astigmatic outcomes at 12-month follow-up. Comparison of results in two groups of patients with astigmatism below and over 3.00 D was performed. Results: The preoperative mean spherical equivalent was −5.48 ± 2.17 D (range − 1.75 to − 10.00 D) and the mean cylinder was −2.02 ± 1.09 D (range − 1.00 to − 5.00 D). The mean postoperative cylinder value was −0.60 ± 0.52 D at 12-month visit. The 12-month safety and efficacy indices were 0.98 ± 0.07 and 0.97 ± 0.12, respectively. The high astigmatism group showed significantly lower safety and efficacy indices. The postoperative residual astigmatism was 0.5 D or less in 73% of the eyes. Higher amount of residual astigmatism was observed in the high astigmatism group. The angle of error was ± 5 degrees in 49% and ± 15 degrees in 87% of the eyes. Conclusion: SMILE surgery is effective and safe method for correcting myopic astigmatism. Vector analysis indicated a tendency for the under correction of astigmatism in subjects with high astigmatism. © The Author(s) 2022.