Early visual outcomes and optical quality after femtosecond laser small-incision lenticule extraction for myopia and myopic astigmatism correction of over -10 dioptres.

Abstract

To investigate early visual and refractive outcomes, corneal stability and optical quality after femtosecond laser small-incision lenticule extraction (SMILE) for treating myopia and myopic astigmatism over -10D. Thirty eyes (30 patients) with myopia and myopic astigmatism of over -10D were treated with VisuMax® femtosecond laser (version 3.0; Carl Zeiss Meditec AG, Jena, Germany). Six months postoperative safety, efficacy and predictability were evaluated. Corneal Scheimpflug topography was measured preoperatively, 1day, 3months and 6months postoperatively. Wavefront aberrations were measured preoperatively, 3months and 6months postoperatively. Six months postoperatively, LogMAR uncorrected and corrected distance visual acuity (CDVA) were -0.013±0.086 and -0.073±0.069, respectively. 73% (97%) of eyes were within 0.5 (1) D of target refraction. No eyes lost CDVA, 43% (13 eyes) gained one line and 7% (two eyes) gained two lines. Mean corneal back curvature (KMB) and posterior central elevation (PCE) did not change significantly comparing preoperative and 6months postoperative data (p=0.91 and 0.77, respectively). Comparing 1day with 6months postoperative data, central corneal thickness (CCT), mean corneal front curvature (KMF), KMB and PCE did not change significantly (p=0.27, 0.07, 0.52, 0.71, respectively). Total higher-order aberration (HOA), spherical aberration and coma increased significantly (p<0.01) but trefoil remained stable (p=0.49). Our results indicate that SMILE can correct myopia and myopic astigmatism of over -10D predictably. No early ectasia was observed. Long-term changes in visual quality and corneal stability require further investigation.