Laser In Situ Keratomileusis (LASIK) Combined with Prophylactic Corneal Cross-Linking for Correction of Myopia: Regional Analysis of Corneal Morphology

Abstract

Introduction: This study evaluated the outcomes of laser in situ keratomileusis (LASIK) combined with prophylactic corneal collagen cross-linking (CXL) in correcting myopia in cases with increased estimated risk of postoperative corneal ectasia, detected by regional analysis of corneal morphology.<p> <p>Methods: The retrospective study included 180 eyes of 99 patients. Group 1 (94 eyes of 49 patients) with increased risk of postoperative corneal ectasia, as detected by ‘‘Ectasia Risk Factor Score System for LASIK’’, underwent femtosecond laser-assisted LASIK (FS-LASIK) combined with prophylactic CXL, using short riboflavin soaking time and low UV energy. Group 2 (86 eyes of 50 patients) with normal corneal topography, who underwent FS-LASIK alone, were used as controls. Refractive and visual outcomes and Scheimpflug topo/tomography were analyzed preoperatively and 1 week, 1 month, and 12 months postoperatively. Mean regional corneal curvature (M) values for three subregions (the central 3.0 mm region, the paracentral 3.0–6.0 mm region, and the peripheral 6.0–9.0 mm region) of both anterior and posterior surfaces were calculated. <p>Results: An increase in flattening of the peripheral anterior region and more steepening of the posterior paracentral region were shown at 12 months compared to 1 month postoperatively in group 1. The findings were significantly more pronounced than in group 2 (P \0.001 and P = 0.035, respectively). The refractive and visual outcomes were comparable in the two groups. <p>Conclusions: Prophylactic CXL seems to influence corneal regional reshaping after surgery, while not affecting the 1-year visual and refractive results.