Comparative effectiveness of VISUMAX 800 with keratorefractive lenticule extraction and FS-LASIK in the treatment of myopic astigmatism

PURPOSE: To compare the visual and refractive outcomes of keratorefractive lenticule extraction (KLEx) using the VISUMAX 800 femtosecond laser and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) performed using the VISUMAX 800 femtosecond laser and the EX500 excimer laser in the treatment of myopic astigmatism. SETTING: Single-center, private ophthalmology center. DESIGN: Retrospective comparative study. METHODS: 237 eyes (133 KLEx, 104 FS-LASIK) were evaluated. Cyclotorsion alignment in KLEx was achieved using the Callisto Eye system integrated with VISUMAX 800. Refractive outcomes, vector analysis (Alpins method), and safety and efficacy indices were compared between groups at 1 month and 6 months postoperatively. RESULTS: At 6 months, both groups achieved comparable uncorrected distance visual acuity (0.01 ± 0.04 logMAR) and corrected distance visual acuity. Mean spherical equivalent was closer to emmetropia in the KLEx group (-0.04 ± 0.18 diopters [D] vs -0.10 ± 0.15 D, P = .007). Residual cylinder was lower in KLEx (-0.14 ± 0.19 D vs -0.20 ± 0.20 D, P = .010). Vector analysis showed lower difference vector in KLEx (0.14 ± 0.19 D vs 0.21 ± 0.21 D, P = .009), while FS-LASIK had a slightly higher correction index (correction index: 1.02 vs 0.97, P = .005). CONCLUSIONS: Both KLEx and FS-LASIK performed using the VISUMAX 800 achieved excellent refractive outcomes, with KLEx procedures incorporating an image-guided static cyclotorsion alignment strategy and demonstrating excellent refractive and vector analysis results.