Laser in situ Keratomileusis Using the Nidek EC-5000 or the Alcon LADARVision 4000 Systems

PURPOSE: To compare the refractive results of eyes with low to moderate myopia that underwent laser in situ keratomileusis with either the Nidek EC-5000 or the Alcon LADARVision 4000 excimer laser systems. METHODS: We performed a retrospective review of 114 LASIK procedures with either the Nidek EC-5000 (54 eyes) or the Alcon LADARVision 4000 (60 eyes) excimer laser systems. Preoperative refractive errors were similar and both populations were treated during the same time period. Data analyzed included uncorrected visual acuity (UCVA), spherical magnitude, spherical equivalent refraction, astigmatism power, astigmatism axis, and vector astigmatism change. RESULTS: Results at 6 months were analyzed. Spherical correction change was a mean -3.95 D for Nidek treated eyes and a mean -4.53 D for LADARVision treated eyes (P=.20). Mean spherical equivalent refraction change was -3.70 D for Nidek eyes and -4.20 D for LADARVision eyes (P=.23). Mean change in UCVA (LogMAR) was 1.05 for Nidek eyes and 0.99 for LADARVision eyes (P=.40). Mean astigmatism magnitude change was 0.71 D for Nidek eyes and 0.77 D for LADARVision eyes (P=.63). Mean vector-corrected astigmatism change was 0.93 D for Nidek eyes and 1.00 D for LADARVision eyes (P=.63). Mean vector-corrected astigmatism axis for Nidek eyes was 3.08 D and for LADARVision eyes 6.58 D (P=.70). CONCLUSION: There was no significant difference in refractive results in eyes treated with the Alcon LADARVision 4000 or the Nidek EC-5000 excimer laser systems. Inherent differences between the two laser systems are highlighted.