Laser in situ keratomileusis for myopia up to -11 diopters with up to -5 diopters of astigmatism with the summit autonomous LADARVision excimer lasersystem

Objective: To assess the safety and effectiveness of the Summit Autonomous LADARVision active tracking narrow beam excimer laser system for laser in s itu keratomileusis (LASIK) correction of myopia and astigmatism. Design: A multicenter, prospective noncomparative case series. Participants: This cohort consisted of 177 eyes corrected for spherical myo pia up to -11 diopters (D) and 170 eyes corrected for myopia up to -11 D sp herical equivalent with astigmatism up to -5 D. Interventions Treatments were performed at four sites in the United States using a 6-mm optic zone for spherical myopes and a 5.5-mm optic zone with a l-mm blend for astigmats. Main Outcome Measures: Visual acuity, subjective refraction, vector analysi s, subject satisfaction, intraocular pressure, complications, and adverse r eactions. Results: Six-month follow-up was available on 157 spherical eyes and 113 as tigmatic eyes. For spherical myopes, uncorrected visual acuity (UCVA) was 2 0/20 or better in 60.5%, 20/25 or better in 80.3%, and 20/40 or better in 9 3.9%. The mean spherical equivalent was -0.29 +/- 0.45 D with 75.2% +/- 0.5 0 D and 94.9% +/- 1.00 D of intended. A loss of two lines of best spectacle -corrected visual acuity (BSCVA) occurred in 0.6%, and no eyes lost greater than two lines of BSCVA. For astigmatic myopes, UCVA was 20/20 or better i n 52.0%, 20/25 or better in 74.5%, and 20/40 or better in 94.1%. The mean s pherical equivalent was -0.23 +/- 0.49 D with 75.2% +/- 0.50 D and 95.6% +/ - 1.00 D of intended. A loss of two lines of BSCVA occurred in 0.9%, and no eyes lost greater than two lines of BSCVA. Vector analysis showed that 99% of the intended cylinder was corrected on average with a mean angle of err or of 4.2 degrees. Refractive stability was achieved between 1 and 3 months in 97.5% of spherical eyes and 99.4% of astigmatic eyes and confirmed betw een 3 and 6 months in 100% of both spherical and astigmatic eyes. Conclusions: Eyes treated for myopia up to -11 D of spherical equivalent wi th or without astigmatism up to -5 D show early refractive stability, good UCVA outcomes, no significant loss of BSCVA, accurate correction of astigma tism, and slight undercorrection without a change from the photorefractive keratectomy algorithm and with a single treatment. Ophthalmology 2001;108:3 09-316 (C) 2001 by the American Academy of Ophthalmology.