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One-month outcomes of wavefront-guided LASIK for low to moderate myopia with the VISX STAR S4 laser in 32,569 eyes.

PURPOSE
To determine the safety and efficacy of wavefront-guided LASIK for the correction of low to moderate myopia, as performed by surgeons employed by Optical Express, a large corporate provider.


METHODS
Data were extracted from the Optical Express central database on 22,900 patients (42,143 eyes) who underwent primary LASIK to treat low to moderate myopia and/or astigmatism. All treatments used a wavefront-guided ablation profile and had a refractive target of emmetropia. Outcomes were evaluated using 1-month follow-up data, which were available for 32,569 eyes of 17,713 patients (77% follow-up). Complications were tabulated using all available data.


RESULTS
The mean manifest spherical equivalent (MSE) was reduced from -2.97 +/- 1.33 diopters (D) (range: -0.37 to -6.00 D) to -0.03 +/- 0.29 D (range: -3.50 to +4.50 D) 1 month after surgery. Ninety-four percent of eyes were within 0.50 D of the intended correction, and the correlation coefficient of the attempted versus achieved MSE was 0.96. Uncorrected visual acuity (UCVA) of 20/20 or better was achieved in 92% of eyes; 99% of eyes achieved UCVA of 20/40 or better. Among patients who had bilateral laser vision correction, 98% achieved 20/20 uncorrected binocular vision. Average best spectacle-corrected visual acuity (BSCVA) improved slightly 1 month after surgery (mean change: +0.01 logMAR). There were 210 (0.67%) eyes that lost 2 or more lines of BSCVA; however, all eyes were 20/40 or better. Intraoperative complications occurred in 25 eyes (0.06%; 1:1686), and postoperative complications occurred in 210 eyes (0.64%; 1:155). The most common complications were dry eye (n=58; 0.18%; 1:562) and mild diffuse lamellar keratitis (grade 1 or 2) (n=58; 0.18%; 1:562).


CONCLUSIONS
Wavefront-guided LASIK can safely and effectively correct low to moderate myopia, as demonstrated by 1-month postoperative visual outcomes from a large number of patients.