Laser in situ keratomileusis for-6.00 to-18.00 diopters of myopia and up to-5.00 diopters of astigmatism: 15-year follow-up

PURPOSE: To evaluate the long-term outcomes of laser in situ keratomileusis (LASIK) for high myopia with or without astigmatism. SETTING: Vissum Institut Oftalmologico de Alicante and Miguel Hernandez University, Alicante, Spain. DESIGN: Retrospective prospective case series. METHODS: Laser in situ keratomileusis was performed using the Visx 20/20 excimer laser. The minimum follow-up was 15 years. The main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction, and corneal topography. RESULTS: This study included 40 patients (40 eyes) with a mean age of 51.08 years +/- 6.67 (SD) (range 41 to 60 years) with high myopia (-6.00 to -18.00 diopters [D]). At 15 years, the safety index was 1.23 and the efficacy index, 0.95. During the follow-up, a significant increase in the dioptric power of all keratometric variables was detected (P <=.028, Friedman test), the most notable increase occurring between 3 months and 1 year (P <=.005). At 15 years, 46.15% of the eyes were within +/- 1.00 D of the attempted spherical equivalent and 64.10% were within +/- 2.00 D. The UDVA at 15 years was 20/25 or better in 43.59% of eyes and 20/40 or better in 64.10% of eyes. The postoperative CDVA was significantly better than preoperatively (P<.001). The postoperative complications were minor except in 1 eye in which ectasia occurred. CONCLUSIONS: Laser in situ keratomileusis for high myopia was safe over the long term. However, significant myopic regression with time was detected. Low preoperative pachymetry and low residual stromal bed were predictors of keratometric regression.