lasik retreatment for myopia and myopic astigmatism

purpose: to evaluate the results of laser in situ keratomileusis (lasik) retreatment in  patients with postoperative regression. methods: in a retrospective interventional case series, 153 eyes of 113 patients who had undergone lasik retreatment for postoperative regression were evaluated. both initial lasik and retreatment were performed with a nidek: ec 5000 excimer laser, and flap was made with a moria microkeratome. results: mean age was 29.63 ± 2.2 yr (range, 20 to 54 yr) and mean follow–up was 11 months (range, 3 to 34  mth) after the initial surgery and 13.1 months (range, 12 to 18 mth) after retreatment. retreatment was performed 3-34 months after the primary lasik. mean spherical equivalent (se) was -5.39 ± 2.69 diopters (d) (range, -1.50 to -14.00 d) before initial lasik and   -1.76 ± 1.08 d (range, -0.50 to -5.00 d) before retreatment. mean astigmatism was -1.38 ± 1.07 d (range, -0.50 to -5.00 d) before initial lasik and -1.12 ± 0.50 d (range, -0.50 to -2.50 d) before retreatment. one year after retreatment, mean ucva was 20/25, and mean se was -0.29 ± 0.02 d. best corrected visual acuity (bcva) improved in all eyes. two eyes received more than one retreatment. twenty eyes had flap wrinkling, 2 eyes had diffuse lamellar keratitis (dlk), and 2 eyes had epithelial ingrowth after the initial lasik. four eyes had epithelial ingrowth and 2 eyes developed mild keratectasia after retreatment. conclusions: lasik retreatment is a safe and effective option with small amounts of myopia and myopic astigmatism regression. the rate of retreatment is higher in patients with myopic astigmatism and in patients with less than 40 years of age, also the risk of complications in retreatment is higher than the initial lasik. refractive changes are more stable after retreatment. the risk of keratectasia is higher in final residual stromal bed thickness less than 250 mm after the reoperation.