laser in situ keratomileusis for correction of myopia and astigmatism after penetrating keratoplasty

purpose: to assess the efficacy and safety of laser in situ keratomileusis (lasik) for correction of residual myopia and astigmatism after penetrating keratoplasty (pk). methods: in this prospective interventional case series, lasik was performed on 14 eyes of 13 patients unable to wear glasses or contact lenses after pk. the interval between lasik and pk was at least one year. all patients had stable refractive error and regular and symmetric astigmatism for a minimum of 4 months after removal of all sutures. uncorrected visual acuity (ucva), best spectacle corrected visual acuity (bscva), endothelial cell count and corneal transplant integrity were recorded before and 1, 3, 6, and 12 months after lasik surgery. results: mean spherical equivalent (se) refractive error before lasik was -6.44±2.19 diopters (d), which was reduced to -1.47±2.03 d at the last postoperative visit (p= 0.002). mean cylinder before lasik was 3.69±1.84 d, which was reduced to 2.55±1.15 d at final follow up (p= 0.003). bcva remained unchanged in 4 eyes, improved by 1 to 4 lines in 8 eyes and decreased by 1 and 4 lines in 2 other eyes. one case of flap buttonhole occurred intraoperatively. there were no surgical corneal transplant complications. the difference between mean endothelial cell count before and after lasik was not significant. conclusion: lasik is an effective and relatively safe treatment modality for residual myopia and astigmatism after pk in patients who are spectacle and contact lens intolerant. lasik seems to be more effective and predictable in treating the myopia than astigmatism.