Laser in situ keratomileusis after penetrating keratoplasty

Purpose: To assess the outcomes of laser in situ keratomileusis (LASIK) after penetrating keratoplasty (PKP). Setting: Hospital de Clinicas de Porto Alegre, Department of Ophthalmology, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. Methods: Fourteen eyes of 13 patients who had LASIK after PKP were retrospectively reviewed, The interval between LASIK and PKP was at least 1 year, and the follow-up after LASIK was also at least 1 year. All patients had a stable refractive error for a minimum of 6 months after all sutures were removed, regular and symmetric topographic astigmatism, and a minimal ultrasonic central corneal pachymetry of 500 mum. The Chiron Automatic Corneal Shaper(R) and the Meditec Aesculap MEL 60 excimer laser were used. Results: At 12 months, mean myopia decreased from -5.33 diopters (D) +/- 4.22 (SD) to 0.19 +/- 1.71 D, mean hyperopia decreased from +/-5.04 +/- 3.32 D to + 0.42 +/- 0.46 D, and mean astigmatism decreased from 5.37 +/- 2.12 D to 2.82 +/- 2.42 D (47.5% of mean percentage reduction). Retreatment was necessary in 42.9% of eyes because of cylindrical undercorrection, Uncorrected visual acuity improved in 11 eyes (78.6%). Best spectacle-corrected visual acuity improved in 6 eyes (42.8%) and was maintained in 4 eyes (28.6%); 5 eyes (35.7%) lost 1 Snellen line. intraoperative complications included 1 buttonhole flap. Postoperative complications included interface epithelial ingrowth at the periphery (2 eyes) and pseudophakic retinal detachment 2 years after LASIK (1 eye). Conclusion: Laser in situ keratomileusis after PKP safely and predictably corrected the spherical component of the refraction. However, the predictability of LASIK in correcting post-PKP astigmatism was poor.