Outcomes of LASIK and PRK in previous penetrating corneal transplant recipients

Purpose: To evaluate the safety and efficacy of excimer laser refractive surgery in correcting refractive error in eyes that have undergone previous penetrating keratoplasty (PK). METHODS: Twenty-three keratorefractive procedures on 16 eyes from 16 consecutive subjects were evaluated between 2002 and 2008. Each patient presented a previous history of a PK with subsequent postoperative myopia and astigmatism. Keratometric value, manifest refraction, best-corrected visual acuity, uncorrected visual acuity, and complications were determined. RESULTS: There were a total of 14 photorefractive keratectomy (PRK) procedures performed on 11 eyes and 9 laser in situ keratomileusis (LASIK) procedures performed on 5 eyes. In the PRK group, the preoperative post-PK manifest refractive spherical equivalent and cylindrical error were -6.22 ± 6.23 diopter and 5.23 ± 2.26 D, respectively. The PRK postoperative manifest refractive spherical equivalent and cylindrical error were -3.61 ± 4.23 D (P=0.25) and 3.21 ± 1.78 D (P=0.02), respectively. In the LASIK group, the preoperative post-PK manifest refractive spherical equivalent and cylindrical error were -3.05 ± 3.29 D and 4.11 ± 2.38 D, respectively. The LASIK postoperative manifest refractive spherical equivalent and cylindrical error were -1.51 ± 2.02 D (P=0.24) and 2.08 ± 1.26 D (P=0.03), respectively. There was a 2-line or greater improvement of uncorrected visual acuity in 8 of the 14 PRK treatments and 5 of the 9 LASIK treatments. There were two episodes of acute graft rejection. One of the episodes resolved with topical and oral corticosteroids, and the other episode required a repeat corneal transplantation. CONCLUSIONS: PRK and LASIK are effective tools in reducing surgically induced astigmatism after penetrating corneal transplantation in most patients in this case series. The reduction of astigmatism may allow improved contact lens or spectacle fitting to achieve best-corrected binocular visual acuity.