Femtosecond thin-flap LASIK for the correction of ametropia after penetrating keratoplasty

PURPOSE: To evaluate the outcomes of LASIK with thin femtosecond laser flaps for the treatment of refractive errors after penetrating keratoplasty (PK). METHODS: Eleven consecutive eyes underwent femtosecond thin-flap LASIK 51.6±42.1 months (range: 13 to 156 months) after the initial PK. A full ophthalmic assessment was performed before femtosecond LASIK and 6 months after surgery. Postoperative retreatments were also noted. RESULTS: No intra- or postoperative complications were observed. The outcomes of nine eyes that completed at least 6 months' follow-up and had no retreatment during that period were evaluated. Mean preoperative myopia decreased from -3.60±1.60 diopters (D) to +1.00±2.70 D 6 months after surgery, and mean hyperopia decreased from +3.50±1.30 D preoperatively to +0.30±0.70 D 6 months after surgery. Mean preoperative astigmatism decreased from -6.60±3.60 D to -2.90±2.00 D 6 months after surgery. At 6 months, the mean preoperative myopic spherical equivalent refraction (SE) decreased from -6.40±2.00 D to -0.02±2.20 D, and mean hyperopic SE from +0.80±2.80 D to -0.60±0.60 D. At 6 months postoperatively, 67% (6/9) of eyes were within 1 line of preoperative best spectacle-corrected visual acuity and 33% (3/9) gained ≥2 lines. CONCLUSIONS: Femtosecond thin-flap LASIK is a safe procedure in eyes with previous PK. This procedure is reasonably predictable, especially for the spherical component of the refraction. Creating the flap with the femtosecond laser and performing excimer laser ablation within the corneal graft limits without involving the graft-host junction provides the advantage of performing the entire procedure in one step.