A. Mularoni

Two-step LASIK with topography-guided ablation to correct astigmatism after penetrating keratoplasty.

PURPOSE To assess the efficacy, predictability, stability, and safety of a two-step LASIK procedure using topography-guided ablation to correct astigmatism after penetrating keratoplasty. METHODS Fifteen eyes of 15 patients underwent a two-step LASIK procedure at the Maggiore Hospital of Bologna, Italy. In the first step, a flap was created using the Hansatome microkeratome. In the second step, topography-guided ablation using the LaserSight LSX was planned with interactive software (CIPTA) once topographical and refractive stabilization had been obtained. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), cylindrical correction, gain of lines of BSCVA, spherical equivalent refraction, and complications were analyzed. RESULTS Minimum follow-up was 12 months (range: 12 to 30 months). Uncorrected visual acuity improved in all 15 (100%) eyes. At the last postoperative examination, 11 (73%) eyes had UCVA > or = 20/40. Nine (60%) eyes were within 1.0 diopter (D) of the attempted correction. Mean postoperative astigmatism was -1.67 (range: -3.5 to 0; standard deviation: 1.26). Index of success of astigmatic correction was 0.26. No patient lost Snellen lines of BSCVA. Intraoperative complications included two buttonhole flaps, and postoperative complications included one flap retraction. No further laser treatment was needed. CONCLUSIONS The two-step LASIK procedure using topography-guided ablation reduces spherical and cylindrical refractive error due to penetrating keratoplasty. Topography-guided ablation also proved to be effective in correcting irregular astigmatism.

Induced astigmatism after near-clear hinge incision

Purpose: To evaluate astigmatism induced by the near‐clear hinge incision. Setting: Casa di Cura Villa Toniolo, Bologna, and Day Hospital Nuova Ricerca, Rimini, Italy. Methods: The results in 100 eyes having phacoemulsification with a 3.2 or 4.1 mm temporal near‐clear hinge incision were evaluated for a maximum of 6 months. Corneal curvature was measured using computerized videokeratography, and surgically induced astigmatism was computed by vector analysis. Surgically induced corneal topographic changes were also evaluated. Results: Mean induced cylinder in the 3.2 mm incision group was 0.4 diopter (D) ± 0.2 (SD) 6 months after surgery; there was no significant difference in the values at 4 days and 6 months. Mean induced cylinder in the 4.1 mm incision group was similar at 1 and 6 months (0.47 and 0.45 D, respectively). However, it was significantly higher at 4 days (0.56 D). Vector decomposition analysis showed that the with‐the‐rule component was prevalent and remained constant over 6 months. Topographic analysis showed localized wound‐related flattening with minimal central corneal changes. Conclusion: The near‐clear hinge incision was almost astigmatically neutral and resulted in self‐sealing incisions that did not leak.