Femtosecond laser-assisted penetrating keratoplasty: Stability evaluation of different wound configurations

PURPOSE: To evaluate the stability of different wound configurations for full-thickness penetrating keratoplasty (PK) by using the femtosecond laser in a laboratory model. METHODS: Twenty-two human corneoscleral rims were mounted on an artificial anterior chamber and underwent full-thickness keratoplasty with the femtosecond laser to create different wound configurations. Five samples were assigned to the traditional PK group, 5 to the "top hat" group, 4 to the "mushroom" group, 4 to "zig zag," and 4 to the "Christmas tree" wound configuration. Wound bursting pressure was evaluated after placement of 4, 8, and 16 interrupted sutures. RESULTS: In the traditional PK group, leakage occurred at 0 ± 0, 21.6 ± 2.5, and 49 ± 6.6 mm Hg after placement of 4, 8, and 16 sutures, respectively. No statistically significant difference was noticed in burst pressure with the zig zag and Christmas tree wound configuration compared with the traditional PK group. In the top hat and mushroom groups, burst pressure was 102 ± 16.8 (P = 0.008) and 65.8 ± 5.3 (P = 0.03) mm Hg, respectively, after placement of the 16 sutures. CONCLUSIONS: The femtosecond laser-assisted top hat wound configuration for PK was found to be the most mechanically stable compared with the traditional method and mushroom, zig zag, and Christmas tree configurations.