Changes Between Lenticule Extraction and Femtosecond Laser-assisted Laser in Situ Keratomileusis

Four femtosecond incisions were created in succession: the posterior surface of the refractive lenticule (spiral in), the lenticule border, the anterior surface of the refractive lenticule (spiral out), and the corneal flap in the superior region. After the suction was released, the flap was opened using a thin, blunt spatula and the free refractive lenticule was subsequently grasped with a forceps and extracted, after which the flap was repositioned carefully.

track distance and spot distance were 3.0 μm during flap creation and 1.5 μm during flap side-cutting. The flap diameter was 8.0 mm, and flap thickness was set to 105 μm. Side-cut angle and hinge angle were 90°and 50° respectively. The flaps were created by laser scanning in spirals from the periphery to the center of the pupil. An excimer laser system was used in the subsequent ablation of the stromal bed with a 6.0 mm optical zone. Once the excimer ablation was completed, the flap was repositioned in a similar fashion as in routine LASIK.