Comparison of 2 femtosecond lasers for laser in situ keratomileusis flap creation

Abstract

To compare the morphology of laser in situ keratomileusis (LASIK) flaps created by 2femtosecond lasers. Ophthalmic Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China. Comparative case series. The RTVue optical coherence tomography (OCT) device was used to measure the morphology of LASIK flaps created with an Intralase FS60 (Group 1) or Femto LDV (Group 2) femtosecond laser 1 week postoperatively. Nominal flap thickness was 110 μm for both devices. Group 1 comprised 408 flaps and Group 2, 408 flaps. The mean central flap thickness was 109.34 μm ± 7.57 (SD) in Group 1 and 103.91 ± 6.07 μm in Group 2 (P<.001). The mean flap thickness in Group 2 (105.37 ± 4.56 μm) was significantly thinner than in Group 1 (110.29± 6.95 μm) (P<.001). Corneal flaps in the 2 groups were uniform and regular, showing an almost planar configuration. The 2 groups had similar predictability; the mean deviation in flap thickness was 6.59 μm in Group 1 and 6.56 μm in Group 2 (P=.877). The maximum deviation from the intended 110 μm thickness of 18 measurements was 7.1 μm in Group 1 and 7.6 μm in Group2. The flaps in Group 2 were thinner than in Group 1. The 2 groups had similar predictability and uniformity in flap creation. No author has a financial or proprietary interest in any material or method mentioned.