Abstract:AIM: To explore the effects of femtosecond laser and mechanical lamellar blade excision laser in situ keratomileusis(LASIK)on corneal flap thickness stability and dry eye syndrome.
METHODS: Retrospective analysis of 80 patients with myopia who underwent LASIK in our hospital. According to different methods of flapping, it is divided into femtosecond laser group and mechanical laminating knife group. The flap thickness of the two groups of patients at different time points(1h, 1d, 1wk, 1mo, 3mo)were measured. The differences in corneal apex 1, 2, 3mm and corneal apex flap thickness in different directions were compared. The incidence of dry eye syndrome was compared between 1 and 3mo, 1a, 2a after surgery.
RESULTS: The apex thickness of the corneal flap of the femtosecond laser group is 99.62±4.50μm, and the thickness of the apex of the mechanical lamellar knife group is 125.25±12.81μm.The thickness of the corneal flap at different centrifugal points of the femtosecond laser flap is relatively uniform, while the thickness of the corneal flap of the mechanical lamellar knife varies greatly. The OSDI scores of the mechanical lamellar group were higher than those of the femtosecond laser group at 1, 3, 1, and 2a postoperatively(P<0.01). At 2a of follow-up, the incidence of dry eye in the femtosecond laser group was lower than that in the mechanical lamellar group(χ2=4.692, P=0.030). At 1 and 2a postoperatively, the proportion of mild dry eye in the femtosecond laser group was higher than that in the mechanical lamellar group(P=0.044, 0.001).
CONCLUSION: Compared with the mechanical lamellar scalpel, the corneal flap thickness of patients with femtosecond laser LASIK is better, more uniform and less error. And the incidence of dry eye after surgery is lower, with mild dry eyes.
