THE PICOSECOND LASER FOR NONMECHANICAL LASER IN-SITU KERATOMILEUSIS

PURPOSE: To introduce the clinical use of the Nd:YLF picosecond laser as a nonmechanical microkeratome, METHODS: A.commercially available Nd :YLF picosecond laser (25 mu J/pulse, 30 psec, 1053 nm) was used to de liver intrastromal pulses of focused high power laser light to generat e a flap for laser in situ keratomileusis (LASIK) and perform picoseco nd laser keratomileusis (PLK) in two partially sighted patients with h igh myopia. RESULTS: Case #1: A 6 mm, 150 mu m flap for LASIK was succ essfully created and the underlying stroma treated with an excimer las er for a target correction of -15.00 D of myopia. Good corneal clarity and a refractive change of -14.00 D was recorded 2 months postoperati vely, Case #2: Both eyes of a high myope (-22.00 D right eye, -21.50 D left eye) underwent picosecond laser keratomileusis,removing a 3.2 mm diameter lenticule of 120 mu m thickness under a 200 mu m flap. Posto perative refraction was -2.00 D at 7 months in the right eye and -0.75 D at 2 months in the left eye with improvement of spectacle-corrected visual acuity from 20/200 to 20/70 in each eye. CONCLUSION: The Nd:YL F picosecond laser can be safely used in creating a corneal flap for L ASIK and in performing picosecond laser keratomileusis for high myopia . Future refinements in the laser will include a larger flap diameter and femtosecond pulsing capability.