Lasik is a laser refractive procedure. It is meant to change or eliminate the need for glasses correction. It stands for laser assisted in situ keratomileusis. In LASIK, a microkeratome is first used to create a very thin flap of corneal tissue. This instrument is analogous to a carpenter's plane. Then the laser treatment is performed with the excimer laser. Finally the flap is is put back in place to cover the laser-treated area. While there is a faster return of vision with lasik, the long term results are about equal to those of PRK.