The term "laser" is an acronym for Light Amplification by Stimulated Emission of Radiation. The two lasers that are presently being used to any degree for refractive eye surgery are the Holmium: YAG Laser and the Excimer Laser. The Holmium: YAG Laser is being currently used on an investigational basis only. The Excimer Laser is now approved with certain restrictions for the treatment of mild to moderate cases of nearsightedness.