The primary objective of this study is to compare WaveLight ALLEGRETTO WAVE™ wavefront guided or optimized excimer laser treatment with the AMO/VISX CustomVue™ and the LADARVision 4000 excimer laser treatment using both subjective and objective outcome measures. This comparison will be made between fellow eyes of the same patient following excimer laser ablation using the WaveLight ALLEGRETTO WAVE™ Excimer Laser System in one eye and the AMO/VISX CustomVue™ or the LADARVision 4000 excimer laser in the contralateral eye .