To compare contrast sensitivity and visual outcome after photorefractive keratectomy (PRK) for correction of moderate myopia with or without astigmatism with two methods of excimer laser: tissue saving and wavefront optimized.

This prospective study comprised 152 eyes of 80 patients with the mean spherical equivalent (SE) -4.5±1.02 who underwent PRK in two groups: 76 eyes of 39 patients were treated with tissue saving ( Technolas 217 z ) and 76 eyes of 41 patients were treated with wavefront optimized ( Allegretto Wave Eye Q ) method. Preoperative and 3 months postoperative photopic and mesopic contrast sensitivity were compared between two groups.

No statistically significant differences were seen in best spectacle corrected visual acuity, uncorrected visual acuity and spherical equivalent between two groups postoperatively. No statistically significant differences were seen in contrast sensitivity changes between two groups in photopic and mesopic conditions. Higher order aberrations and Q Factor increased in both groups postoperatively and statistically significant differences were seen between two groups. Tissue saving group had more increases in higher order aberrations and Q than wavefront optimized group. However contrast sensitivity changes and patient satisfaction were comparable between the two groups.

Both platforms are effective in correcting moderate myopia with or without astigmatism with Tissue saving method causing more increases in higher order aberrations and Q than wavefront optimized group but no difference in contrast sensitivity changes and patient satisfaction.