To compare the visual outcomes of topography-guided and non-topography-guided PRK with simultaneous and sequential CXL treatment in patients with keratoconus.

This study included 69 eyes (38 patients) with keratoconus (stages 1-2 according to Amsler-Krumeich classification) in two groups which underwent topography-guided and non-topography-guided PRK with simultaneous and sequential CXL. Outcome measures were pre and postoperative uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), manifest refraction, keratometry and contrast sensitivity.

All evaluated visual, refractive, and contrast sensitivity parameters demonstrated a highly significant improvement in the two groups (all p < 0.05). A significant improvement was observed in keratometry in all groups and a significant difference was determined between topo-guided groups compared to non-topo-guided groups (p˂0.05). The improvement in all parameters was stable until the end of follow-up. Likewise, no significant difference was determined between the two groups in visual and refractive results.

The treatment options in the two groups are safety, efficacy and predictability to correct the spherocylindrical error in mild and moderate keratoconus. In this study, we did not find any significant difference between groups in the recorded objective results