Introduction: Collagen cross-linking is a useful adjunct in preventing corneal ectasia after laser-assisted in situ keratomileusis (LASIK). This study aimed to evaluate whether prophylactic cross-linking in IntraLase LASIK affects optimum visual outcome and recovery time in the immediate post-surgery period and is associated with any side effects.

Methods: This was a retrospective case study on the right eyes of 100 Chinese subjects aged 18 to 40 years who underwent IntraLase LASIK. Fifty subjects who underwentcross-linking after completing LASIK (Group A) were compared with 50 subjects who did not undergo LASIK (Group B). Cases were evaluated for pre- and post-operative spherical equivalent, uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), recovery time and presence of side effects.

Results: At 1 week post-LASIK, mean (SD) UDVA of Group A subjects was poorer than Group B, at 1.05 (0.19) vs 1.17 (0.19) (p = 0.036); however, there was no significant difference in CDVA (p = 0.095). By 1 month post-LASIK, differences in both UDVA and CDVA were insignificant (p = 0.055, 0.106, respectively). Mean recovery time was 2.72 (95% confidence interval [CI] = 0.64-4.7) days longer in Group A (p = 0.010), although by 1 month post-LASIK, both groups were able to achieve CDVA equal to or better than that achieved pre-LASIK. Incidence of mild inflammation and dry eyes post-LASIK was similar in both groups (p = 1.00, 0.749, respectively); no other complications were observed.

Conclusion: No differences in visual outcomes at and occurrence of side effects at 1 month post-LASIK were observed between subjects who underwent cross-linking prior to refractive surgery and those who did not. However, the group that underwent cross-linking had a slightly longer mean recovery time. Our study supports prophylactic cross-linking as a safe procedure that does not affect immediate visual outcomes among the Chinese population when used in adjunct with LASIK surgery.