Influence of original flap creation method on incidence of epithelial ingrowth after LASIK retreatment.

PURPOSE: To compare the rate of epithelial ingrowth after LASIK retreatment among eyes with flaps created by femtosecond laser and those created by mechanical microkeratome.

METHODS: Postoperative results from 272 consecutive LASIK retreatments performed by a single surgeon over a 4-year period were reviewed retrospectively to identify cases that developed clinically significant epithelial ingrowth, defined as that which required surgical removal. Flaps for the original LASIK treatments were created using a mechanical microkeratome or femtosecond laser. The same technique to lift the flap at the time of retreatment was used in all eyes included in this study.

RESULTS: LASIK retreatment was performed in 132 eyes that had the initial flap created using a mechanical microkeratome (microkeratome group). Epithelial ingrowth was identified in 11 eyes of 9 patients. Surgical intervention to remove the epithelium from the stromal interface was required in 8 (6.1%) eyes. Femtosecond laser was used to create the initial LASIK flap in 140 eyes that required retreatment (femtosecond group). Epithelial ingrowth after LASIK retreatment was identified in 2 eyes of 1 patient in the femtosecond group (P=.004). Neither of these 2 eyes required surgical intervention to remove the epithelium from the stromal interface (P=.017).

CONCLUSIONS: Eyes with femtosecond laser-created flaps may be less likely to develop significant epithelial ingrowth after LASIK retreatment when compared with eyes in which the flap was created using a mechanical microkeratome. The difference in rate of epithelial ingrowth may be related to the geometry of the flap edge.