EPITHELIAL REMODELLING IN MYOPIA AFTER KERATOREFRACTIVE LENTICULE EXTRACTION

We analyzed longitudinal epithelial changes after the treatment of myopia with Keratorefractive Lenticule Extraction (KLEx) and the zonal change in epithelial thickness up to 12 months after SmartSight lenticule extraction for myopic astigmatism with the SCHWIND ATOS femtosecond laser system

Private practice.

We used optical coherence tomography data and analyzed changes in the epithelium after treatment. We aimed to ascertain how much epithelium hyperplasia occurred after KLEx; for this, we used data from 80 eyes treated with SmartSight with the SCHWIND ATOS, with a complete follow-up from POD1 to 12 months postoperative. 80 treated eyes with preoperative spherical equivalent (SEq) from -1.25D to -9.88D and preoperative central epithelial thickness from 46µm to 67µm were retrospectively reviewed for up to 12 months postoperatively. The mean age of the patients was 29±6 years with a mean SEQ of -4.72±1.97 diopters (D) and a mean magnitude of refractive astigmatism of 0.90±0.89 D.

Postoperative central epithelial thickness at 12-month follow-up was 2±5µm thicker than preoperatively. The other epithelial zones (nasal, superior, temporal, inferior) thickened by +4±4µm.  The epithelial change showed larger variability at postoperative day 1 (POD1) and stabilized from 1-week onwards.  Yet, postoperatively, the change in epithelium was not different for the different zones, and it did not correlate with the achieved refractive changes for any zone at any time point. 

 The changes in epithelial thickness after KLEx for moderate myopia with SmartSight using SCHWIND ATOS were minimal, indicating a low level of epithelial hyperplasia without resembling a regression-inducing lentoid. Findings suggest that KLEx with SCHWIND ATOS has a subtle impact on the epithelial thickness (with postoperative epithelium becoming slightly thicker). The differences remain, though, below any clinical relevance.