Effect of Myopic Femtosecond Laser-Assisted LASIK on Anterior Chamber Inflammation (Flare Values) and Corneal Endothelium: A Prospective before and after Study.

Purpose: This study aimed to investigate whether femtosecond laser-assisted LASIK (FS-LASIK) surgery causes inflammation in the anterior chamber and to analyze its effect on endothelial cells.

Methods: This prospective, longitudinal study included left eyes of 30 patients (19 females) who had undergone FS-LASIK surgery due to myopia and myopic astigmatism. Endothelial cell density (ECD) and morphological measurements were performed using a specular microscopy, and laser flare photometry was used to measure the anterior chamber flare values on the day of surgery. iFS™ Advanced FS and VISX STAR S4-IR Wavescan Excimer Laser platforms were used. Flare measurements were repeated on the postoperative 1 day and 7 day and the 1 and 3 months. The endothelial measurements were repeated in the 3 month.

Results: Preoperatively, the mean flare was 5.59 ± 1.24 photons/ms; it was 6.49 ± 2.42 on the postoperative 1 day, 5.87 ± 2.27 on the 7 day, 5.68 ± 1.66 on the 1 month, and 5.35 ± 1.24 on the 3 month. A significant difference was observed only between the preoperative and postoperative 1 day flare values (=0.047). The decrease in the ECD was clinically insignificant but statistically significant, with an average of 97.0 ± 209.9 cell count/mm (3.3%, =0.017). However, there was no significant change in the coefficient of variation (=0.448) and hexagonality (=0.096). No significant correlation was found between the increase in the flare value on the postoperative 1 day and variables. A significant correlation was found between the decrease in ECD and the preoperative ECD ( = 0.356, =0.027).

Conclusion: FS-LASIK caused minimal inflammation in the anterior chamber on only the 1 postoperative day; additionally, a minimal decrease of cell count with no morphological changes were noted in the endothelial cells on postoperative 3 month. This trial is registered with NCT04899258.