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

Abstract

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 1st day and 7th day and the 1st and 3rd months. The endothelial measurements were repeated in the 3rd month. Results. Preoperatively, the mean flare was 5.59 ± 1.24 photons/ms; it was 6.49 ± 2.42 on the postoperative 1st day, 5.87 ± 2.27 on the 7th day, 5.68 ± 1.66 on the 1st month, and 5.35 ± 1.24 on the 3rd month. A significant difference was observed only between the preoperative and postoperative 1st day flare values ( p = 0.047 ). The decrease in the ECD was clinically insignificant but statistically significant, with an average of 97.0 ± 209.9 cell count/mm2 (3.3%, p = 0.017 ). However, there was no significant change in the coefficient of variation ( p = 0.448 ) and hexagonality ( p = 0.096 ). No significant correlation was found between the increase in the flare value on the postoperative 1st day and variables. A significant correlation was found between the decrease in ECD and the preoperative ECD (r = 0.356, p = 0.027 ). Conclusion. FS-LASIK caused minimal inflammation in the anterior chamber on only the 1st postoperative day; additionally, a minimal decrease of cell count with no morphological changes were noted in the endothelial cells on postoperative 3rd month. This trial is registered with NCT04899258.

Clinical Evaluation of Corneal Endothelial Parameters following Laser Refractive Surgery in Myopic Eyes: A Review

“…Inflammatory pathways and arachidonic acid metabolites in the cornea may theoretically trigger inflammation in the anterior chamber. This was not confirmed by Özbilen et al [60] in a three-month FemtoLASIK study. At the same time, they found a statistically significant 3.3% decrease in ECD.…”

Comparison of implantation of posterior chamber phakic IOL implantation and laser vision correction in terms of corneal endothelial cells: 3-year observational paired-eye study

“…LASIK and PRK might affect endothelial cells through different mechanisms. 22,23 However, to the authors' knowledge, no previous studies have investigated this possibility. Therefore, our results should be interpreted with care.…”

Effect of mitomycin C on the corneal endothelial cells of Saudi patients with myopia after transepithelial photorefractive keratectomy: a two-armed cohort study

“…Further studies using different MMC concentrations and durations of laser exposure may provide further insights into this observation and the possible cause of the decline in the EC count. ECD is a benchmark index used to study the effects of various corneal procedures like collage cross-linkage, keratoplasty, and laser-assisted in situ keratomileusis (LASIK) on the EC status [25][26][27] . In these studies, surgical trauma indices temporarily decline in ECD.…”