Early Corneal Remodelling Following Topography-Guided Femtosecond LASIK: A Three-Month Retrospective Analysis

Abstract

Background: Topography-guided femtosecond LASIK (TG-Femto-LASIK) improves corneal shape uniformity while correcting refractive errors. Although visual and refractive outcomes have been widely reported, fewer studies have focused on corneal shape indices and ectasia-related safety parameters, which are essential for evaluating postoperative stability. This study aimed to assess three-month changes in corneal remodeling and safety markers following TG-Femto-LASIK. Methods: A retrospective study was conducted on 50 eyes that underwent TG-Femto-LASIK at the IIUM Eye Specialist Clinic. Preoperative and three-month postoperative values of keratometry (K1, K2), corneal astigmatism, and axial inferior–superior (I–S) index were compared using paired t-tests. Preoperative Randleman ectasia scores and postoperative residual stromal bed (RSB) thickness were assessed as safety parameters. Results were presented as mean ± standard deviation (SD), mean difference with 95% confidence intervals (CI), and p-values. Results: At three months, K1 decreased by 4.22 D (95% CI 3.85–4.59, p<0.001) and K2 by 3.55 D (95% CI 3.20–3.90, p<0.001). Corneal astigmatism reduced by 1.04 D (95% CI 0.65–1.42, p<0.001). The axial I–S index increased by 0.24 D (95% CI 0.07–0.41, p=0.006). Mean preoperative Randleman score was 2.12 ± 1.49; postoperative RSB averaged 346.8 ± 38.9 µm (range 281–449 µm). Conclusion: TG-Femto-LASIK effectively reshapes the cornea by significantly reducing keratometry and astigmatism while maintaining corneal symmetry within physiological limits. The minor increase in the I–S index remained below ectasia-suspect thresholds, and safety metrics—namely the Randleman score and RSB—confirmed that all procedures were performed within accepted biomechanical margins. These findings highlight TG-Femto-LASIK as a safe and effective procedure for early postoperative corneal stability.