What question did this study set out to answer?

This research aims to evaluate the changes in corneal biomechanics and epithelial thickness in high myopia patients following LASIK, particularly in those with myopic regression.

March 30, 2026Open Access

Changes in Corneal Biomechanics and Epithelial Thickness in High Myopia Over −8.00D with/without Myopic Regression After Femtosecond Laser-Assisted in Situ Keratomileusis

Key Points

This research aims to evaluate the changes in corneal biomechanics and epithelial thickness in high myopia patients following LASIK, particularly in those with myopic regression.
Retrospective case-control design involving thirty-nine patients undergoing FS-LASIK.
Patients were categorized into myopic regression and normal groups based on refractive status after one year.
Comparative analysis of visual outcomes, refraction, topography, epithelial thickness, and biomechanics pre- and post-surgery.
Ambrosio relational thickness (ARTh) was significantly lower in the regression group at 3, 6, and 12 months post-surgery.
The stiffness parameter A1 was smaller in the regression group at 6 and 12 months after surgery.
Corneal epithelial thickness showed a significant negative correlation with refractive error at 12 months, particularly in the central zone.

Abstract

Purpose: To compare the changes in corneal biomechanics and epithelial thickness after femtosecond laser-assisted in situ keratomileusis (FS-LASIK) in high myopia over -8.00D patients with and without myopia regression.Methods: This retrospective case-control study included thirty-nine patients.Based on refractive status at one year after surgery, patients with a myopic shift 1.00 D were classified as the myopic regression group (R group, 33 eyes), while the remaining patients were classified as the normal group (N group, 42 eyes).Preoperative and postoperative visual outcomes, refraction, topography, corneal epithelial thickness, and corneal biomechanics were compared.Results: Ambrosio relational thickness to the horizontal profile (ARTh) at 3, 6, and 12 months postoperatively was significantly smaller in the R than in the N group, with mean differences of -9.75 (95% confidence interval (CI): -18.44 to -1.04), p= 0.029; -12.23 (95% CI: -20.02 to -4.42), p= 0.003; and -9.47 (95% CI: -16.86 to -2.08), p= 0.013, respectively.Meanwhile, the stiffness parameter A1 (SP-A1) at 6 and 12 months after surgery was smaller in the R than in the N group, with mean differences of -6.62 (95% CI: -12.85 to -0.37), p= 0.038 and -7.26 (95% CI: -13.79 to -0.71), p= 0.030, respectively.The postoperative changes in SP-A1 at 6 and 12 months were significantly larger in the R group than in the N group (6.47, 95% CI: 1.04 to 11.91, p= 0.020; and 5.96, 95% CI: 0.37 to 11.52, p= 0.037, respectively).In addition, corneal epithelial thickness (CET) in different zones showed a significant negative correlation with refractive error at 12 months after surgery, with correlation coefficients ranging from -0.55 to -0.32 (all p< 0.05, with the central zone showing p< 0.001).Conclusion: Ultra-high myopic patients with post-FS-LASIK regression have poorer corneal biomechanics and greater central epithelial thickening, highlighting these factors as key susceptibility features for refractive instability.Early assessment of these parameters may help identify at-risk patients and guide personalized management to improve long-term outcomes.

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Cite This Study

Shao et al. (Sun,) studied this question.

synapsesocial.com/papers/69ca12d4883daed6ee0950d7 https://doi.org/https://doi.org/10.2147/opth.s586339

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