Quantifying the Impact of Uneventful LASIK on the Cornea

Abstract

This study investigates the changes in the optical properties of the cornea after laser in situ keratomileusis (LASIK) based on Scheimpflug light intensity distribution. Retrospective data from patients who had undergone uneventful LASIK surgery were eligible. Scheimpflug images obtained with the Pentacam (6.10r59) HR device prior to the LASIK treatment, 3 months afterwards and (in a subset of patients) 1 year after treatment were exported for analysis of corneal transparency in different depths and regions. Corneal segmentation and statistical modeling of the pixel brightness distribution were performed for each image. The intensity of the pixels corresponding to the central 8 mm of the cornea was statistically modeled using the Weibull function, yielding two derived parameters: the scale parameter (α, representing corneal transparency) and the shape parameter (β, representing corneal tissue homogeneity). Additionally, the same analysis was carried out within the flap area (central 3.5 mm). A total of 90 patients were included. No statistically significant changes were observed in parameter α (p > 0.05). Parameter β exhibited significantly lower values at both the 3-month follow-up (in the anterior cornea and stroma, p < 0.05) and 1-year follow-up (in all depths, p < 0.05). In conclusion, the cornea demonstrated significantly lower tissue homogeneity following uncomplicated LASIK surgery, but overall corneal transparency remained unchanged.