Influencing Factors in Corneal Densitometry Recovery After Accelerated Cross-Linking for Keratoconus

This study examines corneal densitometry recovery and influencing factors following accelerated corneal cross-linking (CXL) for progressive keratoconus. Corneal densitometry, measured using Scheimpflug tomography, provides an objective assessment of corneal clarity, especially in tracking the resolution of postoperative haze. We conducted a retrospective case-control analysis of 24 patients (31 eyes) who underwent CXL with 0.25% riboflavin and 18 mW/cm² irradiation between 2021 and 2023. Variables included patient age, maximum keratometry (K _max), central corneal thickness (CCT), and demarcation line depth (DLD), defined as the depth of the CXL region. Results revealed a significant increase in densitometry values across most corneal zones at 1-month postoperation, followed by a gradual return to baseline by 12 months. Notably, younger patients exhibited a faster recovery, with mean densitometry values returning to baseline in 11.4 months compared to 14.9 months in older patients (p=0.02). Similarly, corneas with deeper DLDs demonstrated faster densitometry recovery, suggesting a potentially more efficient corneal remodeling process. Additional analysis indicated a trend toward higher densitometry values in shallower DLDs at 1 month, although this difference was not statistically significant. These findings support the use of densitometry as a reliable measure of post-CXL healing. While DLD depth and patient age were associated with a faster recovery, they did not directly predict final corneal clarity. Our study suggests that factors such as age and DLD depth should be considered in patient prognosis, although further research is needed to confirm these findings across varying CXL protocols.