The 5-Year Results Of Corneal Collagen Crosslinking For Patients With Progressive Keratoconus: A Keratometric And Pachymetric Analysis

This study aimed to investigate the long-term effects of corneal collagen crosslinking (CXL) on keratoconus progression, focusing on the flattening of corneal cones in different locations and associated pachymetric changes over a 5-year period

Sussex Eye Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, United Kingdom

A retrospective analysis was conducted on 53 eyes of 53 patients diagnosed with progressive keratoconus who underwent epithelium-off CXL treatment between 2014 and 2019. Cone locations (central, paracentral, and peripheral) were determined using Pentacam HR Scheimpflug tomography. The CXL standard protocol involved riboflavin soaking and UV-A radiation. Follow-up included baseline, 1-year, and 5-year measurements of keratometry parameters and pachymetry. Statistical analysis included t-tests, correlation studies, and regression analysis.

The study demonstrated a significant reduction in keratometry values, with central, paracentral, and peripheral cones showing decreases of 2.8 D, 2.4 D, and 1.5 D, respectively, at the 5-year follow up. Pachymetric changes varied among cone locations, with peripheral cones exhibiting a decrease followed by an elevation, while central cones showed a consistent decrease. Paracenteral cones showed a decrease

in mean thinnest point thickness, which was followed by an increase above baseline. Correlation analysis revealed a strong positive correlation between preoperative and 5-year postoperative Kmax. Regression analysis suggested that preoperative Kmax was a significant predictor of postoperative cone flattening.

Corneal collagen crosslinking proved effective in halting keratoconus progression over a 5-year period, as evidenced by significant flattening of corneal cones. The study provides valuable insights into the long-term outcomes of CXL, emphasizing the importance of preoperative Kmax as a predictor for postoperative results.