Corneal Cross-Linking and Transplantation Trends for Keratoconus in Portugal: A Multicenter Retrospective Analysis
DOI:
https://doi.org/10.48560/rspo.43723Keywords:
Cornea, Corneal Cross-Linking, Corneal Transplantation, KeratoconusAbstract
INTRODUCTION: Keratoconus (KC) is a corneal ectatic disorder characterized by progressive thinning and protrusion. Approximately 20% of KC patients eventually require corneal transplantation. Corneal cross-linking (CXL) has proven effective in halting disease progression, potentially preventing or delaying the need for transplantation. This study aims to evaluate whether current patterns of CXL implementation have impacted the number of corneal transplants in KC patients in Portugal.
METHODS: Multicentric retrospective study conducted at three Portuguese tertiary centers. Data regarding corneal transplantations performed between 2011 and 2024 were collected from the Eye Bank registries of the participating centers. Data on CXL procedures performed during the same period were retrieved from medical records. Temporal trends in corneal transplantation were analyzed in relation to the introduction and subsequent adoption of CXL.
RESULTS: Between 2011 and 2024, a total of 5595 corneal transplants were performed across the three centers. Of these, 864 (15.4%) were for KC, including 542 (62.7%) penetrating keratoplasties (PK) and 322 (37.3%) deep anterior lamellar keratoplasties (DALK). During the same period, 397 CXL were performed. Patients undergoing CXL were significantly younger than those receiving keratoplasty (21.1±2.5 vs 34.9±2.1 years, p<0.001). Since 2018, the annual number of CXL procedures increased significantly (7.3±6.1 to 49.4±12.2, p<0.001), while transplants for KC showed a non-significant decline (64.7±10.1 to 58.7±16.5, p=0.427). No statistically significant association was found between CXL activity and keratoplasty rates, although a negative trend was observed. The proportion of CXL procedures relative to KC-related transplants increased significantly over time (p<0.001). Only one patient who underwent CXL subsequently required corneal transplantation.
CONCLUSION: CXL use has increased substantially in recent years, reinforcing its role as an effective treatment to halt KC progression. However, this wider availability has not yet translated into a measurable reduction in the overall burden of KC requiring transplantation. Early diagnosis and intervention, as well as the standardization of follow-up and treatment guidelines, are essential to understand and enhance the preventive benefit of CXL at the healthcare system level.
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