Progressive Flattening after Corneal Collagen Crosslinking: A 10-Year Follow-Up

Abstract

Purpose: This study aimed to demonstrate the importance of long-term follow-up after corneal collagen crosslinking. Methods: This case report showed an intense progressive flattening of keratometric parameters in a patient without risk factors such as high maximum keratometry, thin cornea, uncontrolled ocular allergy, collagen, or rheumatologic diseases. Even with significant haze formation and progressive flattening, the patient exhibited progression after a long follow-up period. Results: The patient presented with grade 2 haze associated with progressive flattening of approximately 10 D in keratometric parameters (Kmax, K1, K2, and Kmean) during the first 5 years after surgery. Corneal opacity altered the minimum pachymetry reading on Pentacam to 265 microns. Anterior corneal follow-up optical coherence tomography revealed a thickness of 453 microns. The patient developed low visual acuity while wearing glasses. The scleral lens was fitted, allowing a visual acuity of 20/30, with satisfactory visual quality. Keratometric stability was observed between the fifth and tenth year. In the tenth year, the patient maintained haze, but there was a progression of 1.7 D in the Pentacam comparative map. Conclusions: Long-term monitoring after corneal crosslinking should be performed. Eyes with haze and intense progressive flattening may fail after a long period.