All content on Eyewiki is protected by copyright law and the Terms of Service. This content may not be reproduced, copied, or put into any artificial intelligence program, including large language and generative AI models, without permission from the Academy. Corneal collagen crosslinking CXL is a minimally invasive procedure used to prevent progression of corneal ectasia such as keratoconus and post-LASIK ectasia.
Cross-linking of collagen refers to the ability of collagen fibrils to form strong chemical bonds with adjacent fibrils.
In the cornea, collagen cross-linking occurs naturally with aging due to an oxidative deamination reaction that takes place within the end chains of the collagen. It has been hypothesized that this natural cross-linkage of collagen explains why keratectasia corneal ectasia often progresses most rapidly in adolescence or early adulthood but tends to stabilize in patients after middle-age.
While crosslinking tends to occur naturally over time, there are other pathways that may lead to premature crosslinking. Glycation refers to a reaction seen predominantly in diabetics that can lead to the formation of additional bonds between collagen.
In the pathway most relevant to this topic, oxidation has been shown to be able to trigger corneal crosslinkage through the release of oxygen free radicals. The bases for the currently employed corneal collagen cross-linking techniques were developed in Europe by researchers at the University of Dresden in the late s.
