Corneal crosslinking (CXL) has been growing in popularity these last 15 years as doctors use the technique to manage keratoconus and other ectasia-related conditions, such as pellucid marginal degeneration, Terrien’s marginal degeneration and post-LASIK ectasia. The mechanism of the CXL procedure relies on oxygen to react with riboflavin. But the process itself can also, briefly, reduce the oxygen levels in the eye. When the procedure is performed in a low-oxygen environment, the patient can experience a significant decrease in biomechanical rigidity compared with normal oxygen levels. This can halt the photopolymerization process that CXL depends on.

To combat this, a Chinese research team evaluated the impact of increasing oxygen concentrations during ultraviolet A (UVA) irradiation and found that this additional step can improve the procedure’s efficacy.

The investigators reviewed 60 freshly enucleated porcine eyes with a central corneal thickness (CCT) of 800±100mm, and divided the eyes into three groups: one subjected to conventional CXL, one subjected to a high-oxygen environment during UVA irradiation and a third untreated control group.

The team says their results showed that increasing oxygen concentration around the cornea during UVA irradiation may improve the efficacy of conventional CXL altogether.

Wang J, Wang L, Li Z, et al. Corneal biomechanical evaluation after conventional corneal crosslinking with oxygen enrichment. Eye Contact Lens. August 13, 2019. [Epub ahead of print].