The effect of collagen cross-linking procedure on the material of intracorneal ring segments.

PURPOSE: To assess the potential impact of corneal crosslinking treatment (365 nm ultraviolet (UV)A irradiation with riboflavin) on the material properties of Intracorneal Rings Segments (ICRS).

MATERIALS AND

METHODS

Material properties were studied using FT-IR spectroscopy and UV-Vis spectroscopy. Rings were examined: (1) after installation of riboflavin solution, (2) after irradiation with UV-A light and (3) after instillation of riboflavin solution followed by instillation and coeval irradiation. The experiments followed the standard corneal cross-linking (CXL) protocol of corneal crosslinking treatment.

RESULTS

After instillation of riboflavin solution, a permanent intense yellow staining of the samples was observed. UV-Vis spectroscopy confirmed that a certain amount of riboflavin solution was absorbed into the samples after CXL procedure. FT-IR spectroscopic analysis showed alterations in the spectra of ICRS mainly at the 2800-3200 cm(-1) spectral region [modification in band intensities of CH(2) (2925 cm(-1)) and CH(3) (2950 cm(-1))].

CONCLUSIONS

Our results suggest crosslinking reaction in ICRS material. This should be taken into consideration prior to any CXL treatment of post ICRS-implanted cornea.