Safety and efficacy of quercetin as an alternative to riboflavin in collagen cross-linking treatment.

PURPOSE: To evaluate the safety and efficacy of quercetin as an alternative to riboflavin in collagen cross-linking (CXL) treatment.

METHODS

Australia-New Zealand rabbits (n=60) were divided into four groups: a control group (C group; no UVA exposure), a Tween 20 buffer group (T group; UVA irradiated), a riboflavin group (R group; UVA irradiated with riboflavin), and a quercetin group (Q group; UVA irradiated with quercetin). The corneal tissues were analyzed histologically and biomechanically on days 7 and 42 post-treatment.

RESULTS

The biomechanical tests demonstrated a 50% increase in Young's modulus and a 21% increase in tensile strength in the R group compared to controls (P<0.05), confirming significant corneal stiffening. In contrast, the Q group showed an 18% increase in Young's modulus, but this was not statistically significant compared to controls (P>0.05). Histological analysis revealed no inflammation, corneal edema, or endothelial damage in any group. Keratocyte apoptosis was detected in the anterior stroma of the R and Q groups at day 7, with repopulation occurring by day 42.

CONCLUSION

While quercetin demonstrated some biomechanical effects; its impact on corneal stiffening was significantly lower than that of riboflavin, indicating its inefficacy as a photo-induced cross-linking agent.