Efficacy and safety of moxifloxacin as an additive in Optisol-GS a preservation medium for corneal donor tissue

PURPOSE: To assess the endothelial toxicity and the microbiological efficacy of moxifloxacin (250 μg/mL) as an additive to Optisol-GS®. METHODS: Five hundred nine donor rims were studied. One half of each donor rim was placed in standard Optisol-GS® and the other half of the rim in Optisol-GS® fortified with moxifloxacin (250 μg/mL). All rims were refrigerated for 24 hours at 3°C and placed in thioglycolate broth and incubated at 37°C for 7 days. One pair of donor buttons not used in transplantation stored in each solution was examined for endothelial changes by using electron microscopy (EM). A second pair of cornea buttons was examined for toxicity by endothelial staining with 0.3% trypan blue and 0.2% alizarin red. All endothelial cells that stained (nonviable cells) and nonstained cells (viable cells) were counted, and the ratio of nonviable cells was calculated. RESULTS: The rate of culture-positive donor rims in the Optisol-GS® group was 11.9% (61/509) and in the moxifloxacin-fortified Optisol-GS® media was 2.5% (13/509). The difference was statistically significant (P < 0.01; χ test). There was no difference in the cellular morphology of the button stored in moxifloxacin-fortified Optisol-GS® compared with Optisol-GS® using EM. In the bioassay, the rate of nonviable cells in the moxifloxacin-fortified media compared with the control media was nonsignificant (P > 0.05). CONCLUSION: Moxifloxacin (250 μg/mL) seems to be safe as an additive agent for cornea storage media. It significantly reduces the rate of positive rim cultures and shows no signs of endothelial cytotoxicity as viewed by EM and by a bioassay of trypan blue and alizarin red.