Comparison of dyes for cataract surgery. Part 1: cytotoxicity to corneal endothelial cells in a rabbit model

Abstract

The authors experimentally evaluated the corneal endothelial cytotoxicity of dyes used for capsule staining in cataract surgery. Cultured endothelial cells of New Zealand rabbits were exposed for 1 minute to various concentrations of one of the following dyes: indocyanine green (ICG), methylene blue (MB), gentian violet (GV), trypan blue (TB), and fluoresce in sodium (FS). The effect of longer exposure (up to 10 minutes) to ICG 0.25% was also investigated. The degree of cell damage was determined by in vitro staining with TB and comparison with results in a control group. Indocyanine green 0.25%, MB 0.20%, GV 0.01%, TB 0.40%, and FS 10% did not induce considerable damage to endothelial cells. Significant cytotoxicity was observed with the following or higher dye concentrations: ICG 0.50%, MB 0.50%, and GV 0.10%. Exposure to ICG 0.25% for 1 to 10 minutes showed a trend toward cytotoxicity after 10 minutes. On transmission electron microscopy, corneal endothelial cells that had been exposed to 0.50% ICG showed remarkable organelle swelling and disruption, electron-dense granules, and cell lysis. The authors conclude that 1 minute of exposure to ICG 0.25%, MB 0.20%, GV 0.01%, TB 0.40%, and FS 10% appears to be safe as determined by no cytotoxic effects on rabbit corneal endothelial cells in culture.—Michael D. Wagoner