The toxic effect of different concentrations of povidone iodine on the rabbit's cornea

Objectives: To investigate the effects of polyvinylpyrrolidone (i.e., povidone) iodine (PVP-I) in different concentrations on the rabbit's cornea. Methods: PVP-I in various concentrations was instilled into the conjunctival sac and injected into the anterior chamber independently. The toxicity to the cornea was assessed by fluorescence dye, specular microscopy, and corneal pachymetry. Results: After conjunctival sac PVP-I instillation, severe epithelial damage was observed at the concentrations of 5.0% and 2.5%. After anterior chamber PVP-I injection, significant corneal edema was observed at the concentrations of 2.0% and 1.5%. Conclusions: It can be safe and feasible to use 0.5% or 1.0% concentrations of PVP-I in conjunctival sac instillation for preoperative antisepsis.