Comparing Different Decontamination Procedures in Harvesting Human Donor Cornea

To evaluate the effects of current hygiene standards for the enucleation of postmortem eyes by investigating the number of microorganisms during subsequent steps of decontamination and tissue processing.

This prospective, non-randomized cohort study includes 184 postmortem eyes of 92 human donors. Enucleation was performed, according to an ophthalmic surgical procedure. Two groups were generated as follows: right eyes were allocated to group A, left eyes were allocated to group B. In group A, a mucosal disinfectant was used accessorily. Conjunctival smears were taken to examine germ load in both groups before any intervention, in group A after mucosal disinfection, in both groups after transportation of the whole globes in transport fluid, and in both groups after a bath in 0.75% povidone iodine solution for at least 3 minutes just before preparation of the corneoscleral disc. Smears were sent to the local microbiologic laboratory in an aseptic package for testing.

All smears showed multiple contaminations (n = 184/184 eyes) before treatment with povidone iodine solution. Contamination was in both groups significantly prevented using the treatment strategy of an at least 3-minute bath in 0.75% povidone iodine solution (n = 1/184 eyes; p < 0.01) As a side effect, almost every eye of group A and none of group B showed brown iodine staining corresponding to corneal epithelial erosion.

An aseptic setting for donor enucleation similar to a surgical procedure seems not to influence the outcome of germ colonization. The most effective step to decontaminate donor eyes is to use 0.75% povidone iodine solution for at least 3 minutes.