Comparing Different Decontamination Procedures in Harvesting Human Donor Cornea

Abstract

Purpose: 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.

Materials and methods: 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.

Results: 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.

Conclusions: 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.

Keywords: Corneal transplantation; decontamination; enucleation; eye bank; povidone iodine.