Decontamination of Cadaver Corneas

Bacterial contamination of human corneas, in vivo and post mortem, was investigated. Bacterial samples were obtained by pressing small concave agar plates directly against the corneas. More colony forming units (C.F.U.) occurred in samples obtained from patients in general anesthesia than in samples obtained from healthy persons in local anaesthesia. The largest number of C.F.U. occurred post mortem. The number of C.F.U. obtained from cadaver corneas was not correlated to post mortem time. Rinsing with water removed 86% of the C.F.U. on cadaver corneas. Rinsing with water for 30 sec followed by 2 min treatment with 0.5% polyvinylpyrrolidone-iodine (PVP-I) and repeated rinsing removed 98% of the C.F.U. Epithelial or stromal lesions were not found after 2 min of exposure to 0.5% PVP-I.