PURPOSE: To assess whether the biological quality of corneoscleral tissue dissected in situ is, after organ culture, comparable to that harvested after enucleation. METHODS: Corneoscleral discs were prepared from 23 donor eyes, either after enucleation, under laminar flow conditions (right eyes; group 1) or by direct excision in situ (left eyes; group 2). Endothelial cell counts were made and the degree of tissue contamination assessed both prior to and upon termination of organ culture. RESULTS: Microbial growth was found in 12/22 conjunctival swabs collected from group 1 eyes and in 14/22 of those obtained from group 2 globes (p = 0.76). Bacterial growth was detected in four primary culture media, two from each group, at low colony densities. No significant difference in endothelial cell counts were encountered between the two groups, either immediately after dissection [group 1: 2940 +/- 308 (2100-3500) c/mm2; group 2: 2947 +/- 345 (2200-3700) c/mm2; p = 0.945] or upon termination of organ culture [group 1: 2646 +/- 321 (1895-3200); group 2: 2723 +/- 312 (2100-3650); p = 0.413]. CONCLUSION: Dissection of corneoscleral discs in situ may serve as an alternative to the conventional technique if consent is obtained to remove only the cornea. The risk of contamination is no higher and endothelial cell viability no lower than in tissue derived from enucleated globes, provided that the excision is performed by a skilled surgeon and a rigorous disinfection protocol is instigated.
PURPOSE: To assess whether the biological quality of corneoscleral tissue dissected in situ is, after organ culture, comparable to that harvested after enucleation. METHODS: Corneoscleral discs were prepared from 23 donor eyes, either after enucleation, under laminar flow conditions (right eyes; group 1) or by direct excision in situ (left eyes; group 2). Endothelial cell counts were made and the degree of tissue contamination assessed both prior to and upon termination of organ culture. RESULTS: Microbial growth was found in 12/22 conjunctival swabs collected from group 1 eyes and in 14/22 of those obtained from group 2 globes (p = 0.76). Bacterial growth was detected in four primary culture media, two from each group, at low colony densities. No significant difference in endothelial cell counts were encountered between the two groups, either immediately after dissection [group 1: 2940 +/- 308 (2100-3500) c/mm2; group 2: 2947 +/- 345 (2200-3700) c/mm2; p = 0.945] or upon termination of organ culture [group 1: 2646 +/- 321 (1895-3200); group 2: 2723 +/- 312 (2100-3650); p = 0.413]. CONCLUSION: Dissection of corneoscleral discs in situ may serve as an alternative to the conventional technique if consent is obtained to remove only the cornea. The risk of contamination is no higher and endothelial cell viability no lower than in tissue derived from enucleated globes, provided that the excision is performed by a skilled surgeon and a rigorous disinfection protocol is instigated.