Preparation of donor corneas: a study of the endothelial population.

Purpose: To quantify the endothelial damage in corneal rim excisions prepared in different ways.

Methods: From the Imola branch of Eye Bank of Emilia Romagna, 24 corneal rim excisions which belonged to 12 pairs of enucleated eye globes were selected. The endothelial mortality was quantified by Trypan blue staining and counting the endothelial cells in a central area of about 5 square mm of each cornea. The mate corneas of each pair were prepared in two different ways: one with an epithelium-endothelium cut using a Hanna trephine with an artificial chamber and the other with an endothelium-epithelium cut using a Hanna trephine with punch. After the cut the endothelium was studied again in the same way as described above.

Results: The cell mortality in the corneas before and after the epithelium-endothelium cut using the artificial chamber was increased by 0.9% and the percentage of endothelial loss was increased by 3.9+/-6.8%. In the corneas prepared with endothelium-epithelium cut using a punch the mortality before and after the cut increased by 8.8% and the percentage of endothelial loss was 20.7+/-10.9%.

Conclusions: The authors found that in terms of endothelial mortality and endothelial cell density there is less damage to the endothelial population using the epithelium-endothelium cut as compared to the endothelium-epithelium cut.