Seven-day storage of pneumatically dissected Descemet's endothelial grafts with and without Dua's layer

To evaluate the efficacy of big-bubble (BB) technique in separating Dua's layer together with the Descemet's membrane endothelial (DE) graft and the effect of 7-day storage of the prepared tissues on the endothelial cells.

This is an experimental study in which 21 human corneo-scleral tissues unsuitable for transplantation were used. Grafts were mounted on artificial chamber; epithelial side-up with BB technique was used to detach the DE graft. The resultant tissues were stored in tissue culture medium for 7 days. Dua's layer presence, endothelial cell density (ECD), endothelial cell loss and viability were assessed after the dissection and at 7 days after storage.

Complete detachment of DE grafts was achieved in 20 cases (95.24%). Histological analysis revealed Dua's layer presence in 14 cases (70%). The mean ECD for the corneas before dissection was 2375 ± 338 cells/mm(2) with significant reduction to 2200 ± 319 cells/mm(2) (p < 0.00001) with endothelial cell loss of 7.3 ± 3.5% and non-viable cells of 6.5 ± 2.5% at the end of the 7-day storage. On comparing the dissected DE grafts with Dua's layer versus those without at 1 day after dissection and at 7 days after storage, we found no statistically significant changes in endothelial cell loss (p = 0.387; p = 0.836 respectively) and non-viable cells percentage (p = 0.180; p = 0.260, respectively).

Big-bubble technique is reproducible in dissecting DE grafts with minimal damage to the endothelial cells. The percentage of endothelial cell loss and non-viable cells is similar in the DE grafts with/without Dua's layer after 7-day storage.