Age Impact on Corneas Stored with Organ Culture Media in New South Wales Tissue Banks

Abstract

Purpose : Low endothelial cell density (ECD) and poor cell viability remains one of the leading causes for withholding corneas stored in Eye Banks from surgical use. The purpose of this study was to determine the influence of donor age upon corneal ECD and cell viability for corneas stored in organ culture media (OCM).

Methods : Donor corneas stored in OCM at the New South Wales Tissue Banks between April 1, 2014, and December 31, 2018 were reviewed retrospectively. Corneas were divided into 5 age groups: age ≤40 years; age 41-50 years; age 51-60 years; age 61–70 years and age ≥71 years. Pearson’s correlation coefficient was used to investigate linear relationships across age, ECD, cell viability and endothelial cell loss. Further statistical analysis was performed using a generalized linear model to adjust for other factors studied.

Results : A total of 3392 corneas were included in this analysis. Of these, 4.3% (145/3392) were unsuitable for surgical use due to either low ECD (<2200 cells/mm²), or low cell viability (≤70%), or both. The mean donor age at death was 62.59±14.14 years (range from 2 to 101 years). At the end of storage, the mean ECD was 3012.18±416.39 cells/mm² and the mean viability was 94.74±6.28%.

A significant positive correlation was observed between final ECD and viability (r=0.596, p < 0.01). There was also a negative relationship between initial ECD and final cell loss (r=-0.60, p<0.01). Younger corneas had significantly lower cell viability, lower ECD, and greater cell loss at the end of storage in comparison to corneas with age over 70 (p < 0.05). Furthermore, corneas stored for up to 10 days demonstrated significantly higher cell viability and ECD than those corneas stored for greater than 20 days (p<0.001). No correlation was found between circulatory-standstill-to-preservation time and cell viability (p=0.673) or final ECD (p=0.873).

Conclusions : The results from this study show that older corneas have less endothelial cell loss and greater cell viability during organ culture storage. This may be due to younger corneas having a generally higher metabolic state, which during storage, results in a lack of endothelial nutrition. The corneas that are stored longer in OCM have overall greater cell loss and lower cell viability, suggesting that there is need to use the storage tissues early once they have become available. Further study is required to investigate the underlying mechanism.

This is a 2020 ARVO Annual Meeting abstract.