Effects of Eye Bank Donor Age Expansion on Corneal Endothelial Cell Density and Surgeon Tissue Acceptance

Abstract

Purpose : To investigate the effects of expansion in eye bank donor age (now including donors aged 76-80) on corneal endothelial cell density (ECD) and surgeon acceptance rate of donated tissues.

Methods : This is a single-site, retrospective study of 25,969 corneas from Eye Bank donors in 2018 - 2022 between the ages of 2 - 75 years (n=25,558) and 76 - 80 years (n=411). The donor age limit was increased to 80 years at the beginning of 2022. Donor characteristics, endothelial cell density, and acceptance of tissues for use in surgery were compared between age groups stratified by five-year intervals. Fisher's Exact Test and Mann-Whitney U-tests were used to compare between each group of patients.

Results : The increase in donor age limit allowed 411 more cornea donations which resulted in 208 more surgeries. The average ECD in donors between the ages of 71 - 75 was 2,350 ± 13 cells/mm2 and 2226 ± 52 cells/mm2 in the donors between the ages of 76 - 80, with a lower ECD in the age group of 76-80 than 71-75 (-124 cells/mm2 (95% CI=64-181, p<0.001) (Table). 38 % of corneas from donors between the ages of 71 - 75 were not accepted for transplant while 48 % of corneas from donors between the ages of 76 - 80 were not accepted for transplant, an increase of 10% (95% CI=4.9-15.1, p value= <0.001)(Figure). Although ECD is shown to decrease with each increase in donor group age (Table), corneas from the older donor group (aged 76-80) have arguably clinically insignificant differences in cell densities when compared to donors from the younger group (aged 71-75). Some reasons cited for not accepting tissue for transplant included scarring, low endothelial cell count, and indication of ocular disease.

Conclusions : Corneas from donors of older ages are significantly less likely to be accepted for transplant. Age bias by surgeons against older corneas is a possible reason for this finding that should be further explored.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Figure: Corneal endothelial cell counts and percent of corneas accepted for surgery per donor age group.

 

Table: Corneal endothelial cell counts, percent of corneas accepted for surgery, and # of eyes donated per age group.