Table of Contents
Comparison of Endothelial Cell Measurements by Two Eye Bank Specular Microscopes
Khoa D. Tran, PhD; Jameson Clover, CEBT; Kelly Odell, BS; Winston Chamberlain, MD, PhD, and Christopher G. Stoeger, MBA
Cornea, Endothelial cell density, Specular microscope, Eye bank, Equipment qualification
Purpose: To compare endothelial cell measurements between a new specular microscope, the Konan CD-15/CellChekD+, and its predecessor, the Konan EKA-10/EB10.
Methods: Specular images and cell measurements were obtained on both systems by the same technicians. In one assay, the same cells were imaged and measured on both platforms. Additional corneas, including eye bank processed DMEK and DSAEK tissues, were analyzed using the standard method of acquiring three random specular images and counting 50-80 cells per image (>120 cells were measured per cornea). For all experiments, endothelial cell densities (ECD) were obtained manually using the center method and cell measurements were calculated using software included with each system.
Results: A total of 99 corneas from 58 donors were examined. Random sampling of 50 donor corneas revealed an overall average difference of 34 cells/mm2 (p=0.14) between the two
systems. In the direct comparison assay where the same cells were selected, the overall average difference in ECD measurements between the two systems was 18 cells/mm2 (p=0.17, R2=0.98, p<0.001). Roughly 1-1.5% of the differences in ECD measurements between individual pairs of measurements may be attributed to the input error of the center method on both systems. ECD measurements for eye bank processed DMEK and DSAEK tissues differed by 14 and 36 cells/mm2, respectively (p<0.05).
Conclusions: Comparison of endothelial cell measurements between the two systems revealed insignificant differences. ECD, HEX, and CV values obtained from the two systems can be used
interchangeably, and should have no negative impact on tissue evaluation as well as on-going basic and clinical research.