Official websites use. Share sensitive information only on official, secure websites. Aim: To examine the differences in manual endothelial cell counting methods in French eye banks and to analyse whether these differences could explain some substantial discrepancies observed in endothelial cell density ECD for corneas made available for transplant.
Methods: A questionnaire was sent to the 22 eye banks asking for details of the technical features of the light microscopes used, the microscope calibration, strategy for cell counting, the technical staff, and the method of presenting endothelial data. In five of these cases, the corrected ECD was lower than estimated on initial count. Conclusions: Lack of microscope calibration appears to be the leading cause of variance in ECD estimates in French eye banks.
Other factors such as differences in counting strategy, the evaluation of smaller numbers of cells, and the different extent of experience of the technicians may also contribute to intraobserver and interobserver variability.
Further comparative studies, including cross checking and the outcome of repeated counts from manual methods, are clearly needed with cross calibration to a computer based image archiving and analysis system.
An assessment of endothelial cell density ECD after corneal storage forms the main basis for selection and delivery of corneas by eye banks for transplant purposes.
