Are Polymegethism, Pleomorphism, and “Poor Swelling” Valid Discard Parameters in Immediate Postmortem Evaluation of Human Donor Corneal Endothelium?

Abstract

To study the validity of endothelial polymegethism, pleomorphism, and "poor swelling" as tissue discard parameters in the immediate postmortem evaluation of human donor corneal endothelium. We retrospectively evaluated the quality of the endothelium at first and second evaluations for all processed corneas exhibiting moderate polymegethism, pleomorphism, or "poor swelling" in our eye bank over a 5-year period. Out of 2008 eyes qualifying for our study, 422 corneas (21%) showed polymegethism, pleomorphism, or poor swelling at the first tissue evaluation immediately after excision of the corneoscleral button. In 363 (86%) of these corneas, a normal endothelial mosaic was observed at the second tissue evaluation after 7 to 21 days of organ culture, whereas only 59 (14%) still showed persistent polymegethism, pleomorphism, or "poor swelling" at that time point. A recovery of normal endothelial cell mosaic and "normal swelling" at the second evaluation suggests that cellular contour parameters do not relate to tissue viability, but rather to a cellular stress reaction. If so, the validity of endothelial cellular contour morphology as an early parameter in assessing the suitability of a donor cornea for transplantation may be reconsidered.