Quantitative and Qualitative Differences in Endothelial Cell Loss Between Endothelium-In Versus Endothelium-Out Loading in Descemet Membrane Endothelial Keratoplasty.

ABSTRACT

PURPOSE: This study compares endothelial cell loss (ECL) between donor grafts loaded in the Geuder Glass Cannula and the Coronet EndoGlide made specifically for Descemet membrane endothelial keratoplasty (DMEK). METHODS: Prestripped tissues using the submerged cornea using backgrounds away (SCUBA) technique were obtained from an eye bank. Donor grafts were loaded with the Geuder Glass Cannula or Coronet DMEK EndoGlide. Grafts were then ejected directly onto a glass slide, stained, and imaged with confocal fluorescent microscopy. Trainable Fiji (ImageJ) segmentation software was used to quantify ECL. RESULTS: Twenty-three total tissue samples were tested. Eleven grafts were loaded using the Geuder, and 12 were loaded with the Coronet. Preloading graft endothelial cell density was comparable between Geuder (2436 ± 581 cells/mm) and Coronet (2577 ± 483 cells/mm) groups with P = 0.56. Other baseline characteristics including donor age and time from death to loading were comparable (P = 0.73 and P = 0.66, respectively). Average ECL was 11.3% ± 3.0% in the Geuder group versus 7.2% ± 7.0% in the Coronet group and not significantly different (P = 0.07). When observing patterns of cell loss, grafts loaded in the Coronet DMEK EndoGlide resulted in more focal forceps grabs and trifold patterns. Grafts loaded with the Geuder Glass Cannula yielded more diffuse stippled stress lines. CONCLUSIONS: Our results suggest comparable ECL between Geuder (endothelium-out) and Coronet (endothelium-in) DMEK EndoGlide tissue injection techniques. Patterns of ECL in the Coronet group correlated with forceps grabs, but this study suggests that additional manipulation of tissue does not result in higher ECL.