PURPOSE: To evaluate a single eye bank's measurement of endothelial cell density (ECD) of Descemet membrane endothelial keratoplasty (DMEK) grafts before and after preparation using 2 separate counting methods. METHODS: A series of 60 donor tissues were prepared for DMEK surgery. One to 4 specular images of the central endothelium were taken both before and after preparation, and ECDs were evaluated for a total of 345 unique images. Images were then masked and provided to the Cornea Image Analysis Reading Center (CIARC) for independent analysis. RESULTS: Before preparation, average eye bank-determined ECD with the center method was 2678 ± 259 cells/mm and was 2599 ± 280 cells/mm CIARC-determined by the variable frame method (P < 0.001, n = 176). After preparation, eye bank-determined ECD was 2719 ± 265 cells/mm and CIARC-determined ECD was 2615 ± 344 cells/mm (P < 0.001, n = 169). The difference in ECD before and after DMEK preparation was not found to be statistically significant when evaluated using either analysis method (P = 0.19; P = 0.64) before and after preparation, respectively. CONCLUSIONS: Although the absolute ECD value may differ by the analysis method statistically, pre- and post-DMEK preparation ECDs did not significantly change by either analysis method. Other methods such as vital staining to assess tissue damage after preparation in conjunction with specular microscopy are suggested.
PURPOSE: To evaluate a single eye bank's measurement of endothelial cell density (ECD) of Descemet membrane endothelial keratoplasty (DMEK) grafts before and after preparation using 2 separate counting methods. METHODS: A series of 60 donor tissues were prepared for DMEK surgery. One to 4 specular images of the central endothelium were taken both before and after preparation, and ECDs were evaluated for a total of 345 unique images. Images were then masked and provided to the Cornea Image Analysis Reading Center (CIARC) for independent analysis. RESULTS: Before preparation, average eye bank-determined ECD with the center method was 2678 ± 259 cells/mm and was 2599 ± 280 cells/mm CIARC-determined by the variable frame method (P < 0.001, n = 176). After preparation, eye bank-determined ECD was 2719 ± 265 cells/mm and CIARC-determined ECD was 2615 ± 344 cells/mm (P < 0.001, n = 169). The difference in ECD before and after DMEK preparation was not found to be statistically significant when evaluated using either analysis method (P = 0.19; P = 0.64) before and after preparation, respectively. CONCLUSIONS: Although the absolute ECD value may differ by the analysis method statistically, pre- and post-DMEK preparation ECDs did not significantly change by either analysis method. Other methods such as vital staining to assess tissue damage after preparation in conjunction with specular microscopy are suggested.
Authors: Beth Ann Benetz; Christopher G Stoeger; Sanjay V Patel; Robert C OʼBrien; Loretta B Szczotka-Flynn; Allison R Ayala; Maureen G Maguire; Harry J Menegay; Peter Bedard; Jameson M Clover; Pankaj C Gupta; Kristen E McCoy; Jonathan C Song; Jonathan H Lass Journal: Cornea Date: 2019-04 Impact factor: 3.152