Abstract
Purpose: :
DMEK is an exciting new frontier in EK technology, but further studies are required to establish a consistently safe and efficient method of tissue preparation. This work evaluates the endothelial cell loss resulting from two recently described methods of preparing endothelial tissue for DMEK procedures.
Methods: :
Two experienced DSEK and DALK surgeons and one DMEK-trained certified eye bank technician prepared 8.0 mm diameter DMEK discs. 23 grafts were prepared using the "Scuba" technique taught in DMEK training courses. 8 grafts were prepared by the "Big Bubble" technique recently put forth by Dr. Bussin, using a 27G needle to inject air beneath the endothelium of donor corneas placed on Barron suction trephines endothelial side up. Endothelial cell loss was determined in 6 Scuba grafts and 3 Big Bubble grafts by vital dye staining and computer digitized planimetry. Cell loss was compared between groups using an independent samples t-test.
Results: :
Mean cell loss was 26% for the Scuba technique (range 12.5% to 49%) and 23% for the Big Bubble technique (range 15% to 37%). The t-test showed no significant difference in cell loss between techniques (p=0.7). Vital dye staining revealed patterns of stretch lines and grasp point injuries resulting from the Scuba technique, and injection site damage resulting from the Big Bubble technique.
Conclusions: :
No significant difference was shown in terms of endothelial cell loss between the Scuba and Big Bubble techniques. However, both methods resulted in unacceptably high rates of cell damage and require further refining before becoming the new standard of care in endothelial keratoplasty.
Keywords: cornea: endothelium • cornea: basic science