Abstract
Purpose: :
To evaluate tissue damage when preparing DMEK donor tissue and compare the rates of tissue wastage using 2 different techniques of harvesting: the "Big Bubble" versus "SCUBA" technique.
Methods: :
A surgeon experienced in lamellar surgical techniques prepared 8.0 mm diameter DMEK discs using the "Big Bubble" technique by utilizing a 27G needle to inject air beneath the endothelium of donor corneas placed on Barron suction trephines endothelial side up (n=10). These corneas were then compared to 8.0 mm diameter DMEK discs harvested by a similarly skilled surgeon using an alternative "SCUBA" technique that has been taught in various DMEK courses (n=23). A total of 16 donor bank eyes (8 for each method) were used as practice before commencing the experiments. Rates of total tissue destruction in both groups were recorded and analyzed. Tissue wastage rates were compared with chi-square analysis.
Results: :
For the 10 cases of "Big Bubble" prepared tissue, 30% (3/10) of tissues were so damaged during harvesting that they were deemed to be non-transplantable in comparison to a 26% (6/23) tissue wastage rate among corneas prepared for DMEK using the "SCUBA" technique (p=0.219).
Conclusions: :
DMEK surgery is an exciting innovation in the evolution of endothelial keratoplasty and with this new direction, multiple strategies for harvesting donor tissue have been described. This initial report shows that tissue wastage rates from the newer "Big Bubble" technique is at least comparable to the currently taught "SCUBA" technique without any statistically significant difference; however, the rates are still very high (>25%), suggesting DMEK donor preparation techniques still need to be refined before this procedure can become a safe and consistent alternative to the current DSAEK surgery.
Keywords: cornea: clinical science • cornea: endothelium • cell survival