Descemet Membrane Endothelial Keratoplasty: Comparison of Endothelial Cell Loss of Re-Bubbled Donor Grafts Versus Grafts Not Re-Bubbled

Sunday, April 19, 2015: 4:16 PM
Room 5A (San Diego Convention Center)
Mark A. Terry, MD
Zachary M. Mayko, MS
Christopher S. Sales, MD, MPH
Michael D. Straiko, MD

Purpose
To determine if the endothelial cell loss postop is different between Descemet membrane endothelial keratoplasty (DMEK) grafts that received an injection of air (re-bubble) post op compared to those grafts that did not.

Methods
Single center, single standardized technique of DMEK surgery performed for Fuchs’ dystrophy. (glass injector, SF6 gas bubble, eye bank pre-stripped tissue) All eyes with 6-month postop specular measurements of central endothelial cell density (ECD) were analyzed. Percentage endothelial cell loss (ECL) was determined by subtracting 6 months ECD from donor preop ECD and dividing by preop ECD. ECL was compared between eyes that were re-bubbled and eyes that did not receive a re-bubble with statistical analysis by students t-test.

Results
69 DMEK cases had cell counts available at 6 months. There were 63 cases without re-bubble and 6 cases that had a re-bubble of air for partial graft separation. No case required two re-bubbles. Re-bubble cases had a mean ECD at 6 months of 1709 +/- 329 representing a cell loss of 33+/- 14%. Cases that did not require a re-bubble had a mean ECD at 6 months of 2012 +/- 483 representing a cell loss of 26 +/- 16%. There was no statistical difference between the percentage cell loss of DMEK cases re-bubbled and those that were not. (p=0.32)

Conclusion
Unlike DSAEK where a re-bubble is usually done for a free floating graft and results in higher cell loss at 6 months postop, a re-bubbling event in DMEK surgery is done for partial separations and does not appear to result in a greater loss of endothelial cells.