Abstract
Purpose :
Descemet Membrane Endothelial Keratoplasty (DMEK) has a high processing failure rate compared to Descemet Stripping Automated Endothelial Keratoplasty (DSAEK). A limited number of studies have identified potential risk factors for damage but more studies are needed to determine their validity. We report an analysis of potential risk factors from a previously unstudied eye bank performing high volume DMEK processing.
Methods :
Retrospective study of all 385 DMEK tissues processed from 319 eligible donors at Saving Sight Eye Bank between July 2014 and June 2017. The primary outcome of interest was DMEK preparation-associated damage. Factors that were analyzed included donor past medical history, tissue characteristics, and eye bank technician characteristics. Analysis was completed with logistic regressions.
Results :
There were 32 cases of processing damage (8.3%). Univariate analysis showed no significant differences in damage with respect to donor age (p=0.305), gender (p=0.738), race (p=0.275), history of hyperlipidemia (p=0.401), obesity (p=0.316), phakia (p=0.074), death to preservation time (p=0.698), death to processing time (p=0.254), and preprocessing endothelial cell density (p=0.189). Univariate analysis showed that donor diabetes mellitus (DM) was associated with more frequent damage (OR 3.38, p=0.001). 5 technicians were studied. Each technician processed between 3 and 195 DMEK tissues. Rates of damage per technician were 0.0% (0 of 3), 2.1% (1 of 47), 7.2% (14 of 195), 8.5% (7 of 82), and 17.2% (10 of 58). The technician with the highest failure rate was statistically significantly different than the other technicians combined (p=0.01). Mixed effect analysis showed that there was a statistically significant trend of more failures during the first 25 DMEK cases per technician than the later cases (p=0.011). Technician experience with DSAEK prior to their first DMEK, ranged from 14 to 1,539 cases and was not statistically significantly associated with subsequent DMEK success (p=0.416). Elimination of tissues with the statistically significant risk factors reduced the failure rate from 8.3% to 4.1%.
Conclusions :
Eye bank DMEK processing has significant rates of damage. Risk factors for processing failure include donor DM status, individual technician ability, and technician learning curves.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.