Abstract
Purpose :
When Descemet membrane endothelial keratoplasty (DMEK) grafts are processed for surgery, the graft naturally assumes a scrolled conformation. Younger aged donor grafts generally have a much tighter scroll than older grafts. More tightly scrolled grafts may require more manipulation/trauma than looser scrolled grafts for successful surgery. In this study we aim to determine if there is an association between DMEK scroll tightness, postoperative complications, and 6 month endothelial cell loss (ECL).
Methods :
A retrospective chart review was conducted for patients receiving a DMEK graft for endothelial dysfunction from 9/2013-10/2019. Prior to tissue injection, we subjectively scored each graft on a scale of 1-4 based on the tightness of the scroll (1 = very loose scroll and 4 = very tightly scrolled). DMEK grafts were separated into 4 groups based on their scroll tightness score (1-4) for analysis. Grafts were compared for intraoperative un-scroll times, post-op re-bubble rate, 6 month postoperative ECL, and primary graft failure (PGF). Statistical significance was determined using a chi square test or Kruskal-Wallis test.
Results :
A total of 1,148 DMEK surgeries with a scroll tightness score were evaluated. Mean un-scroll time (minutes) for grafts scored 1,2,3 and 4 were 2.5, 3.5, 4.6, and 4.9, respectively, P<0.001. Re-bubble rate for 1 scrolls = 33/208 eyes (15.9%), 2 scrolls= 84/544 eyes (15.4%), 3 scrolls= 28/271 eyes (10.3%), and 4 scrolls = 13/125 eyes (10.4%), P=0.114. Mean 6 months postoperative ECL for grafts scored 1,2,3, and 4 were 31.2% (n=124), 31.2% (n=336), 30.3% (n=170), and 33.4% (n=78), respectively, P=0.660. 14 cases of PGF (1% rate overall) were recorded (1’s=2 PGFs, 2’s=9 PGF’s, 3’s=1 PGF, 4’s=2 PGF’s), P=0.288.
Conclusions :
The tighter the graft was scrolled, the longer it took to manipulate the graft to un-scroll. Amazingly, more loosely scrolled grafts (1 and 2) had approximately 50% higher re-bubble rate compared to tighter grafts (3 and 4). Contact with injector walls may be a factor. Scroll tightness did not influence 6 months ECL or the primary graft failure rate. Overall, our short-term clinical outcomes show that successful DMEK surgery can be achieved with any scroll tightness within the specified un-scrolling times for each group.
This is a 2020 ARVO Annual Meeting abstract.