Abstract
Purpose:
Graft detachment remains the most frequent postoperative complication of Descemet membrane endothelial keratoplasty (DMEK) surgery. This study aims to determine whether the extent of Descemet membrane (DM) scroll formation has an impact on the rate of postoperative graft detachment.
Methods:
We performed a retrospective analysis of the clinical records of the 100 consecutive cases of DMEK surgery performed at the University of Erlangen-Nuremberg between September 2014 and November 2014. The extent of scroll formation of donor DMs had been graded by comparing it to the lumen of the injector cartridge (Medicel AG, Wolfhalden, Switzerland): Weak scrolling was defined as a scroll diameter > 4.6 mm (outer diameter of the graft injector cartridge), whereas tight scrolling was defined as a scroll diameter < 3.6 mm (inner diameter of the graft injector cartridge). Clinically relevant postoperative graft detachment that needed re-injection of an anterior chamber air bubble was defined as detachment with a height of more than 1 thickness of the corneal stroma (> 500 µm measured by SL-OCT) and an extent of more than 1 quadrant.
Results:
In 100 data sets analyzed, 25 DMs were classified as weak scrolling, and 42 DMs were classified as tight scrolling. The remaining 33 showed medium scrolling (between 4.6 mm - 3,6 mm) Mean donor age in these two groups was 75 years and 67 years, respectively (p<0.001). Other parameters, including graft endothelial cell count or recipient age did not differ significantly between both groups. Graft detachment to an extent that prompted rebubbling occurred in only 1 patient (4%) in the weak scrolling group vs. 2 patients (4.8%) in the very strong scrolling group (p=0.89). Overall the rate of graft detachment requiring rebubbeling was very low.
Conclusions:
The tendency of younger grafts towards tighter scrolling was confirmed. Despite this difference in DM behavior this small series did not show any statistically effect of scrolling on postoperative rates of graft detection. Other potential influencing factors may include structural changes of DM or metabolic disease in donor or recipient, among others. Further analysis is warranted to minimize the risk for graft detachment.