Abstract
Purpose :
To identify donor and recipient factors, including donor tissue observations made by eye banks, predictive of tissue-related operative complications in the Cornea Preservation Time Study.
Methods :
1,330 study eyes undergoing DSAEK for Fuchs endothelial corneal dystrophy (94% of eyes) or pseudophakic or aphakic corneal edema (6% of eyes) were randomized to receive donor corneal tissue with a preservation time (PT) of 0-7 days (N=675) or 8-14 days (N=655). Donor factors included demographics, pre- and post-lamellar dissection thickness, epithelium intact or removed (on vs. off), prior to lamellar dissection, and endothelial cell density and tissue processing time variables, while recipient factors included demographics, lens status, IOP, and prior glaucoma medications or surgery. Eye bank observations included folds, edema, and endothelial cell abnormalities in the donor tissue. Operative complications considered possibly tissue-related included hyphema, inverted donor tissue, difficult unfolding and positioning, difficult air fill and retention, and reinsertion of donor after extrusion. Multivariable logistic regression with backwards selection was used to identify statistically significant (p<0.01) associations between factors and operative complications. Important variables of interest including the status of the donor epithelium (on vs. off during the measurement of thickness prior to dissection) and PT were forced in the final model.
Results :
Tissue-related operative complications occurred in 61 (4.6%) of 1330 surgeries. Only pre-lamellar dissection donor corneal thickness was predictive of operative complications and the strength of the association depended on whether the epithelium was on or off (p-value for interaction = 0.02). For every 50µ thicker a donor cornea was prior to dissection, the odds of an operative complication increased by 11% (OR [95% CI]: 1.11 [0.84 to 1.47]) with the epithelium off and 81% (1.81 [1.35 to 2.44]) with the epithelium on. PT was associated with increased pre-dissection thickness (mean thickness for PT 0-7 days is 538µ vs 568µ for PT 8-14 days; p<0.001).
Conclusions :
Thicker donor tissue (pre- lamellar dissection) is associated with an increased incidence of intra-operative complications, especially with epithelium on, and may be a factor to consider in tissue selection for lamellar dissection processing.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.