Endothelial Cell Decay after Descemet's Stripping Automated Endothelial Keratoplasty and Top Hat Penetrating Keratoplasty

Abstract

To analyze endothelial cell density (ECD) decay after Descemet's stripping automated endothelial keratoplasty (DSAEK) and top hat keratoplasty (THPK) in patients with Fuchs' endothelial dystrophy (FED) and/or pseudophakic bullous keratopathy (PPBK). Patients underwent either THPK (n = 33) or DSAEK (n = 39) at the Erasmus Medical Center, Rotterdam. For each nonrandomized cohort, a biexponential regression model for ECD decay was fitted. Factors associated with higher ECD decay were evaluated. Median follow-up was 31.2 months (range, 11-91) in the THPK cohort, and 23.4 months (range, 6-61) in the DSAEK group. The early ECD decay was much higher after DSAEK (half time, 2.2 months) than after THPK (half time, 12.8 months). The late ECD decay after DSAEK was less steep (half time, 75.5 months) than after THPK (half time, 62 months). The 1-, 3- and 5-year endothelial cell losses derived from the models after DSAEK were 56%, 66%, and 73%, respectively, and after THPK were 24%, 50%, and 64%, respectively. For the DSAEK cohort, PPBK as an indication for surgery was associated with significantly higher late-phase decay rates. For the top-hat cohort, a significantly lower late-phase decay rate was found in PPBK. FED and same-session cataract surgery were confounding variables in the DSAEK cohort. Regarding DSAEK, postoperative re-bubbling was not found to have significant effects on early or late ECD decay rates. However, the small sample size and other limitations related to the method of evaluation may have influenced these findings. After DSAEK, early ECD decay was stronger than after THPK, as opposed to late decay. Late decay was faster for PPBK than for FED after DSAEK.