Five-Year Graft Survival of Descemet Membrane Endothelial Keratoplasty (EK) versus Descemet Stripping EK and the Effect of Donor Sex Matching

Abstract

To determine whether the reduced risk of immunologic rejection with Descemet membrane endothelial keratoplasty (DMEK) results in a 5-year survival advantage relative to Descemet stripping endothelial keratoplasty (DSEK) and to determine whether matching the donor and recipient sex affects the rejection episode and graft survival rates. Retrospective cohort study. Patients with Fuchs' endothelial corneal dystrophy treated with DSEK or DMEK. This study reviewed 2017 consecutive cases (1312 DSEK and 705 DMEK) performed by 13 surgeons between 2003 and 2012 and included the surgeons' first cases. Survival rates were calculated by Kaplan-Meier analysis. Immunologic rejection episodes, graft failure or replacement for any reason, and endothelial cell loss. The 5-year rejection episode rate was lower with DMEK (2.6% vs. 7.9% with DSEK, relative risk, 0.29; 95% confidence interval, 0.16-0.53) despite early reduction of topical corticosteroids in 25% of the DMEK cases. African Americans (n= 46) had a higher risk of rejection episodes than other races (relative risk, 4.4; 95% confidence interval, 2.0-9.6). The cumulative 5-year survival rate was 93% with DSEK and DMEK (P= 0.86). Forty-four DMEK and 69 DSEK grafts failed or were replaced within 5 years, but only 1 DMEK and 4 DSEK failures followed a rejection episode. Rejection episodes increased endothelial cell loss (P= 0.004) but were not a significant risk factor for graft failure within 5 years (P= 0.90). The mean 5-year endothelial cell loss was similar between DMEK (48%±19%) and DSEK (47%±19%) (P= 0.22). Graft rejection episode and survival rates were not significantly influenced by whether the sex of the donor matched that of the recipient (rejection episodes: P= 0.07 for female recipients and P= 0.33 for male recipients; graft survival: P=0.67 for female recipients and P= 0.17 for male recipients). Five-year graft survival was similar between DMEK and DSEK. Although DMEK had a significantly lower risk of immunologic rejection, rejection episodes rarely resulted in graft failure within 5 years with either procedure. Sex matching the donor and recipient provided no survival advantage with DSEK or DMEK.