Long-Term Endothelial Outcomes and Dislocation Risks in Small Versus Large Grafts for Descemet’s Stripping Endothelial Keratoplasty

Background:This study compared the clinical outcomes of small-graft (7.0 mm <diameter 8.0 mm) versus large-graft (8.0 mm <diameter 9.0 mm) diameters in patients with bullous keratopathy (BK) undergoing Descemet's stripping endothelial keratoplasty (DSEK). Material/Methods:In this single-center, retrospective comparative study, 62 patients were divided into small-graft (n=28) and largegraft (n=34) groups based on the graft diameter.Best-corrected visual acuity (BCVA), endothelial cell density (ECD), endothelial cell loss (ECL) rate, graft transparency, and complications were evaluated at scheduled follow-ups at 1, 3, 6, and 12 months postoperatively. Results:At 12 months, the ECL rate was significantly lower in the large-graft group (20.078.17%)than in the smallgraft group (24.347.20%),with a mean difference of -4.27% (95% confidence interval [CI]: -8.23% to -0.07%, P=0.035).BCVA improvement and graft transparency were comparable between groups, with no significant difference in the 12-month graft survival rate (small-graft group: 96.43% vs large-graft group: 94.12%, P=0.788).However, the large-graft group (32.35%) had a significantly higher incidence of graft dislocation compared to the small-graft group (10.71%,P=0.043).The incidence rates of secondary glaucoma and graft rejection were comparable between groups. Conclusions:For BK patients undergoing DSEK, the use of larger grafts was associated with better long-term ECD preservation but also a higher observed incidence of graft dislocation.The selection of graft size should therefore be individualized, balancing the potential for enhanced endothelial survival against the elevated risk of postoperative dislocation.