Effect of Donor Graft Quality on Clinical Outcomes After Deep Anterior Lamellar Keratoplasty

PURPOSE:The aim of this study was to determine the effect of donor features, including age, death-to-preservation time, preservation-to-surgery time, graft rating, and endothelial cell features, on visual and refractive outcomes and complications occurring after deep anterior lamellar keratoplasty (DALK) in patients with keratoconus. METHODS:In this retrospective study, 290 consecutive keratoconic eyes underwent DALK using donor corneas of different qualities, ranging from fair to excellent. Donor corneas were stored in intermediate-term storage medium. Donor data included age and sex, death-to-preservation time, preservation-to-surgery time, epithelial and stromal status, endothelial cell density and morphology, and graft rating. Postoperative outcomes included visual acuity, refractive error, epithelial problems, suture-related complications, graft rejection, and graft transparency. A multivariate regression analysis was used to assess the correlation between donor characteristics and postoperative outcomes. RESULTS:Mean donor and recipient ages were 33.4 ± 13.1 and 27.7 ± 8.0 years, respectively. The mean follow-up period was 38.2 ± 20.2 months. The presence of epithelial defects on postoperative day 1 had a significant correlation with donor epithelial sloughing (R = 0.26, P < 0.001), preservation-to-surgery time (R = 0.21, P = 0.001), and graft rating (R = −0.17, P = 0.004). Graft stromal edema on postoperative day 1 was significantly correlated with donor epithelial sloughing (R = 0.31, P < 0.001), preservation-to-surgery time (R = 0.24, P < 0.001), and graft rating (R = −0.28, P < 0.001). Suture-related complications, graft rejection episodes, graft clarity, visual acuity, and refractive outcomes at the final follow-up examination were found to have no correlations with any donor factors. CONCLUSIONS:The use of low-quality donors for DALK increased the rate of epithelial defects and stromal edema immediately postoperatively. However, the donor features had no influence on visual and refractive outcomes and complications.