Effect of Donor Graft Quality on Clinical Outcomes After Penetrating Keratoplasty for Keratoconus

PURPOSE To evaluate the effect of donor and eye bank characteristics on graft rating and clinical outcomes after penetrating keratoplasty (PK) for keratoconus. METHODS This retrospective interventional case series included 252 keratoconic eyes which underwent PK. Donor data included age and sex, cause of death, death-to-preservation time, preservation-to-surgery time, epithelial and stromal status, endothelial cell density (ECD) and morphology, and graft rating. Postoperative outcomes included visual acuity, refractive error, epithelial problems, suture-related complications, graft rejection, and graft transparency. Multivariate regression analysis assessed correlations between donor and eye bank characteristics and graft quality, and postoperative outcomes. RESULTS Mean recipient and donor age was 29.7 ± 10.0 and 26.2 ± 8.8 years, respectively and mean follow-up period was 66.7 ± 38.5 months. Death-to-preservation time was significantly associated with the presence of graft epithelial sloughing (P = 0.005) and stromal cloudiness (P < 0.001). Donor age significantly influenced ECD (P = 0.02), mean cell area (P = 0.04), and hexagonality (P = 0.01). The presence of epithelial defects on postoperative day 1 correlated significantly with death-to-preservation time (P = 0.004). Graft stromal edema on postoperative day 1 was significantly associated with graft epithelial sloughing (P < 0.001). Postoperative visual and refractive outcomes, complications, and graft survival were not correlated with any donor or eye bank factors. CONCLUSION Donor and eye bank variables affected the quality of donor corneas and early postoperative course. However, their long term effect on clinical outcomes, complications, and graft survival were insignificant.