The Effect of Donor- and Recipient-Related Factors on Corneal Graft Survival in Penetrating Keratoplasty

Purpose: To investigate the impact of donor and recipient factors on graft survival in penetrating keratoplasty (PK).

Material and Methods: This retrospective study included 365 eyes that underwent PK using corneas from 231 donors between June 2010 and June 2015. Patients were divided into three groups (group 1: primary endothelial diseases; group 2: iatrogenic endothelial disorders; and group 3: other pathologies with a healthy endothelium) according to PK indications. The primary outcome measure was corneal graft survival at the last visit (clear or opaque). Graft clarity was assessed using Kaplan–Meier survival analysis.

Results: The most frequent PK indication was keratoconus (KC) (20.5%) followed by pseudophakic bullous keratopathy (PBK) (18.9%). Donor age had a negative impact on endothelial cell density (ECD) measured by an eye bank specular microscope (p < 0.001). Median best-corrected visual acuity in logarithm of the minimum angle of resolution units increased from 2.1 to 0.8 at 1 year after PK (p < 0.001). The clear graft rate was 96.7% at year 1, 88.8% at year 2, and 85.5% at year 3. Overall graft survival was 84.9% during a median of 39 months (range: 24–79 months) of follow-up. A higher graft survival rate (67.2%) was observed in KC compared to PBK during 6 years (p < 0.001). Recipients younger than 50 years of age showed a better graft survival rate than those older than 70 years of age (p = 0.037). Donor ECD, time between excision and death, and preservation time had no significant effect on graft survival. Frequent graft rejection episodes (GREs) and additional procedures during surgery had a negative impact on graft survival (p < 0.001 and p = 0.014, respectively). A worse graft survival was observed in group 2 compared to groups 1 and 3 (p = 0.042).

Conclusions: Young recipient age and KC were associated with a better graft survival. Graft endothelial density and preservation time had no impact on graft survival. PBK, low vision at baseline and year 1, frequent GREs, and additional interventions during surgery had a negative impact on graft survivals.