Donor Age and Factors Related to Endothelial Cell Loss 10 Years after Penetrating Keratoplasty

Abstract

Objective To examine the effect of donor age and other perioperative factors on long term endothelial cell loss after penetrating keratoplasty (PKP) Design Multi-center, prospective, double-masked clinical trial Participants 176 participants from the Cornea Donor Study cohort who had not experienced graft failure 10 or more years after PKP for a moderate risk condition (principally Fuchs’ dystrophy or pseudophakic/aphakic corneal edema) Methods Corneas from donors 12 to 75 years old were assigned to participants using a randomized approach, without respect to recipient factors. Surgery and post-operative care were performed according to the surgeons’ usual routines. Images of the central endothelium were obtained preoperatively and at intervals for ten years postoperatively. Images were analyzed by a central image analysis reading center to determine endothelial cell density (ECD). Main Outcome Measure Endothelial cell density at 10 years Results Among study participants with a clear graft at 10 years, the 125 who received a cornea from a donor 12 to 65 years old experienced a median cell loss of 76%, resulting in a 10-year median ECD of 628 cells/mm2 (interquartile range, 522-850), whereas the 51 who received a cornea from a donor 66 to 75 years old experienced a cell loss of 79%, resulting in a median 10-year ECD of 550 cells/mm2 (interquartile range, 483-694) (P adjusted for baseline ECD=0.03). In addition to younger donor age, higher ECD values were significantly associated with higher baseline ECD (P<0.001) and larger donor tissue size (P<0.001). Forty-two (24%) of the 176 participants had an ECD below 500 cells/mm2 at 10 years and only 24 (14%) had an ECD above 1,000 cells/mm2. Conclusions Substantial cell loss occurs in eyes with a clear graft 10 years after PKP, with the rate of cell loss being slightly higher with older donor age. Higher pre-operative ECD and larger donor tissue size are associated with higher ECD at 10 years. Trial Registration NCT00006411

Long-Term Corneal Endothelial Cell Counts After Penetrating Keratoplasty in Infants

“…1 Expressed as endothelial cell density (ECD), one can predict the survival time of a given corneal graft, especially when planning an intraocular surgery. Studies focusing on specular microscopy results after penetrating keratoplasty (PKP) in adults [2][3][4] with Fuchs endothelial dystrophy and pseudophakic/aphakic corneal edema have shown a gradual endothelial cell loss (ECL) over time. The reported median ECL in the first 5 2 and 10 3,4 years after a successful PKP were 70% [interquartile range (IQR), 50%-77%] and 76% (IQR, 70%-82%), respectively.…”

Corona sign: manifestation of peripheral corneal epithelial edema as a possible marker of the progression of corneal endothelial dysfunction

“…Corona sign during chronic progression of graft endothelial dysfunction after PKP After PKP, the number of corneal endothelial cells in the corneal graft decreased over the long term [21]. The exacerbated corneal edema after PKP was seen during slitlamp examination; peripheral corneal edema as a corona sign in graft and/or host cornea was seen in 18 (grades 1 and 2) of 31 PKP cases (58.1 %) and increased in size in association with progression of corneal endothelial dysfunction in the PKP graft.…”

Donor Graft Quality Used for Penetrating Keratoplasty and Deep Anterior Lamellar Keratoplasty

“…Postoperative higher ECD values were significantly associated with higher baseline ECD and younger donor age in one study [34]. When the follow-up period was extended to 10 years, the study group observed that the donor age influenced ECD, although this finding was primarily influenced by a small group of the youngest donors (12 to < 34 years of age) that had the least cell loss and the best graft survival [34]. Lass et al [10] observed that younger age and female gender of the donor had a significant correlation with higher ECD over time.…”

“…Parekh et al [19] reported postmortem interval ≥ 10 hours tends to have a higher percentage of endothelial cell loss than < 10 hours of interval at both 1 year and 3 years postoperatively. Postoperative higher ECD values were significantly associated with higher baseline ECD and younger donor age in one study [34]. When the follow-up period was extended to 10 years, the study group observed that the donor age influenced ECD, although this finding was primarily influenced by a small group of the youngest donors (12 to < 34 years of age) that had the least cell loss and the best graft survival [34].…”

“…One study found a statistically significant negative influence of postmortem time and donor age on chronic loss of endothelial cell density after PK for keratoconus [35]. Because endothelial cell graft attrition takes place at an accelerated rate [36], a higher initial endothelial cell density of the donor tissue can improve long-term graft survival [34]. Older donor age and longer storage time are more likely to be associated with lower ECD but, as long as the ECD is greater than a given minimum at the time of corneal transplantation, these parameters will have insignificant influence on long-term graft survival.…”