Influential factors on the survival of endothelial cells after penetrating keratoplasty

PURPOSE: To evaluate the factors that influence the survival of corneal endothelial cells after penetrating keratoplasty. METHODS: We retrospectively reviewed the medical records of 83 eyes of 83 patients who had undergone penetrating keratoplasty and whose corneal endothelial cell density was more than 2,000 cells/mm2 at postoperative 1 month. The patients were divided into 3 groups: keratoconus (Group 1), bullous keratopathy (Group 2), and herpetic keratitis with uveitis (Group 3), based on the underlying disease and the recipient's corneal endothelial state. We analyzed the difference of endothelial cell loss among the 3 groups and some risk factors such as preoperative glaucoma, postoperative increased intraocular pressure, graft rejection, peripheral corneal disease, and the donor trephine size. RESULTS: The corneal endothelium cell loss was significantly higher in Groups 2 and 3 than in Group 1 after 2 years. There were statistically significant differences of the rate of corneal endothelium cell loss for the eyes with preoperative glaucoma, postoperative glaucoma medication with more than 2 agents, graft rejection, and peripheral corneal disease, but the donor trephine size was not a significant factor for corneal endothelium cell loss. CONCLUSIONS: For the eyes with bullous keratopathy and herpetic keratitis with uveitis, the survival rate of the endothelium was lower than that for the eyes with keratoconus. We should carefully manage patients who have risk factors such as graft rejection, peripheral corneal disease, and perioperative glaucoma to minimize the loss of corneal endothelium and to reduce graft failure after penetrating keratoplasty.