Graft survival studies are important to evaluate the longevity of transplanted donor corneal tissue. Since 1998, corneal transplantation has undergone an evolution from conventional techniques such as penetrating keratoplasty to minimally invasive techniques such as Descemet stripping (automated) endothelial keratoplasty, and Descemet membrane endothelial keratoplasty for the treatment of corneal endothelial diseases.1