Fifty-seven penetrating keratoplasties were performed using human donor corneal material stored in modified Tissue Culture Medium 199 (TC-199). Fifty-six grafts were clear on the first postoperative day and remained clear for at least three weeks. During the follow-up period (average, 3.7 months), only four additional graft failures occurred. The reduced incidence of early graft edema is attributed to prolonged viability of corneal endothelium maintained in modified TC-199 medium prior to keratoplasty.