In 1914, Friedberg 1 observed a virulent inflammation in the host tissue surrounding an implant 14 days postoperatively and inferred from this observation that the serological relationship played a role in graft healing. The inflammation, which was rapidly reduced, was tentatively interpreted as an anaphylactic reaction. Following this report, and especially recently, many authors, such as Muller and Maumenee, 2-4 Choyce 5 Babel and Bourquin, 6 Maumenee, 7 Morawiecki, 8 Basu and Ormsby, 9,10 Kornblueth, 11 Lieb and Lerman, 12 Kamata, 13 and Arai, 14,15 have recognized an antigen-antibody reaction after homo- and heterocorneal grafting. Postoperative graft opacity—the most unhappy complication of keratoplasty for the surgeon as well as the patient—may have a variety of causes. In 1948, Paufique, Sourdille, and Offretin 16 applied the term maladie du greffon to the opacity that arose inexplicably without manifest operative complications. Local allergy was regarded as one of the most important causal factors,