LAMELLAR, or nonpenetrating, corneal transplantation is not a new surgical procedure. This type of keratoplasty was introduced by von Hippel1 in 1888, after a decade of discouraging experience with penetrating transplants. Using dog or rabbit cornea as donor material. he placed a full thickness graft in a window in the host cornea trephined to the depth of Descemet's membrane (posterior elastic membrane). Discussing the advantages of this operation, von Hippel stated that the lamellar operation was easier to perform than penetrating keratoplasty. that there was no danger of trauma to.the inner structures of the eye or of loss of vitreous, that the graft was more easily held in position and that the graft healed more rapidly because of better nutrition. After complete healing had occurred, von Hippel observed nebulous scarring over the base of the graft, which never entirely disappeared, although usually the cornea remained clearer than the original