Endothelial wound-healing in penetrating corneal graft for experimental bullous keratopathy in rabbit

Persistent bullous keratopathy was produced in one eye of a rabbit by anterior chamber irrigation with benzalkonium chloride solution (BAK). Corneal grafts were made from both eyes of another rabbit and they were transplanted to the eye with bullous keratopathy and the normal fellow eye, which served as the control. Subsequently, at intervals flat preparations of the endothelium of both eyes stained with silver nitrate were made. On panoramic photographs of the endothelium along one meridian of the cornea, the endothelial cell sizes were determined on both sides of the host-graft junction and at every 1 mm from the junction. In the control eyes the cell sizes increased, in the early postoperative period, near the host-graft junction both in the graft and in the host, and this increase gradually diminished by the end of the 6-month observation period. However, even after 6 months the mean cell size in both graft and host was slightly larger than the normal cell size. In the eye with bullous keratopathy, the cell size in the graft center increased rapidly and progressively. After 3 months the endothelial cells were seen in the host cornea and the cell sizes were considerably larger than those in the control cornea. After 6 months the cells were seen even in the periphery of the host cornea. In three sets of experiments, bullous keratopathy was produced in one eye of a male rabbit and the graft from a female rabbit was transplanted. Four months later, the detection frequency of the sex chromatin stained with acetic orcein was similar between the cells in the graft and in the host bullous cornea, indicating that the cells in the host had migrated from the graft.