TRANSPLANTATION OF CORNEAL ENDOTHELIAL-CELLS USING A CELL CARRIER DEVICE

Penetrating keratoplasty is currently the only treatment for corneal e ndothelial dysfunction. Although corneal transplantation has a high su ccess rate, a few problems still remain, such as the limited availabil ity of donor grafts, the change in refraction after penetrating kerato plasty, and the higher chance of immune rejection. In this study, a co ated hydrogel lens (Chiron Ophthalmics Inc., Irvine CA, U.S.A.) has be en used as a carrier to transplant cultured homologous kitten and rabb it corneal endothelial cells into adult cats and rabbits. The transpla ntation procedure was the same in both species. Corneal endothelial ce lls from homologous rabbits or cats were seeded on coated hydrogel len ses and cultured until they reached a complete monolayer with an avera ge cell density of 2,500 cells/mm2. Five weeks before transplantation surgery, corneal endothelial cells were scraped to induce corneal edem a. The cell carrier device was then transplanted as follows: a trephin e cut (7.7 mm) was made into the stroma, producing an outer corneal pl ug. The inner cornea was then cut by using a 5.5-mm trephine, and this inner plug was discarded. The implant was inserted and the outer corn eal plug was sutured back into place. Corneas cleared completely withi n 3 days in both rabbits and cats, and stayed clear for an average of 40 days in rabbits and 50 days in cats. The histopathological evaluati on of the rejected grafts showed vascularized retrocorneal membrane fo rmation in cats, whereas in rabbits severe cellular infiltration of th e stroma with neovascularization occurred without retrocorneal membran e formation.