[The influence of cryoprotective solutions on the ultrastructure of rabbit corneal endothelium (author's transl)].

A series of rabbit corneae was preserved at -196 degrees C in liquid nitrogen using five different cryoprotective solutions: (1) 5% dextran T 40, (2) 10% polyvinylpyrrolidone, (3) 5% dextran T 40 + 10% polyvinylpyrrolidone + dimethyl sulfoxide, (4) 25% rabbit albumin + 10% polyvinylpyrrolidone, (5) 25% rabbit albumin + dimethyl sulfoxide. After thawing the corneae, the influence of the different cryoprotective solutions on the ultrastructure of corneal endothelium was evaluated and compared with fresh corneae. The results were as follows: (1) Using 5% dextran T 40 or 10% polyvinylpyrrolidone or 25% rabbit albumin as cryoprotective solutions marked intracellular damage. (2) Adding dimethyl sulfoxide to the solutions cryopreservation appeared to be more successful at the cellular basis, despite the freezing and thawing procedure mediated moderate intracellular changes. Cryopreservation including dimethyl sulfoxide renders better conditions for successful corneal grafting in the light of ultrastructural aspects.