The effect of timolol, betaxolol and levobunolol on the surface of rabbit cornea.

Pigmented rabbits were treated with timolol maleate, betaxolol hydrochloride or levobunolol hydrochloride eye drops twice a day for six months. Animals of the same age group and breed were used as controls. There were no differences observed in corneal epithelium with light and transmission electron microscopy. With scanning electron microscopy, in the timolol and betaxolol treated animals the picture of the corneal surface was similar to that of normal rabbit corneas after exposure to air. In scanning electron micrographs of the levobunolol treated animals, the corneal surface resembled the corneas of normal rabbits treated with artificial tears.