Opacification, vascularization, and chronic inflammation produced by hydrogel corneal lamellar implants

Fourteen hydrogel lamellar implants were placed in rabbit corneal stroma. Within six months of implantation, all the rabbit eyes showed some opacification of the cornea, and several of the rabbits had vascularization along the lamellar interface with signs of chronic inflammation. Opacification and vascularization eventually appeared in all 14 eyes, regardless of the water content or oxygen permeability of the lens material. One rabbit was killed, and a histopathologic examination showed evidence of chronic inflammation and scarring. Because the rabbit's sensitivity to an inflammatory nidus makes it a good laboratory test animal, these rabbits' inability to tolerate some of the currently available hydrogel corneal lamellar implants may indicate that such material is unsuitable as a permanent implant for cosmetic refractive surgery in humans.