Histopathological observation of new soft one-piece keratoprosthesis skirt implanted into alkali burned rabbit corneas / 中国组织工程研究

ABSTRACT

BACKGROUND:Polyhydroxyethyl methacrylate has excel ent optical properties and good hydrophilicity which has been widely applied in biological materials, such as contact lenses, intraocular lenses. In previous experiments, artificial corneas made of polyhydroxyethyl methacrylate subcutaneously implanted or implanted into normal rabbit cornea have showed good biocompatibility and tear resistance. OBJECTIVE:To evaluate the histopathological results of the porous skirt of new type one-piece keratoprosthesis made of polyhydroxyethyl methacrylate implanted to alkali burned rabbit corneas. METHODS:New blood vessels and wal eyes formed in New Zealand rabbits at 3 months after alkali burned rabbit corneas. The porous discs of polyhydroxyethyl methacrylate were inserted into the lamel ar pocket of alkali-burned corneas and the corneas were observed clinical y, histological y and ultrastructural y at 2, 8, 16 and 28 weeks after implantation,. RESULTS AND CONCLUSION: Histopathology suggested that mild inflammatory reaction and no calcification were seen in al specimens, fibroblasts and deposition of col agens were found in the pores of the dics at 2 weeks after implantation;stable connection with cornea was formed by the end of 16 weeks;the pores were almost completely fil ed with new tissue, the number of cel s decreased, and mature fibers were mainly found at 28 weeks. Scanning electron microscope showed new tissue grew into the pores which were closely connected with the corneas. Transmission electron microscope exhibited cytoplasm migrating into the material was rich in rough endoplasmic reticula, showing strong synthetic function, col agen, proteoglycans, and other extracel ular matrix deposition. These findings indicate that the porous skirt of polyhydroxyethyl methacrylate implanted into the alkali burned rabbit corneas al owed corneal cel s migration, proliferation, secretion of the deposition of extracel ular matrix and the formation of new tissue to complete the stable connection with cornea, showing a better biocompatibility.