2ND GENERATION BIOINTEGRABLE KERATOPROSTH ESIS (BIOKPRO-II) - ANIMAL STUDY

Purpose Our goal was to evaluate a second generation biointegrable ker atoprosthetic device (BioKpro II). Methods The device consists of a po rous transparent PTFE (12 mm diameter) and a soft copolymer structure for the optical system (7 mm diameter). Intraocular pression was evalu ated with a Goldman tonometer on an artificial chamber. A lamellar dis section was carried out 3 mm radially for 360 degrees creating a pocke t to accomodate the skirt. The soft optic (42,5 D; 500 microns thick) was performed and conjunctiva was placed in front of the prosthesis, s utured and was opened 15 days post implantation. 14 rabbits were impla nted and were allowed to heal for three months. Results We are able to measure the intraocular pressure by Goldmann tonometer on an artifici al chamber. We did not observed epithelialisation on the hydrophilic o ptical surface (14/14). Aseptic necrosis in direct contact between cor nea and the soft optical system was observed when conjunctiva was not effective (4/14). As observed with the first generation devices, conju nctiva or buccal mucosa is needed to avoid local necrosis. In other ca ses no adverse reactions were observed after implantation. Discussion The geometry and biomechanical properties of the BioKpro II is closed to that of the human cornea. The junction between the optical and the flange was bound by polymeric interpenetration and prosthesis dislocat ion was not seen under pressure over 1000 mmHg. Conclusion Second gene ration biointegrable keratoprostheses (BioKpro II) can be implanted su ccessfully. Further tests will determine if surface modifications desi gned to promote epithelial cell attachment on the optical system could prevent ulceration at the junction between the fluorocarbon and the c ore.