[Keratoprosthesis: study of an expanded polytetrafluoroethylene support].

Expanded Polytetrafluoroethylene (E. PTFE) is an inert vitreous teflon alloplast with a high biocompatibility. It is able to be ingrowth by fibrovascular tissue. Very good results are reported in vascular, abdominal and reconstructive surgery and this suggests a possible use in keratoprosthesis. In this purpose, its tolerance and its embedding in the corneal tissues have been studied. Eight perforating keratoplasties are performed in the rabbit with a diameter of 5 mm. A disk of E. PTFE was sutured on the cornea and examined clinically, histologically and by scanning electron microscopy from 1 to 50 days after the operation. Corneal implants are well tolerated but microscopic examination does not show evidence of fibrovascular ingrowth. A full thickness corneal implant seems uneffective in the absence of a conjunctival flap.