Clinical, Physical Stability and Histological Biocompatibility of Experimental Seoul Type Keratoprosthesis

ABSTRACT

In cases that penetrating keratoplasty do not help to improve vision, keratoprosthesis implantation is necessary. This study was performed to assess clinical and mechanical stability of Seoul type-keratoprosthesis[SKPro], bio-compatibility and effect of amniotic membrane transplantation on clinical and mechanical stability of SKPro. SKPro consists of an optic portion made of PMMA, a skirt of Gore-tex or polyurethane and a haptic of prolene. The skirt of SKPro was covered with recipient conjunctiva completely at postoperative 1 month and melting of covered conjunctiva and exposure of skirt developed at postoperative 2 months and progressed slowly to postoperative 6 months. But retroprosthetic membrane formation, extrusion of SKPro, posterior segment complication such as retinal detachment did not develop and transplanted SKPro showed relatively good clinical stability during 6 months. Pressure loading test showed relatively good mechanical stability under high pressure at postoperative 2 months. Histologic study showed moderate inflammatory reaction and abnormal pattern of collagen and extracellular matrix in lamellar pocket and anterior flap. There was no deposit of collagen in Gore-tex skirt. But histology of posterior flap of lamellar pocket was nearly normal. Group that was transplanted with amniotic membrane twice showed more better stability than once and without amniotic membrane transplantation on clinical and mechanical stability.