生物玻璃陶瓷的生物相容性及其与角膜生物愈合特性的研究

目的：研究生物玻璃陶瓷（Bioglass Ceramic,BGC)在角膜中的生物相容性及其与角膜的生物愈合特性,寻找人工角膜支架材料。方法：将孔径20－70μm,孔隙率37－62％,厚度0.5mm,前后曲率半径7.8mm,直径6mm的BGC分别植入11只新西兰白兔角膜板层中。裂隙灯观察并照相,不同时间取材进行光镜检查。结果：最长观察8个月,5只实验2兔的植入物脱出,其中3只碎裂。术后第2,3周角膜新生血管增生明显。术后2个月,出现角膜浅层轻度混浊。光镜检查见植床内少量大小不一的灰色BGC团块,其间混杂红杂物质,周围角膜见大量增生成纤维细胞成同心圆样排列。结论：BGC植入角膜后有较高的脱出率,孔隙率5为1％,62T的BGC强度不够,植入后碎裂。BGC植入影响了角膜代谢,导致角膜前板层混浊。目前的切片技术与设备,较难获得良好的切片效果,难以评价BGC在角膜板层中的生物愈合特性。BGC目前的参数不适宜用于人工角膜的支架材料。

Tissue Interaction with Bioglass Ceramic Implanted in the Rabbit Cornea

Purpose: To evaluate the biocompatibility and 'healing' of Bioglass Ceramic(BGC) in the cornea.Methods: BGC dicks (8 mm in diameter, 0. 5 mm thick, 20 ~ 70 um pore diameter, 37 ~ 62% porosity, 7. 8 mm radius of curvature) were implanted in 11 New Zealand albino rabbits after a free-hand intralamellar dissection. The eyes were examined by slit-lamp biomicroscope up to seven months postoperatively. The corneas were removed at seven month (one eye at eight month), then were examined by light microscope. Results: Five of 11 dicks of BGC were extruded. All implant of BGC with 51 -62% porosity were broken and then extruded. A large part of implants led to markedly edematous with severe degrees of corneal neovascularization within one month postoperatively. The corneal lamella before implants became not clear in all eyes after two months. Lipid deposits occurred in four eyes. It is difficulty to observe the healing process of BGC in the cornea because the BGC is too hard to be cut in spite of being soft by 4% hydrochloric acid for four to ten days before cutting.Conclusion: Our findings suggest that BGC with above parameters is not suitable as peripheral keratoprosthetic materials because of its rough, hard, thick and breakable. Eye Science 2001; 17: 198~201.