国产化人工角膜植入兔眼的稳定性评估

The assessment of stability of the domestic keratoprosthesis implanted into rabbit＇s cornea

目的评价国产化人工角膜在兔眼角膜中的中长期稳定性。方法实验研究。采用长耳大白兔10只，均选右眼作为国产化Moroz改良型永久性人工角膜植入眼，左眼为对照眼。手术分两期完成，一期手术用第三眼睑（软骨组织与人耳软骨有类似效果）加固角膜前层，联合自体结膜遮盖植入人工角膜支架；3个月后进行二期手术，植入人工角膜镜柱。全部手术完成后观察6个月以上。术后抗生素滴眼预防感染，定期观察，照相记录。最终行眼组织病理学检查。并与左眼进行对照。结果除1只兔在二期术中因麻醉意外死亡外，9只兔均顺利完成手术和术后观察，术后各观察时间点人工角膜均在位，眼表血管化良好，未发生角膜组织融解、房水渗漏、高眼压、感染等严重并发症。组织病理学检查显示：加固的软骨组织均在位，人工角膜支架与周围组织紧密结合，有较活跃的纤维组织增生包绕，角膜炎症反应很轻。对侧眼无异常。结论国产化人工角膜具有良好的生物相容性和中长期在位稳定性，用耳软骨加固和自体结膜遮盖有助于提高人工角膜稳定性。

Objective To analyze the long-term stability of domestic keratoprosthesis （Kpro） after its application in rabbits＇ corneas. Methods In this experimental study, domestic permanent modified keratoprosthesis （Moroz Kpro） were implanted in the right eyes of 10 rabbits. The left eyes served as control. Surgery involved two steps： Successively implantation of titanium frame first and then the implantation of optical cylinder. In the first stage, the third eyelid （cartilage, equivalent to） was removed and used as reinforcement of corneal surface and then autologous conjunctival was covered at the surface （Stage 1）; secondly, an optical cylinder was implanted 3 months after the first stage （Stage 2）. Postoperative observation follow up for 6 months. Postoperative antibiotic eye drops were given to prevent infection. Finally the corneas were observed histopathological, compared with the left eyes. Results One rabbit died because of intraoperative anesthesia during the operation of stage 2. The other 9 rabbits survived till the end of 6-month follow up. These Kpros retained till the end without severe complications, such as corneal melting, aqueous humor leakage, high intraocular pressure or infection etc. Biopsy specimen showed： The cartilages were in place; the frame and the surrounding tissue combined closely; there was a more active proliferation of fibrous tissue around the Kpro, and the keratitis reactions were very slight. The left eyes were normal. Conclusion Domestic keratoprosthesis has a good biocompatibility and stability after the application in the cornea of rabbits. The apphcation of cartilage and autologous conjunctival play an important role in the success of keratoprosthesis retention.