Development of bioabsorbable artificial dura mater

研究可吸血人工硬脑膜物质。研制了l -乙酸、乙醇酸和己内酯共聚物制备的实验膜。首先通过体外泄漏试验验证了材料的有效性。用猪硬脑膜缝合发达的膜，在确定的压力下测量生理盐水漏出量，达到临床最高颅脑压6OmmHg。虽然防止了针孔渗漏，但在高压下仍观察到针缝渗漏。这种类型的渗漏与缝合方法有关，单节缝线张力大的情况最糟糕，而连续简单缝合，张力小，间距合适，效果最好，几乎可以完全防止渗漏。接下来，我们以大鼠作为实验动物，通过体内试验来检测材料的生物相容性。在大鼠硬脑膜两侧各制造5x10mm的人工缺损。将发育好的膜套在缺损上并缝合。分别于植入4、8、12周后取标本。检查渗漏、再生及周围组织。术后4周，发达的膜被柔软的纤维组织包围。进行了泄漏试验，在60mmHg压力下无泄漏。组织学观察证实12周后无炎症反应，显示硬脑膜再生合理。

Bloabsorbable artificial dura matter was investigated. Experimental membranes made from copolymers of L-Iactlc acid, glycolic acid and caprolactone were developed. The effectiveness of the materials was firstly verified with a leaking test In vitro. The developed membranes were sutured with swine dura matter and amount of leaked saline under determined pressure upto 6OmmHg, the maximum brain pressure in clinical situation, were measured. Although the leak from a needle hole was prevented, the leak through the stitch under high pressure was observed. This type of leakages was found to be dependent on the method of suturing, worst in the cases of single knot with high suture tension, whereas the continuous simple suturing with less tension and suitable pitch gave the best results and almost complete prevention of leakage was possible. Next we examined the biocompatibilities of the materials with the In vivo test In which we used rats as experimental animals. Artificial defects of 5x10mm were made in each side of rats dura matter. The developed membranes were set on the defects and sutured. The specimens were retrieved after 4, 8, and 12 weeks of implantation. Leakage, regeneration, and surrounding tissues were examined. 4 weeks postoperation, the developed membranes were surrounded with the soft fibrous tissues. The leakage tests were carried out and no leakage was proved under 60mmHg of pressures. Histological observation verified no inflammation response after 12 weeks, and revealed the reasonable regeneration of dura matter.