摘要
OBJECTIVE: To investigate the biomechanical characters of human dura and its substitutes and to establish guidelines for selection of optimal repair materials for reconstruction of skull base defects. METHODS: A measurement of creep properties of human dura and its substitutes were conducted using biomechanical tests. The dynamic changes of biomechanical properties of canine dura obtained from skull base defects were observed as well. RESULTS: The creep properties of human dura presented a linear-relationship between initial strain and stress, and the creep strain increased slowly with time. The creep compliance formula for human dura and its substitutes was as follows: J (t) = J(0) + Kf (t). The initial compliance of canine dura in skull base defects was reduced by 35%, 46% and 50%, respectively 1, 3 and 6 months after surgery. CONCLUSION: The optimal material for the repair of skull base defects can be estimated using creep compliance analysis. The less the compliance, the better the property of anti-protrusion. Fresh human dura is the least compliant and then in increasing order are lyophilized human dura, fresh human pericranium, Terylene and silicon membranes. The pattern of biomechanical characteristics of the dura mater at skull base defects shows that the strain ability of the dura mater decreases distinctly for 1 - 3 months and then remains almost unchanged for 3 - 6 months after surgery.
目的 测试与分析人硬脑膜及其替代物的生物力学特性 ,为选择理想的颅底缺损重建材料提供依据。方法 通过生物力学试验测定人硬脑膜及其替代物的蠕变特性 ,通过动物实验测定狗颅骨缺损区硬脑膜生物力学特性的动态变化。结果 人体硬脑膜的蠕变特征为 :初始应变和所加的应力大体成线性关系 ;蠕变应变随时间缓慢增加。表示人体硬脑膜及其替代材料蠕变特性的柔度公式的一般形式为 :J(t) =J0 +Kf(t)。颅底缺损区硬脑膜初始应变的动态变化是 :术后 1个月减少约 35 % ,术后 3个月减少约为 4 6 % ,术后 6个月减少约为 5 0 %。结论 可用蠕变柔度测试判断颅底骨缺损硬脑膜修补材料的优劣 ,柔度愈小 ,抗膨出性能愈好。新鲜人硬脑膜的柔度最小 ,冻干人硬脑膜、新鲜人颅骨膜、硅橡胶膜、涤纶片的柔度依次增大。颅底缺损区硬脑膜蠕变减少的程度随时间延长而逐渐增加 ,术后 1- 3月减少明显 ,3- 6月变化趋缓。
基金
ThisstudywassupportedbyagrantfromtheNationalNaturalScienceFoundationofChina (No 3 9670 199)