目的利用寰枢关节并椎动脉增强CT扫描容积数据进行有限元建模,探讨建模的可行性及可能应用价值。方法选取良好的CT扫描数据,其中包括寰枢关节、部分枕骨、第3颈椎及椎动脉数据,使用阈值及手工结合技术将各个椎体、椎动脉区分开来并保存为STL格式文件,在NETGEN自写的软件中进行几何模型及有限元模型建立,调整相关参数获取满意的有限元模型。结果寰枢关节CT容积数据建模方法相对简单,获取的有限元模型结构清楚、逼真,模型图像显示解剖结构满意。与常规CT重建的三维图像进行比较,不仅能清楚地显示了寰枢关节、椎动脉等结构的形态,也能方便地选择性显示单一结构并进行三维解剖测量,实现与断面图像的相互补充,更具有寰枢关节旋转运动及受力分析等功能。结论利用CT容积数据进行寰枢关节有限元建模,其方法可行、图像真实,同时可信度高。该模型的建立为相关生物力学、解剖关系的研究提供了基础与条件。
Objective With the volume data of atlantoaxial joint and vertebral artery by contrast-enhanced CT scan,this study has established the finite element modeling and explored its feasibility and possible applications. Methods To select the CT voiume data,including the atlantoaxial joint vertebral artery,and to use the technique of threshold and manual foreach vertebral body, vertebral artery is distinguished and saved as the STL format. In the NETGEN of self-writing software, the atlantoaxial joint of geometric model and finite element model were established with adjusting the relevant parameters,and the satisfactory finite element model was obtained. Results The modeling method with CT volume data is relatively simple, getting the finite element model with the clear structure. Compared with the 3D images of conventional CT reconstructed, it can clearly not only observe the morphological structure of atlantoaxial joints and vertebral artery, but also selectively display or measure one of structures and make the atlantoaxial rotary motion or mechanical analysis. Conclusion Finite element modeling of atlantoaxial joint with CT volume data is practical and the model is of high reliability. It can provide the basis and condition for biomechanical and anatomic study.