Tizzard A, Bayford R H
Middlesex University, Trent Park Campus, London N14 4XS, UK.
Physiol Meas. 2007 Jul;28(7):S163-82. doi: 10.1088/0967-3334/28/7/S13. Epub 2007 Jun 26.
As the use of realistic geometry in the forward model of electrical impedance tomography (EIT) of brain function appears to improve image reconstruction, the generation of patient-specific finite element meshes has been the subject of much recent work. This paper presents a more rapid method of generating more geometrically accurate finite element meshes of the human head by warping existing meshes such that the surface boundary beneath the electrodes closely matches that of the subject with minimal degradation to the quality of the mesh. Pre-existing meshes of spheres and adult head models incorporating key internal anatomical features are warped, using elastic deformation, to match a phantom latex tank incorporating a real skull. The algorithm is described and tests are carried out to optimize the key parameters to ensure minimal degradation of mesh quality and distortion of internal features. Results show that the algorithm operating with the optimum parameters produces meshes of sound quality and could represent an important step in the timely and productive creation of forward models in clinical applications.
由于在脑功能电阻抗断层成像（EIT）的正向模型中使用逼真的几何形状似乎可以改善图像重建，因此生成患者特异性有限元网格成为近期许多工作的主题。本文提出了一种更快速的方法，通过对现有网格进行变形，生成几何形状更精确的人体头部有限元网格，使电极下方的表面边界与受试者的边界紧密匹配，同时网格质量的下降最小。利用弹性变形对包含关键内部解剖特征的球体和成人头部模型的现有网格进行变形，以匹配包含真实颅骨的幻影乳胶罐。描述了该算法并进行了测试，以优化关键参数，确保网格质量的下降最小和内部特征的失真最小。结果表明，以最佳参数运行的算法产生的网格质量良好，可能代表了在临床应用中及时、高效地创建正向模型的重要一步。
