Ni Ansheng, Dong Xiuzhen, Yang Guosheng, Fu Feng, Tang Chi
Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, Shaanxi 710033, China.
Comput Med Imaging Graph. 2008 Jul;32(5):409-15. doi: 10.1016/j.compmedimag.2008.04.002. Epub 2008 May 23.
The structural similarity of the head model affects the accuracy of forward solution to electrical impedance tomography (EIT). Generally, the four-concentric circle model (FCCM) is used as the head model, which ignores the inhomogeneous distribution of the conductivity of real skull. In order to decrease the errors caused by using FCCM, a more accurate head model named inhomogeneous skull model (ISM) has been proposed and a reconstruction algorithm incorporated with ISM has been developed for brain EIT. Simulation results have shown improvement in image quality and localization accuracy when using ISM. It is also suggested that the reconstructed image could be more sensitive to the location of bony sutures than to the variation of skull thickness. In conclusion, incorporating skull inhomogeneity into image reconstruction is an effective way to improve image quality and localization accuracy for brain EIT.
头部模型的结构相似性会影响电阻抗断层成像（EIT）正向解的准确性。通常，四同心圆模型（FCCM）被用作头部模型，该模型忽略了真实颅骨电导率的非均匀分布。为了减少使用FCCM所导致的误差，已经提出了一种更精确的头部模型——非均匀颅骨模型（ISM），并且已经开发了一种与ISM相结合的用于脑部EIT的重建算法。仿真结果表明，使用ISM时图像质量和定位精度有所提高。还表明，重建图像对骨缝位置的敏感度可能高于对颅骨厚度变化的敏感度。总之，将颅骨的非均匀性纳入图像重建是提高脑部EIT图像质量和定位精度的有效方法。
