Malone Emma, Sato Dos Santos Gustavo, Holder David, Arridge Simon
IEEE Trans Med Imaging. 2015 Jul;34(7):1486-1497. doi: 10.1109/TMI.2015.2402661. Epub 2015 Feb 11.
Multifrequency Electrical Impedance Tomography is an imaging technique which distinguishes biological tissues by their unique conductivity spectrum. Recent results suggest that the use of spectral constraints can significantly improve image quality. We present a combined reconstruction-classification method for estimating the spectra of individual tissues, whilst simultaneously reconstructing the conductivity. The advantage of this method is that a priori knowledge of the spectra is not required to be exact in that the constraints are updated at each step of the reconstruction. In this paper, we investigate the robustness of the proposed method to errors in the initial guess of the tissue spectra, and look at the effect of introducing spatial smoothing. We formalize and validate a frequency-difference variant of reconstruction-classification, and compare the use of absolute and frequency-difference data in the case of a phantom experiment.
多频电阻抗断层成像技术是一种通过生物组织独特的电导率谱来区分它们的成像技术。最近的结果表明，使用频谱约束可以显著提高图像质量。我们提出了一种联合重建-分类方法，用于估计各个组织的频谱，同时重建电导率。该方法的优点在于，频谱的先验知识不需要精确，因为在重建的每个步骤中都会更新约束条件。在本文中，我们研究了所提出的方法对组织频谱初始猜测误差的鲁棒性，并考察了引入空间平滑的效果。我们形式化并验证了重建-分类的频差变体，并在体模实验的情况下比较了绝对数据和频差数据的使用情况。
