Incorporating a Spatial Prior into Nonlinear D-Bar EIT Imaging for Complex Admittivities.
Incorporating a Spatial Prior into Nonlinear D-Bar EIT Imaging for Complex Admittivities.
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DOI：
10.1109/tmi.2016.2613511
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发表时间：
2017-02
影响因子：
10.6
通讯作者：
Alsaker M
中科院分区：
文献类型：
--
作者：
Hamilton SJ;Mueller JL;Alsaker M
电阻抗断层成像（EIT）的目的是恢复的内部电导率和介电常数分布的身体表面上的电极上采取的电气测量。重建任务是一个严重不适定的非线性反问题，是高度敏感的测量噪声和建模误差。正则化的D-杆方法通过对EIT问题的非线性（非物理）傅里叶变换数据进行低通滤波，在产生抗噪声算法方面表现出很大的希望。在散射变换中包括具有主要器官边界的近似位置的先验数据提供了一种扩展低通滤波器的半径以在重建中包括较高频率分量的手段，特别是以高置信度已知的特征。该信息另外包括在具有独立于扩展散射变换的正则化参数的D-bar方程系统中。在本文中，这种方法被用于2-D的D-bar方法的导纳（电导率以及介电常数）EIT成像。噪声鲁棒重建的模拟EIT数据与模拟气胸和胸腔积液的胸部形状的幻影。在先验的构建中没有使用病理学的假设，然而即使在存在强噪声的情况下，该方法仍然产生潜在病理学（气胸或胸腔积液）的显著增强。
Electrical Impedance Tomography (EIT) aims to recover the internal conductivity and permittivity distributions of a body from electrical measurements taken on electrodes on the surface of the body. The reconstruction task is a severely ill-posed nonlinear inverse problem that is highly sensitive to measurement noise and modeling errors. Regularized D-bar methods have shown great promise in producing noise-robust algorithms by employing a low-pass filterin of nonlinear (nonphysical) Fourier transform data specifi to the EIT problem. Including prior data with the approximate locations of major organ boundaries in the scattering transform provides a means of extending the radius of the low-pass filte to include higher frequency components in the reconstruction, in particular, features that are known with high confidence This information is additionally included in the system of D-bar equations with an independent regularization parameter from that of the extended scattering transform. In this paper, this approach is used in the 2-D D-bar method for admittivity (conductivity as well as permittivity) EIT imaging. Noise-robust reconstructions are presented for simulated EIT data on chest-shaped phantoms with a simulated pneumothorax and pleural effusion. No assumption of the pathology is used in the construction of the prior, yet the method still produces significant enhancements of the underlying pathology (pneumothorax or pleural effusion) even in the presence of strong noise.