Montreal Univ., Que.
IEEE Trans Med Imaging. 1994;13(4):594-600. doi: 10.1109/42.363109.
Reconstruction of images in electrical impedance tomography requires the solution of a nonlinear inverse problem on noisy data. This problem is typically ill-conditioned and requires either simplifying assumptions or regularization based on a priori knowledge. The authors present a reconstruction algorithm using neural network techniques which calculates a linear approximation of the inverse problem directly from finite element simulations of the forward problem. This inverse is adapted to the geometry of the medium and the signal-to-noise ratio (SNR) used during network training. Results show good conductivity reconstruction where measurement SNR is similar to the training conditions. The advantages of this method are its conceptual simplicity and ease of implementation, and the ability to control the compromise between the noise performance and resolution of the image reconstruction.
电阻抗断层成像中的图像重建需要对噪声数据进行非线性反问题求解。这个问题通常是病态的,需要简化假设或基于先验知识进行正则化。作者提出了一种使用神经网络技术的重建算法,该算法直接从正问题的有限元模拟中计算反问题的线性逼近。该逆问题适应于介质的几何形状和网络训练期间使用的信噪比(SNR)。结果表明,在测量 SNR 与训练条件相似的情况下,电导率重建效果良好。该方法的优点是概念简单,易于实现,并且能够控制图像重建的噪声性能和分辨率之间的折衷。