Kao Tzu-Jen, Kim Bong Seok, Isaacson D, Newell J C, Saulnier G J
Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180-3590, USA.
Physiol Meas. 2006 May;27(5):S13-23. doi: 10.1088/0967-3334/27/5/S02. Epub 2006 Apr 18.
Electrical impedance tomography (EIT) is a non-invasive technique used to image the electrical conductivity and permittivity within a body from measurements taken on the body's surface. High-quality static images are required for many medical imaging applications. Forming such images usually requires an accurate way to calculate the expected voltages on the surface resulting from the application of known currents to that surface. This is described as the forward problem. This paper introduces a new method to improve static images by using an improved forward solution which estimates a different conductivity value for each applied current pattern. This method, creating an automatically adjusting forward solution, can improve the sensitivity of static images under many EIT imaging applications. It does so by reducing the boundary effects caused by electrodes and any layered structures near them such as skin. The drawback of this method is that circularly symmetric structures of interest may be suppressed or eliminated from the images. The performance of this method is illustrated in a 2D circular phantom with simulation data from both a FEM model and experimental data.
电阻抗断层成像（EIT）是一种非侵入性技术，用于根据在人体表面进行的测量来成像人体内部的电导率和电容率。许多医学成像应用都需要高质量的静态图像。形成这样的图像通常需要一种准确的方法来计算在向该表面施加已知电流时表面上的预期电压。这被称为正向问题。本文介绍了一种新方法，通过使用改进的正向解来改善静态图像，该正向解为每个施加的电流模式估计不同的电导率值。这种创建自动调整正向解的方法可以提高许多EIT成像应用下静态图像的灵敏度。它通过减少由电极及其附近的任何分层结构（如皮肤）引起的边界效应来实现。该方法的缺点是感兴趣的圆形对称结构可能会从图像中被抑制或消除。在具有来自有限元模型的模拟数据和实验数据的二维圆形模型中展示了该方法的性能。
