Optimal distance of multi-plane sensor in three-dimensional electrical impedance tomography

Abstract

Electrical impedance tomography (EIT) is a visual imaging technique for obtaining the conductivity and permittivity distributions in the domain of interest. As an advanced technique, EIT has the potential to be a valuable tool for continuously bedside monitoring of pulmonary function. The EIT applications in any three-dimensional (3 D) field are very limited to the 3 D effects, i.e. the distribution of electric field spreads far beyond the electrode plane. The 3 D effects can result in measurement errors and image distortion. An important way to overcome the 3 D effect is to use the multiple groups of sensors. The aim of this paper is to find the best space resolution of EIT image over various electrode planes and select an optimal plane spacing in a 3 D EIT sensor, and provide guidance for 3 D EIT electrodes placement in monitoring lung function. In simulation and experiment, several typical conductivity distribution models, such as one rod (central, midway and edge), two rods and three rods, are set at different plane spacings between the two electrode planes. A Tikhonov regularization algorithm is utilized for reconstructing the images; the relative error and the correlation coefficient are utilized for evaluating the image quality. Based on numerical simulation and experimental results, the image performance at different spacing conditions is evaluated. The results demonstrate that there exists an optimal plane spacing between the two electrode planes for 3 D EIT sensor. And then the selection of the optimal plane spacing between the electrode planes is suggested for the electrodes placement of multi-plane EIT sensor.

Drive and measurement electrode patterns for electrode impedance tomography (EIT) imaging of neural activity in peripheral nerve

“…It is common in biological applications of EIT to configure the drive and measurement electrodes on the same plane in a ring around the sample boundary, which is then expanded to 3D EIT by stacking several rings, or 2D imaging planes [8][9][10][11]. Where stacked rings are not practical, such as half ellipsoid on the head, drive and measurement pattern strategies are employed to target a region of interest [12][13][14][15][16] and maximise information produced [17].…”

A Multi-Frequency Focused Impedance Measurement System Based on Analogue Synchronous Peak Detection

“…Thus, the individual pixel values of the reconstructed image do not give an accurate value of the impedivity at that point in the medium. Several groups have undertaken efforts to obtain 3D EIT images having more of the above set of electrodes in several planes along the length of the cylinder (Ye et al, 2008;Hao et al, 2017;Zhang et al, 2019). However, reconstructing 3D EIT images is far more challenging than that for 2D images, and it will be quite some time before practically usable 3D EIT systems are developed for routine use.…”

Optimum reduction of sensing electrodes for delamination identification with electrical resistance tomography

“…More than one electrode plane can be used to account for the 3D effect on the reconstructed image (Figure 1a). Finding the best electrode plane location with respect of a reference level 18 or the optimum spacing between electrode planes 19 is necessary for accurate image reconstruction. Multiple planes of electrode rings are used to create a 3D image to detect malfunction in stirring vessels 20,21 .…”