Three-dimensional image reconstruction for electrical impedance tomography

Analytical solution to the three-dimensional electrical forward problem for an elliptical cylinder

In electrical impedance tomography, the shape of the object being imaged (such as the human thorax) is often complex. For this reason, numerical techniques, such as finite element method, are often used for solving the forward problem in 3D rather than analytical solutions which can only model simple geometrical shapes. However, an analytical solution to the 3D forward problem can often be useful. This paper will present an analytical solution to the forward problem for an elliptical cylinder whose eccentricity can be easily modified to approximate the shape of the human thorax.

Impedance mammograph 3D phantom studies

The results obtained using the Technical University of Gdansk Electroimpedance Mammograph (TUGEM) of a 3D phantom study are presented. The TUGEM system is briefly described. The hardware contains the measurement head and DSP-based identification modules controlled by a PC computer. A specially developed reconstruction algorithm, Regulated Correction Frequency Algebraic Reconstruction Technique (RCFART), is used to obtain 3D images. To visualize results, the Advance Visualization System (AVS) is used. It allows a powerful image processing on a fast workstation or on a high-performance computer. Results of three types of 3D conductivity perturbations used in the study (aluminum, Plexiglas, and cucumber) are shown. The relative volumes of perturbations less than 2% of the measurement chamber are easily evidenced.