FINITE-ELEMENT METHOD IN ELECTRICAL-IMPEDANCE TOMOGRAPHY

In electrical impedance tomography (EIT), current patterns are injecte d into a subject and boundary voltages are measured to reconstruct a c ross-sectional image of resistivity distribution. Static EIT image rec onstruction requires a computer model of a subject, an efficient data- collection method and robust and fast reconstruction algorithms. The f inite-element method is used as the computer model. The paper describe s the finite-element analysis software package developed, including an interactive graphical mesh generator and fast algorithms for solving linear systems of equations using sparse-matrix and vector techniques. Various models of irregularly shaped subjects are developed using mes h-design tools, including automatic mesh generation and optimisation u sing the delaunay algorithm. Even though the software package is custo mised for the use in electrical impedance tomography, it can be used f or other biomedical research areas, such as impedance cardiography, ca rdiac defibrillation and impedance pneumography.