A 3D hybrid BE–FE solution to the forward problem of electrical impedance tomography

This paper presents a three dimensional (3D) hybrid boundary element–finite element (BE–FE) method solution to the electrical impedance tomography (EIT) forward problem. EIT is a method to find the distribution of electrical conductivity within an object through injecting current on surface electrodes placed on the object, and measuring the distribution of potential around the object. Existing 3D models are based on the finite element (FE) method and the boundary element (BE) method. In this paper, a hybrid BE–FE method approach is demonstrated for modeling the forward problem of EIT. Such a hybrid BE–FE technique combines strengths of FE and BE methods by dividing the regions into some homogeneous BE regions and heterogeneous FE regions. To validate numerical results, a homogenous test problem is solved analytically for the electrical potential. A cylindrical model of human thorax is studied. Results obtained for this model from BE, FE, and hybrid BE–FE methods with three different meshes and two different electrode placement strategies are compared.