The Research On Improvement Of Spatial Resolution Of Breast EIT

Electrical impedance tomography is a novel biomedical imaging technology. It is to obtainthe internal conductivity distribution of a bounded domain by measuring the surface voltageswhile injecting current into the target domain. Based on the significant difference conductivitybetween malignant tumors tissues and healthy breast tissues or benign tumors tissues, electricalimpedance tomography is used to obtain the conductivity distribution image of the breast tissue.First, the background significance and development of breast EIT are reviewed. Second,tri-prism elements in circular cylinder model are adopted for solving the forward problem by thefinite element method (FEM), the detailed derivation was introduced. In order to estimate theprecision of the numerical method, the analytical solution for a circular cylinder was used forcomparision in simulation. The potential errors of nodes were below3.57%. Third, the systemmatrix was constructed by the sensitive linear matrix method and TSVD and sLORETA methodswere applied for solving the inverse problem. According to the reconstructed results in thesimulation, the result by sLORETA is more convergent. Finally, in order to improve the spatialresolution, the theory and its computation steps of FOCUSS method are introduced and studiedand reconstructed images are obtained with higher spatial resolution.