Medical and Biological Engineering and Computing

, Volume 32, Issue 5, pp 530–536 | Cite as

Finite-element method in electrical impedance tomography

  • E. J. Woo
  • P. Hua
  • J. G. Webster
  • W. J. Tompkins
Medical Physics and Imaging


In electrical impedance tomography (EIT), current patterns are injected into a subject and boundary voltages are measured to reconstruct a cross-sectional image of resistivity distribution. Static EIT image reconstruction requires a computer model of a subject, an efficient data-collection method and robust and fast reconstruction algorithms. The finite-element method is used as the computer model. The paper describes 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 mesh-design tools, including automatic mesh generation and optimisation using the Delaunay algorithm. Even though the software package is customised for use in electrical impedance tomography, it can be used for other biomedical research areas, such as impedance cardiography, cardiac defibrillation and impedance pneumography.


Electrical impedance tomography Finite-element method 


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Copyright information

© IFMBE 1994

Authors and Affiliations

  • E. J. Woo
    • 1
  • P. Hua
    • 2
  • J. G. Webster
    • 3
  • W. J. Tompkins
    • 3
  1. 1.Department of Biomedical Engineering, College of MedicineKon Kuk UniversityChoongbukKorea
  2. 2.Applied Research GroupSiemens Gammasonics Inc.Hoffman EstatesUSA
  3. 3.Department of Electrical and Computer EngineeringUniversity of Wisconsin-MadisonMadisonUSA

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