Enhancing impedance imaging through multimodal tomography

Doğa Gürsoy, Yasin Mamatjan, Andy Adler, Hermann Scharfetter

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Several noninvasive modalities including electrical impedance tomography (EIT), magnetic induction tomography (MIT), and induced-current EIT (ICEIT) have been developed for imaging the electrical conductivity distribution within a human body. Although these modalities differ in how the excitation and detection circuitry (electrodes or coils) are implemented, they share a number of common principles not only within the image reconstruction approaches but also with respect to the basic principle of generating a current density distribution inside a body and recording the resultant electric fields. In this paper, we are interested in comparing differences between these modalities and in theoretically understanding the compromises involved, despite the increased hardware cost and complexity that such a multimodal system brings along. To systematically assess the merits of combining data, we performed 3-D simulations for each modality and for the multimodal system by combining all available data. The normalized sensitivity matrices were computed for each modality based on the finite element method, and singular value decomposition was performed on the resultant matrices. We used both global and regional quality measures to evaluate and compare different modalities. This study has shown that the condition number of the sensitivity matrix obtained from the multimodal tomography with 16-electrode and 16-coil is much lower than the condition number produced in the conventional 16-channel EIT and MIT systems, and thus, produced promising results in terms of image stability. An improvement of about 20% in image resolution can be achieved considering feasible signal-to-noise ratio levels.

Original languageEnglish
Pages (from-to)3215-24
Number of pages10
JournalIEEE transactions on biomedical engineering
Volume58
Issue number11
DOIs
Publication statusPublished - Nov 2011

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Tomography
Imaging techniques
Acoustic impedance
Electromagnetic induction
Electrodes
Induced currents
Singular value decomposition
Image resolution
Image reconstruction
Signal to noise ratio
Current density
Electric fields
Hardware
Finite element method
Costs

Keywords

  • Algorithms
  • Finite Element Analysis
  • Magnetics
  • Phantoms, Imaging
  • Plethysmography, Impedance/methods
  • Signal Processing, Computer-Assisted
  • Signal-To-Noise Ratio
  • Tomography/methods

Fields of Expertise

  • Human- & Biotechnology

Cite this

Enhancing impedance imaging through multimodal tomography. / Gürsoy, Doğa; Mamatjan, Yasin; Adler, Andy; Scharfetter, Hermann.

In: IEEE transactions on biomedical engineering, Vol. 58, No. 11, 11.2011, p. 3215-24.

Research output: Contribution to journalArticleResearchpeer-review

Gürsoy, Doğa ; Mamatjan, Yasin ; Adler, Andy ; Scharfetter, Hermann. / Enhancing impedance imaging through multimodal tomography. In: IEEE transactions on biomedical engineering. 2011 ; Vol. 58, No. 11. pp. 3215-24.
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