Towards magnetic detection electrical impedance tomography: data acquisition and image reconstruction of current density in phantoms and in vivo

Physiol Meas. 2004 Jun;25(3):775-96. doi: 10.1088/0967-3334/25/3/016.

Abstract

The objective of magnetic detection electrical impedance tomography (MD-EIT) is to reconstruct in vivo images of conductivity from magnetic field measurements taken around the body. MD-EIT is performed by applying an alternating current, at one of a range of frequencies, to a conducting object through a pair of electrodes fixed to the surface of the object. Magnetic field measurements recorded by search coils at a number of positions around the object are used to determine the current distribution that is generating the magnetic field. From this distribution, a conductivity map of a cross-section of the object can be reconstructed. This paper describes the development of an MD-EIT data acquisition system and discusses the related image reconstruction issues. The ill-conditioned nature of the inverse problem is examined and a number of image reconstruction methods are compared. The technical feasibility of MD-EIT data collection and image reconstruction is demonstrated with example images of current density from both phantom and human data.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Algorithms*
  • Electric Impedance*
  • Equipment Design
  • Equipment Failure Analysis
  • Feasibility Studies
  • Humans
  • Image Interpretation, Computer-Assisted / methods*
  • Information Storage and Retrieval / methods
  • Magnetics* / instrumentation
  • Software
  • Thorax / anatomy & histology*
  • Thorax / physiology*
  • Tomography / methods*