A high frequency electrical impedance tomograph using distributed parallel input channels.

J Jossinet; C Trillaud; F Risacher; E T McAdams

PubMed · 8052171

A high frequency electrical impedance tomograph using distributed parallel input channels.

J Jossinet·C Trillaud·F Risacher·E T McAdams

Abstract

Electrical Impedance Tomography (EIT) is an imaging technique based on multiple impedance measurements using electronically multiplexed surface electrodes. The present study describes an EIT prototype tomograph which uses two frequencies of applied signal: 31.25 kHz (within the frequency range originally used in early EIT studies) and 250 kHz. The use of the latter frequency was made possible as a result of several technical innovations including the use of separate groups of electrodes for current injection and for differential voltage measurement and the use of parallel input channels distributed around the object. In vitro images were successfully obtained using the system at the above two frequencies. It is concluded from this study that Electrical Impedance Tomography can be used at sufficiently high frequencies to enable bio-electrical tissue characterisation.

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Electric Conductivity Electric Impedance Electrodes Equipment Design Image Processing, Computer-Assisted Models, Structural Signal Processing, Computer-Assisted Tomography Journal Article Research Support, Non-U.S. Gov't

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J Jossinet, C Trillaud, F Risacher, E T McAdams. A high frequency electrical impedance tomograph using distributed parallel input channels.. https://pubmed.ncbi.nlm.nih.gov/8052171/

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