Design of a microscopic electrical impedance tomography system using two current injections

Qin Liu, Tong In Oh, Hun Wi, Eun Jung Lee, Jin Keun Seo, Eung Je Woo

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

We describe a novel design of a microscopic electrical impedance tomography (micro-EIT) system for long-term noninvasive monitoring of cell or tissue cultures. The core of the micro-EIT system is a sample container including two pairs of current-injection electrodes and 360 voltage-sensing electrodes. In designing the container, we took advantage of a hexagonal structure with fixed dimensions and electrode configuration. This eliminated technical difficulties related to the unknown irregular boundary geometry of an imaging object in conventional medical EIT. Attaching a pair of large current-injection electrodes fully covering the left and right sides of the hexagonal container, we generated uniform parallel current density inside the container filled with saline. The 360 voltage-sensing electrodes were placed on the front, bottom and back sides of the hexagonal container in three sets of 8 × 15 arrays with equal gaps between them. We measured voltage differences between all neighboring pairs along the direction of the parallel current pathway. For the homogeneous container, all measured voltages must be the same since the voltage changes linearly along that direction. Any anomaly in the container perturbed the current pathways and therefore equipotential lines to produce different differential voltage data. For conductivity image reconstructions, we adopted a lately developed image reconstruction algorithm for this electrode configuration to first produce projected conductivity images on the front, bottom and back sides. Using a backprojection method, we reconstructed three-dimensional conductivity images from those projection images. To improve the image quality and also to meet the mathematical requirement on the uniqueness of a reconstructed image, we used a second pair of thin and long current-injection electrodes located at the middle of the front and back sides. This paper describes the design and construction of such a micro-EIT system with experimental results. Proposing the novel micro-EIT system design, we suggest future studies of miniaturizing the sample container for true microscopic conductivity imaging of cell or tissue cultures.

Original languageEnglish
Article number011
Pages (from-to)1505-1516
Number of pages12
JournalPhysiological measurement
Volume32
Issue number9
DOIs
Publication statusPublished - 2011 Sep 1

Fingerprint

Acoustic impedance
Electric Impedance
Tomography
Containers
Electrodes
Injections
Electric potential
Computer-Assisted Image Processing
Tissue culture
Image reconstruction
Cell culture
Three-Dimensional Imaging
Imaging techniques
Image quality
Current density
Systems analysis
Geometry
Monitoring

All Science Journal Classification (ASJC) codes

  • Biophysics
  • Physiology
  • Biomedical Engineering
  • Physiology (medical)

Cite this

@article{df2931242e78464b938582465b8ef325,
title = "Design of a microscopic electrical impedance tomography system using two current injections",
abstract = "We describe a novel design of a microscopic electrical impedance tomography (micro-EIT) system for long-term noninvasive monitoring of cell or tissue cultures. The core of the micro-EIT system is a sample container including two pairs of current-injection electrodes and 360 voltage-sensing electrodes. In designing the container, we took advantage of a hexagonal structure with fixed dimensions and electrode configuration. This eliminated technical difficulties related to the unknown irregular boundary geometry of an imaging object in conventional medical EIT. Attaching a pair of large current-injection electrodes fully covering the left and right sides of the hexagonal container, we generated uniform parallel current density inside the container filled with saline. The 360 voltage-sensing electrodes were placed on the front, bottom and back sides of the hexagonal container in three sets of 8 × 15 arrays with equal gaps between them. We measured voltage differences between all neighboring pairs along the direction of the parallel current pathway. For the homogeneous container, all measured voltages must be the same since the voltage changes linearly along that direction. Any anomaly in the container perturbed the current pathways and therefore equipotential lines to produce different differential voltage data. For conductivity image reconstructions, we adopted a lately developed image reconstruction algorithm for this electrode configuration to first produce projected conductivity images on the front, bottom and back sides. Using a backprojection method, we reconstructed three-dimensional conductivity images from those projection images. To improve the image quality and also to meet the mathematical requirement on the uniqueness of a reconstructed image, we used a second pair of thin and long current-injection electrodes located at the middle of the front and back sides. This paper describes the design and construction of such a micro-EIT system with experimental results. Proposing the novel micro-EIT system design, we suggest future studies of miniaturizing the sample container for true microscopic conductivity imaging of cell or tissue cultures.",
author = "Qin Liu and Oh, {Tong In} and Hun Wi and Lee, {Eun Jung} and Seo, {Jin Keun} and Woo, {Eung Je}",
year = "2011",
month = "9",
day = "1",
doi = "10.1088/0967-3334/32/9/011",
language = "English",
volume = "32",
pages = "1505--1516",
journal = "Physiological Measurement",
issn = "0967-3334",
publisher = "IOP Publishing Ltd.",
number = "9",

}

Design of a microscopic electrical impedance tomography system using two current injections. / Liu, Qin; Oh, Tong In; Wi, Hun; Lee, Eun Jung; Seo, Jin Keun; Woo, Eung Je.

In: Physiological measurement, Vol. 32, No. 9, 011, 01.09.2011, p. 1505-1516.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Design of a microscopic electrical impedance tomography system using two current injections

AU - Liu, Qin

AU - Oh, Tong In

AU - Wi, Hun

AU - Lee, Eun Jung

AU - Seo, Jin Keun

AU - Woo, Eung Je

PY - 2011/9/1

Y1 - 2011/9/1

N2 - We describe a novel design of a microscopic electrical impedance tomography (micro-EIT) system for long-term noninvasive monitoring of cell or tissue cultures. The core of the micro-EIT system is a sample container including two pairs of current-injection electrodes and 360 voltage-sensing electrodes. In designing the container, we took advantage of a hexagonal structure with fixed dimensions and electrode configuration. This eliminated technical difficulties related to the unknown irregular boundary geometry of an imaging object in conventional medical EIT. Attaching a pair of large current-injection electrodes fully covering the left and right sides of the hexagonal container, we generated uniform parallel current density inside the container filled with saline. The 360 voltage-sensing electrodes were placed on the front, bottom and back sides of the hexagonal container in three sets of 8 × 15 arrays with equal gaps between them. We measured voltage differences between all neighboring pairs along the direction of the parallel current pathway. For the homogeneous container, all measured voltages must be the same since the voltage changes linearly along that direction. Any anomaly in the container perturbed the current pathways and therefore equipotential lines to produce different differential voltage data. For conductivity image reconstructions, we adopted a lately developed image reconstruction algorithm for this electrode configuration to first produce projected conductivity images on the front, bottom and back sides. Using a backprojection method, we reconstructed three-dimensional conductivity images from those projection images. To improve the image quality and also to meet the mathematical requirement on the uniqueness of a reconstructed image, we used a second pair of thin and long current-injection electrodes located at the middle of the front and back sides. This paper describes the design and construction of such a micro-EIT system with experimental results. Proposing the novel micro-EIT system design, we suggest future studies of miniaturizing the sample container for true microscopic conductivity imaging of cell or tissue cultures.

AB - We describe a novel design of a microscopic electrical impedance tomography (micro-EIT) system for long-term noninvasive monitoring of cell or tissue cultures. The core of the micro-EIT system is a sample container including two pairs of current-injection electrodes and 360 voltage-sensing electrodes. In designing the container, we took advantage of a hexagonal structure with fixed dimensions and electrode configuration. This eliminated technical difficulties related to the unknown irregular boundary geometry of an imaging object in conventional medical EIT. Attaching a pair of large current-injection electrodes fully covering the left and right sides of the hexagonal container, we generated uniform parallel current density inside the container filled with saline. The 360 voltage-sensing electrodes were placed on the front, bottom and back sides of the hexagonal container in three sets of 8 × 15 arrays with equal gaps between them. We measured voltage differences between all neighboring pairs along the direction of the parallel current pathway. For the homogeneous container, all measured voltages must be the same since the voltage changes linearly along that direction. Any anomaly in the container perturbed the current pathways and therefore equipotential lines to produce different differential voltage data. For conductivity image reconstructions, we adopted a lately developed image reconstruction algorithm for this electrode configuration to first produce projected conductivity images on the front, bottom and back sides. Using a backprojection method, we reconstructed three-dimensional conductivity images from those projection images. To improve the image quality and also to meet the mathematical requirement on the uniqueness of a reconstructed image, we used a second pair of thin and long current-injection electrodes located at the middle of the front and back sides. This paper describes the design and construction of such a micro-EIT system with experimental results. Proposing the novel micro-EIT system design, we suggest future studies of miniaturizing the sample container for true microscopic conductivity imaging of cell or tissue cultures.

UR - http://www.scopus.com/inward/record.url?scp=80052100609&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80052100609&partnerID=8YFLogxK

U2 - 10.1088/0967-3334/32/9/011

DO - 10.1088/0967-3334/32/9/011

M3 - Article

C2 - 21828912

AN - SCOPUS:80052100609

VL - 32

SP - 1505

EP - 1516

JO - Physiological Measurement

JF - Physiological Measurement

SN - 0967-3334

IS - 9

M1 - 011

ER -