In vivo EIT electrode system with 32 interlaced active electrodes

Li, J. H.; Joppek, C.; Faust, U.

doi:10.1007/bf02520083

Cited by 6 publications

(4 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore the influence of stray capacitance can be neglected. All electrodes are mounted together to form a multielectrode system (Li et al 1996) for in vivo measurements on the human thorax. This makes the attachment of electrodes very easy.…”

Section: Active Multielectrode Systemmentioning

confidence: 99%

Fast EIT data acquisition system with active electrodes and its application to cardiac imaging

Joppek

Faust

1996

Physiol. Meas.

View full text Add to dashboard Cite

A wide-band high-speed data acquisition system for electrical impedance tomography (EIT) is described. 32 active electrodes are used in the system, half of them as receive electrodes and the other half as drive electrodes. A buffer is mounted on the back of each receive electrode and a current source on each drive electrode. A multielectrode system with active electrodes was built to make it convenient to attach all the electrodes on the human thorax. The system is suitable for both dynamic imaging and multifrequency electrical impedance tomography (MFEIT). Its operating frequency can be chosen between 24 kHz and 400 kHz. Current is injected sequentially into 16 adjacent current electrode pairs and the 16 voltages between adjacent receive electrodes are measured for each current injection. ECG is collected to determine the relationship between the reconstructed images and cardiac activity. The collection of one frame of data is completed within 25 ms. The system has been successfully used for imaging the variation of conductivity distribution of the human thorax. The beat-by-beat cardiac-related change of conductivity distribution has been imaged by our system. The quasi-periodic variation of the impedance distribution can be seen from the image sequence with breath-holding.

show abstract

Section: Active Multielectrode Systemmentioning

confidence: 99%

Fast EIT data acquisition system with active electrodes and its application to cardiac imaging

Joppek

Faust

1996

Physiol. Meas.

View full text Add to dashboard Cite

show abstract

“…Guardo et al (1994) described a multiplexed active electrode system with an embedded micro-processor to manage the switches. This solution reduces the number of needed cables, compared with Li et al (1996aLi et al ( , 1996b, who emphasized the advantage using active electrodes instead of double-shielded passive cables. The latter are liable to cause instabilities and are inconveniently thick.…”

Section: Introductionmentioning

confidence: 99%

Electrical impedance tomography system based on active electrodes

et al. 2012

View full text Add to dashboard Cite

Abstract. EIT can image the distribution of ventilated lung tissue, and is thus a promising technology to help monitor patient breathing to help selection of mechanical ventilation parameters. Two key difficulties in EIT instrumentation make such monitoring difficult: 1) EIT data quality depends on good electrode contact and is sensitive to changes in contact quality, and 2) EIT electrodes are difficult and time consuming to place on patients. This paper presents the design and initial tests of an active electrode based system to address these difficulties. Our active electrode EIT system incorporates an active electrode belt, a central voltage driven current source, central ADCs and DACs, a central FPGA based demodulator and controller. The electrode belt is designed incorporating 32 active electrodes, each of which contains the electronic amplifiers, switches and associated logic. Tests show stable device performance with a convenient ease of use and good imaging ability in volunteer tests.

show abstract

“…A common application of bioelectrical impedance is in commercial body composition systems, such as the ImpSFB7® from ImpediMed, Inc. that computes the fat-to-muscle ratio of a person based on impedance measurements; it can also be used for evaluating lymphedema. Other applications include electrical impedance tomography, which uses an array of impedance measurements to create anatomical images of human body [2], [3]. …”

Section: Introductionmentioning

confidence: 99%

A portable system for the assessment of neuromuscular diseases with electrical impedance myography

Ogunnika

Rutkove

et al. 2010

Journal of Medical Engineering & Technology

View full text Add to dashboard Cite

Primary Objective To create a system for the acquisition of multi-angle, multifrequency muscle impedance data. Research Design Device development and preliminary testing. Methods and Procedures The system presented here employs an interrogating signal composed of multiple tones with frequencies between 10 kHz and 300 kHz. The use of a composite signal makes possible measurement of impedance at multiple frequencies simultaneously. In addition, this system takes impedance measurements at multiple orientations with respect to the muscle fibers by means of an electronically reconfigurable electrode array utilizing the linearity of muscle tissue to reduce the required measurement time. Main outcomes and results The system was tested in normal subjects, a patient with amyotrophic lateral sclerosis, and one with inclusion body myositis; unique impedance signatures were identified the two patients. Conclusions Early data suggests that this system is capable of high-quality data collection and may detect changes in neuromuscular disease; study of additional normal subjects and patients with a variety of neuro-muscular diseases is warranted.

show abstract

In vivo EIT electrode system with 32 interlaced active electrodes

Cited by 6 publications

References 4 publications

Fast EIT data acquisition system with active electrodes and its application to cardiac imaging

Fast EIT data acquisition system with active electrodes and its application to cardiac imaging

Electrical impedance tomography system based on active electrodes

A portable system for the assessment of neuromuscular diseases with electrical impedance myography

Contact Info

Product

Resources

About