A versatile and reproducible multi-frequency electrical impedance tomography system
File(s)sensors-17-00280-v2.pdf (2.16 MB)
Published version
OA Location
Author(s)
Avery, James
Dowrick, Thomas
Faulkner, Mayo
Goren, Nir
Holder, David
Type
Journal Article
Abstract
A highly versatile Electrical Impedance Tomography (EIT) system, nicknamed the ScouseTom, has been developed. The system allows control over current amplitude, frequency, number of electrodes, injection protocol and data processing. Current is injected using a Keithley 6221 current source, and voltages are recorded with a 24-bit EEG system with minimum bandwidth of 3.2 kHz. Custom PCBs interface with a PC to control the measurement process, electrode addressing and triggering of external stimuli. The performance of the system was characterised using resistor phantoms to represent human scalp recordings, with an SNR of 77.5 dB, stable across a four hour recording and 20 Hz to 20 kHz. In studies of both haeomorrhage using scalp electrodes, and evoked activity using epicortical electrode mats in rats, it was possible to reconstruct images matching established literature at known areas of onset. Data collected using scalp electrode in humans matched known tissue impedance spectra and was stable over frequency. The experimental procedure is software controlled and is readily adaptable to new paradigms. Where possible, commercial or open-source components were used, to minimise the complexity in reproduction. The hardware designs and software for the system have been released under an open source licence, encouraging contributions and allowing for rapid replication.
Date Issued
2017-02-01
Date Acceptance
2017-01-25
Citation
Sensors, 2017, 17 (2), pp.1-20
ISSN
1424-8220
Publisher
MDPI AG
Start Page
1
End Page
20
Journal / Book Title
Sensors
Volume
17
Issue
2
Copyright Statement
© 2017 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
License URL
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000395482700064&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Analytical
Engineering, Electrical & Electronic
Instruments & Instrumentation
Chemistry
Engineering
Electrical Impedance Tomography
brain imaging
long term monitoring
evoked activity
open source hardware
Arduino
FREQUENCY-DIFFERENCE EIT
ANESTHETIZED RAT
NEURAL ACTIVITY
BRAIN-FUNCTION
STROKE
CORTEX
MODEL
VALIDATION
PHANTOM
FMRI
Publication Status
Published
Article Number
ARTN 280
Date Publish Online
2017-01-31