Reproducible 3D printed head tanks for electrical impedance tomography with realistic shape and conductivity distribution
File(s)Avery_2017_Physiol._Meas._38_1116.pdf (2.98 MB)
Published version
Author(s)
Avery, J
Aristovich, K
Low, B
Holder, D
Type
Journal Article
Abstract
Objective. Electrical impedance tomography (EIT) has many promising applications in brain injury monitoring. To evaluate both instrumentation and reconstruction algorithms, experiments are first performed in head tanks. Existing methods, whilst accurate, produce a discontinuous conductivity, and are often made by hand, making it hard for other researchers to replicate. Approach. We have developed a method for constructing head tanks directly in a 3D printer. Conductivity was controlled through perforations in the skull surface, which allow for saline to pass through. Varying the diameter of the holes allowed for the conductivity to be controlled with 3% error for the target conductivity range. Taking CT and MRI segmentations as a basis, this method was employed to create an adult tank with a continuous conductivity distribution, and a neonatal tank with fontanelles. Main results. Using 3D scanning a geometric accuracy of 0.21 mm was recorded, equal to that of the precision of the 3D printer used. Differences of 6.1% ± 6.4% (n = 11 in 4 tanks) compared to simulations were recorded in c. 800 boundary voltages. This may be attributed to the morphology of the skulls increasing tortuosity effects and hole misalignment. Despite significant differences in errors between three repetitions of the neonatal tank, images of a realistic perturbation could still be reconstructed with different tanks used for the baseline and perturbation datasets. Significance. These phantoms can be reproduced by any researcher with access to a 'hobbyist' 3D printer in a matter of days. All design files have been released using an open source license to encourage reproduction and modification.
Date Issued
2017-05-22
Date Acceptance
2017-03-09
Citation
Physiological Measurement, 2017, 38 (6), pp.1116-1131
ISSN
0967-3334
Publisher
IOP Publishing
Start Page
1116
End Page
1131
Journal / Book Title
Physiological Measurement
Volume
38
Issue
6
Copyright Statement
© 2017 Institute of Physics and Engineering in Medicine. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
License URL
Subjects
Science & Technology
Life Sciences & Biomedicine
Technology
Biophysics
Engineering, Biomedical
Physiology
Engineering
electrical impedance tomography (EIT)
phantom
head tank
rapid prototyping
3D printing
realistic shape
BRAIN-FUNCTION
EIT
MODEL
PHANTOM
RECONSTRUCTION
STROKE
SKULL
VALIDATION
ANATOMY
SYSTEM
Biomedical Engineering
0903 Biomedical Engineering
0906 Electrical and Electronic Engineering
1116 Medical Physiology
Publication Status
Published