Phantoms provide valuable test platforms for developing medical devices. Solid materials in particular allow fabrication of stable and robust models. This paper presents a novel, anatomically realistic, multi-layered head phantom made from dielectrically accurate, stable, easily mouldable, low-cost tissue-mimicking materials for testing of microwave diagnostic systems. Also incorporated is a mechanism for inserting reconfigurable lesions and a novel circulatory system modelling physiology. Tissue-mimicking materials composed of graphite, carbon black, and polyurethane with small volumes of acetone or isopropanol were fabricated and dielectric properties were measured across the 1 - 8.5 GHz band. The tissuemimicking material properties were adjusted until their dielectric properties matched those of reference values for target tissues of interest, thereby emulating: weighted aggregates of head tissues external to the brain, tissues comprising the brain, and blood. 3D printed anatomically realistic head and brain moulds cast the phantom mixtures for each layer. Cylindrical holes in the brain layer allow insertion of pathological lesion phantoms, such as haemorrhages. Tubing embedded in the brain layer forms a symmetrical loop providing a novel simplistic model of circulation. The resulting head phantom is anatomically realistic, dielectrically stable, enables pathology modelling, and has, uniquely, a circulatory loop. This novel head phantom provides a valuable test platform for microwave diagnostic studies.
2. Lee, B. and A. Newberg, "Neuroimaging in traumatic brain imaging," NeuroRX, Vol. 2, No. 2, 372-383, Apr. 2005.
3. Birenbaum, D., L. W. Bancroft, and G. J. Felsberg, "Imaging in acute stroke," West. J. Emerg. Med., Vol. 12, No. 1, 67-76, Feb. 2011.
4. Semenov, S., "Microwave tomography: Review of the progress towards clinical applications," Philos. Trans. A. Math. Phys. Eng. Sci., Vol. 367, 3021-3042, 2009.
5. Garrett, J. and E. Fear, "A new breast phantom with a durable skin layer for microwave breast imaging," IEEE Trans. Antennas Propag., Vol. 63, No. 4, 1693-1700, 2015.
6. Mobashsher, A. T. and A. M. Abbosh, "Artificial human phantoms: Human proxy in testing microwave apparatuses that have electromagnetic interaction with the human body," IEEE Microw. Mag., Vol. 16, No. 16, 42-62, 2015.
7. Fear, E. C., P. M. Meaney, and M. Stuchly, "Microwaves for breast cancer detection?," IEEE Potential, Vol. 22, No. 1, 12-18, Feb. 2003.
8. Garrett, J. and E. Fear, "Stable and flexible materials to mimic the dielectric properties of human soft tissues," IEEE Antennas Wirel. Propag. Lett., Vol. 13, 599-602, 2014.
9. Peyman, A., A. A. Rezazadeh, and C. Gabriel, "Changes in the dielectric properties of rat tissue as a function of age at microwave frequencies," Phys. Med. Biol., Vol. 46, No. 6, 1617-1629, Jun. 2001.
10. Kobayashi, T., T. Nojima, K. Yamada, and S. Uebayashi, "Dry phantom composed of ceramics and its application to SAR estimation," IEEE Trans. Microw. Theory Tech., Vol. 41, No. 1, 136-140, 1993.
11. Watanabe, S.-I., H. Taki, T. Nojima, and O. Fujiwara, "Characteristics of the SAR distributions in a head exposed to electromagnetic fields radiated by a hand-held portable radio," IEEE Trans. Microw. Theory Tech., Vol. 44, No. 10, 1874-1883, 1996.
12. Mobashsher, A. T. and A. M. Abbosh, "Three-dimensional human head phantom with realistic electrical properties and anatomy," IEEE Antennas Wirel. Propag. Lett., Vol. 13, 1401-1404, 2014.
13. Otterskog, M., N. Petrovic, and P. O. Risman, "A multi-layered head phantom for microwave investigations of brain hemorrhages," 2016 IEEE Conference on Antenna Measurements & Applications (CAMA), 1-3, 2016.
14. Santorelli, A., O. Laforest, E. Porter, and M. Popovi, "Image classification for a time-domain microwave radar system: Experiments with stable modular breast phantoms," European Conference on Antennas and Propagation (EuCAP), 2015.
15. Gabriel, C., S. Gabriel, and E. Corthout, "The dielectric properties of biological tissues: I. Literature survey," Phys. Med. Biol., Vol. 41, No. 11, 2231-49, 1996.
16. Gabriel, S., R. W. Lau, and C. Gabriel, "The dielectric properties of biological tissues: III. Parametric models for the dielectric spectrum of tissues," Phys. Med. Biol., Vol. 41, No. 11, 2271-93, 1996.
17. Hasgall, P., F. DiGennaro, C. Baumgartner, E. Neufeld, M. Gosselin, D. Payne, A. Klingenbock, and N. Kuster, "IT’IS Database for thermal and electromagnetic parameters of biological tissues,", 2015, [Online], Available: www.itis.ethz.ch/database, [Accessed: 25-Nov-2016].
18. Grozny, "Thingiverse --- Human Head,", [Online], Available: http://www.thingiverse.com/thing: 172348, [Accessed: 15-Feb-2017].
19. Dilmen, N., "NIH 3D print exchange --- Brain MRI,", [Online], Available: https://3dprint.nih.gov/discover/3DPX-002739, [Accessed: 15-Feb-2017].
20. Foster, K. R., J. L. Schepps, R. D. Stoy, and H. P. Schwan, "Dielectric properties of brain tissue between 0.01 and 10 GHz," Phys. Med. Biol., Vol. 24, No. 6, 1177-1187, 1979.
21. Schmid, G., G. Neubauer, and P. R. Mazal, "Dielectric properties of human brain tissue measured less than 10 h postmortem at frequencies from 800 to 2450 MHz," Bioelectromagnetics, Vol. 24, No. 6, 423-430, 2003.
22. Gabriel, C. and A. Peyman, "Dielectric measurement: Error analysis and assessment of uncertainty," Phys. Med. Biol., Vol. 51, No. 23, 6033-6046, 2006.
23. Pethig, R., "Dielectric properties of body tissues," Clin. Phys. Physiol. Meas., Vol. 8, No. Suppl A, 5-12, 1987.
24. Hyttinen, J., P. Kauppinen, T. Koobi, and J. Malmivuo, "Importance of the tissue conductivity values in modelling the thorax as a volume conductor," 19th Annu. Int. Conf. IEEE Eng. Med. Biol. Soc., Vol. 19, No. C, 2082-2085, 1997.
25. Gabriel, C., "Dielectric properties of biological tissue: Variation with age," Bioelectromagnetics, Vol. 26, No. SuppL. 7, 12-18, 2005.
26. Luders, E., H. Steinmetz, and L. Jancke, "Brain size and grey matter volume in the healthy human brain," Neuroreport, Vol. 13, No. 17, 2371-4, 2002.
27. Makris, N., L. Angelone, S. Tulloch, S. Sorg, J. Kaiser, D. Kennedy, and G. Bonmassar, Absorption Rate Mapping, Vol. 46, No. 12, 1239-1251, 2010.
28. Kim, D.-Y., R. Jung, H.-S. Kim, and H.-J. Jin, "Electrically conductive polymeric nanocomposites prepared in alcohol dispersion of multiwalled carbon nanotubes," Mol. Cryst. Liq. Cryst., Vol. 491, No. 1, 255-263, Sep. 2008.
29. Stokes, M. G., C. D. Chambers, I. C. Gould, T. R. Henderson, N. E. Janko, N. B. Allen, J. B. Mattingley, A. T. Barker, M. Dervinis, F. Verbruggen, L. Maizey, R. C. Adams, R. Henderson, and B. Jason, "Simple metric for scaling motor threshold based on scalp-cortex distance: Application to studies using transcranial magnetic stimulation simple metric for scaling motor threshold based on scalp-cortex distance: Application to studies using transcranial," J. Neurophysiol., Vol. 94, No. 6, 4520-7, 2005.
30. Standring, S., Gray’s Anatomy: The Anatomical Basis of Clinical Practice, 40th Ed., Elsevier, 2009.
31. Sims, J. R., L. R. Gharai, P. W. Schaefer, M. Vangel, E. S. Rosenthal, M. H. Lev, and L. H. Schwamm, "ABC/2 for rapid clinical estimate of infarct, perfusion, and mismatch volumes," Neurology, Vol. 72, No. 24, 2104-2110, 2009.
32. Mobashsher, A. T., K. S. Bialkowski, A. M. Abbosh, and S. Crozier, "Design and experimental evaluation of a non-invasive microwave head imaging system for intracranial haemorrhage detection," PLoS One, Vol. 11, No. 4, Apr. 2016.
33. Curry, R. A. and B. B. Tempkin, Sonography --- E-Book: Introduction to Normal Structure and Function, 3rd Ed., Saunders, 2014.