Investigation of biological phantom for 2D and 3D breast EIT images

Abstract

A biological phantom has been investigated for use with an Electrical Impedance Mammography (EIM) as developed by the Leicester Group. The phantom mimics the impedance property of human tissues as determined from in-vitro studies of breast tissues and can provide different impedance characteristics over the frequency range 1kHz-10MHz including the potential for a Beta dispersion. The work presented here is on those phantoms mimicking the electrical dielectric property of different breast tissues reported by others. Based on two types of phantoms, images have been produced within which "stroma" and "fat" regions can be easily distinguished. Image of "tumours", with diameters of 2-8mm, can be visualised at different imaging quality, depending background conductivity (hence age group), location of lesion as well as on other factors. The designed phantoms have provided vital information for the feasibility evaluation of on-going in-vivo EIM system based on the knowledge from both published results and the collected in vitro tissue data. Further work is ongoing to modify 3D phantoms in order to improve mimicry of conductivity spectra, and to permit the inclusion of a complete Beta dispersion. It is hoped that such phantoms will form the foundation to standard system calibration routines. © Springer-Verlag 2007.