Dielectric spectroscopy of liver mixture model for millimetre-wave imaging

Abstract

In this paper, we present a technique to mimic the dielectric properties for liver at 0.2-50 GHz based on the effective medium theory. A mathematical model based on Bruggeman mixture equation is presented to describe the dielectric properties of liver. The dielectric response of the mixture system considers two dielectric media, referred to as the host and inclusion media. In fact, proposed mixture solution consists of concentrations of Bovine Serum Albumin (BSA) in PBS solution, synthesized to mimic in-vivo liver tissue using physiological saline solutions coupled with protein additions. Generally, when testing an electromagnetic medical device in prototype phase, such solutions are required to assess the feasibility of the technology. The dielectric properties as measured experimentally are correlated to the calculated effective permittivity using Bruggemann equation. Results were then analysed, implying that such solutions can be utilised in the construction of human body phantoms for narrowband and ultra-wideband microwave devices for both millimeter-wave imaging and applications in hyperthermia and other ablation modalities. The frequency range studied could also lead to realistic phantoms for dosimetry studies related to human safety concerns. Hence, a stratified liver mixture model has been proposed which can be used as a theoretical basis for taking further steps in liver cancer research.