Temperature dependent dielectric spectroscopy of muscle tissue phantom

Abstract

The temperature dependence of the dielectric parameters of tissues and tissue-mimicking phantoms is very important for non-invasive temperature measurement in medical applications using microwaves. We performed measurements of this dependence in the temperature range of 25–50°C using distilled water as a reference liquid commonly used in dielectric property studies. The results were compared with the literature model in the frequency range of 150–3000 MHz. Using this method, the temperature dependence of dielectric parameters of a new muscle tissue-mimicking phantom based on agar, polyethylene powder, and polysaccharide material TX-151 was measured in the temperature range of 25–50°C. The temperature dependence of the dielectric properties of this new muscle phantom was fitted to that of the two-pole Cole–Cole model and the deviation of the results between measured and modeled data was quantified.

Application of an artificial intelligence segmentation for deep hyperthermia treatment planning in the pelvic region

“…Detailed models also allow more accurate simulation guided design of HT devices using, for example, meta-material structures or compact antenna structures [31][32][33]. Furthermore, this technology might also enable the creation of more complex anthropomorphic phantoms for hyperthermia quality control measurements including dielectric properties of specific phantom materials [34][35][36]. In clinical practice, dielectric properties can be obtained individually for every patient using electric property tomography, which uses magnetic resonance imaging (MRI) scanner [37,38].…”

Experimental Wireless Link and SAR Assessments of an Implantable PIFA for Biotelemetry in the 2.45 GHz Band

“…Degradations of the gains are expected when comparing simulations and measurements in this configuration due to the thick (60 mm) phantom used in measurements. Another possible reason is due to the discrepancy of the properties of the phantom which was measured at room temperature of 22 o C. During the radiation pattern measurements, the phantom may be slightly colder than 22 o C (due to laboratory conditions), affecting the properties of the phantom [50]. Besides the large difference in phantom size, the simulated realized gain for the antenna in C3 is observed to be lower than C2 due to possibly larger amounts of energy being absorbed by the four-layer phantom.…”