Broadband Dielectric Properties of Ex Vivo Bovine Liver Tissue Characterized at Ablative Temperatures

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21230%2F21%3A00341245" target="_blank" >RIV/68407700:21230/21:00341245 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1109/TBME.2020.2996825" target="_blank" >https://doi.org/10.1109/TBME.2020.2996825</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1109/TBME.2020.2996825" target="_blank" >10.1109/TBME.2020.2996825</a>

Result language

angličtina

Original language name

Broadband Dielectric Properties of Ex Vivo Bovine Liver Tissue Characterized at Ablative Temperatures

Original language description

Objective: To investigate the thermal and frequency dependence of dielectric properties of ex vivo liver tissue — relative permittivity and effective conductivity — over the frequency range of 500 MHz to 6 GHz and temperatures ranging from 20 to 130 °C. Methods: We measured the dielectric properties of fresh ex vivo bovine liver tissue using the open-ended coaxial probe method (n =15 samples). Numerical optimization techniques were utilized to obtain parametric models for characterizing changes in broadband dielectric properties as a function of temperature and thermal isoeffective dose. The effect of heating tissue at rates over the range 6.4—16.9 °C/min was studied. The measured dielectric properties were used in simulations of microwave ablation to assess changes in simulated antenna return loss compared to experimental measurements. Results: Across all frequencies, both relative permittivity and effective conductivity dropped sharply over the temperature range 89 — 107 °C. Below 91 °C, the slope of the effective conductivity changes from positive values at lower frequencies (0.5—1.64 GHz) to negative values at higher frequencies (1.64—6 GHz). The maximum achieved correlation values between transient reflection coefficients from measurements and simulations ranged between 0.83 — 0.89 and 0.68 — 0.91, respectively, when using temperature-dependent and thermal-dose dependent dielectric property parameterizations. Conclusion: We have presented experimental measurements and parametric models for characterizing changes in dielectric properties of bovine liver tissue at ablative temperatures. Significance: The presented dielectric property models will contribute to the development of ablation systems operating at frequencies other than 2.45 GHz, as well as broadband techniques for monitoring growth of microwave ablation zones.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10602 - Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology

Project

<a href="/en/project/EF16_019%2F0000765" target="_blank" >EF16_019/0000765: Research Center for Informatics</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

IEEE Transactions on Biomedical Engineering

ISSN

0018-9294

e-ISSN

1558-2531

Volume of the periodical

68

Issue of the periodical within the volume

1

Country of publishing house

US - UNITED STATES

Number of pages

9

Pages from-to

90-98

UT code for WoS article

000602691200010

EID of the result in the Scopus database

2-s2.0-85098588754