Coagulated region analysis in a microwave surgical device with temperature-dependent physical properties of tissue

Abstract

In surgical devices, it is pointed out that tissues around these devices may experience thermal damage (coagulation). Therefore, evaluating the coagulated region generated by a microwave surgical device is an important issue. In this paper, we estimate the distribution of the coagulated region using numerical calculation. Then, there is a possibility that the calculated results will be affected by change to the electrical and thermal constants during heating. Therefore, the temperature dependence of the tissue was considered. As a result, it was confirmed that the coagulation width at the center of the lower blade was 0.5 mm larger than that without temperature dependence.

A review of antenna designs for percutaneous microwave ablation

“…where ε r is the relative permittivity of biologic tissue, σ c (S/m) is the electrical conductivity, ω (rad/s) is the angular frequency and ε 0 is the permittivity of vacuum. It has been found that the relative permittivity and electrical conductivity of biological tissues are dependent on frequency, temperature, and water content [63][64][65]. Therefore, taking these factors into consideration is of critical importance to develop an accurate computer model for MWA.…”

Reaching Deeper: Absolute In Vivo Thermal Reading of Liver by Combining Superbright Ag2S Nanothermometers and In Silico Simulations

“…In these simulations we considered the thermal dependence of physical properties of the liver as previously reported in the literature. [36] While the physical and thermal properties of the surrounding tissues were the ones included in the IT'IS Foundation database, [37] the physical properties of the liver were modified according to Manago et al [38] More details can be found in Section S3 of Supporting Information. Figure 5b shows the dependence of 𝜏 relax as a function of the total variation of temperature during cooling (ΔT liver ).…”

Characteristics of an antenna generating a localized heating region for robotic surgery

“…However, microwave energy generates large heating region generally [24]. In robotic surgery, localized heating is desirable to avoid damaging the surrounding tissues [25]- [28]. From these backgrounds, we proposed a double-loop antenna for miniaturization and generation of localized heating.…”