Finite-Element Analysis and In Vitro Experiments of Placement Configurations Using Triple Antennas in Microwave Hepatic Ablation

Abstract

This study presents analyses of triple-antenna configurations and designs for microwave (MW) hepatic ablation using 3-D finite-element (FE) analyses verified by in vitro experiments. Treatment of hepatic cancer often requires removal or destruction of large volume lesions. Using multiple antennas offers a potential solution for creating ablation zones with larger dimensions, as well as varied geometrical shapes. We performed both 3-D FE analyses and in vitro experiments using three identical open-tip MW antennas simultaneously, placing them in three types of configurations-"linear array," "triangular," and "T-shaped" arrangements. We compared coagulation volumes created, as well as temperature distribution characteristics, from the three-antenna arrangements after power delivery of 50 W for 60 s. We also performed additional tests using nonidentical antennas (open tip, slot, and slot with insulating jacket) for the three configurations. The results illustrate that arranging antennas in the "T-shaped" pattern destroyed more unwanted tissues than those found when using "linear array" and "triangular" arrangements, with maximum coagulation width and depth of 46 and 81 mm, respectively, and coagulation volume of 30.7 cm(3) . In addition, using nonidentical triple antennas caused variations in coagulation zone characteristics, and thus, the technique could be applied to treatment situations where nonsymmetric coagulation zones are required.

Multiple applicator hepatic ablation with interstitial ultrasound devices: Theoretical and experimental investigation

“…While the Pennes equation has limitations, particularly in accounting for heat transfer due to large blood vessels, it remains a reasonable approximation for modeling heat transfer in tissue and is widely used for evaluating performance of ablation technology. [47][48][49] Recent studies have validated the temperature and thermal damage profile computed using Pennes model with experiments in perfused ex vivo liver, as well as in vivo animal models. [49][50][51] The tissue acoustic and thermal properties used in the model for Eqs.…”

The Effect of Slot Sizes on Non-Asymmetry Slot Antennafor Microwave Coagulation Therapy

“…A nonuniform heating MW ablation system might be beneficial to properly ablated both regions close to large blood vessels (more heat) and those that are further away(less heat). In addition, optimal placement configurations by use Non-Asymmetry structure (open-slot one side) multiple antenna for MW ablation needs to be further explored as a recent study by [32].…”

“…We perform the analyses using 3D finite element modeling. same as [32]. For comparison of the results, we determine the SAR and temperature distributions in tissue generated by the antennas with different slot size.…”

Analysis of heat sink effect in hepatic cancer treatment near arterial for microwave ablation by using finite element method

“…The SAR show the heat generated by the electric field in the tissue given by In this study, we calculate SAR distributions for all cases and compare the results to determine the potential heating pattern of the antenna. The thermal and electrical properties used are from [7][8][9]. We can link the volume of SAR according to (3) as below.…”