Zhai Fei, Nan Qun, Ding Jinli, Xu Dehao, Zhang Huijuan, Liu Youjun, Bai Fan
College of Life Science and Bioengineering, Beijing University of Technology , Beijing , China.
Electromagn Biol Med. 2015 Mar;34(1):29-36. doi: 10.3109/15368378.2013.868813. Epub 2014 Jan 24.
The aim of this study is to investigate the thermal field distribution of phantom and ex vivo liver tissue in microwave ablation. We intent to verify if the phantom can be used in future studies in lieu of actual tissue.
This experiment was divided into two groups of phantom and ex vivo porcine liver tissue. 2450 MHz is set. The tests last up to 240 s in 60 W. The velocity of the circulating water pumps were adjusted to 40 rounds/min. Twenty-five copper-constantan thermocouples (TCs) were inserted at the specified position to record temperature data.
For the cooling water, the temperature field was non-symmetric distribution at the gap before (z > z < 0 mm) of two groups of experiments. At the part without cooling water (z > 0 mm), effective ablation areas were larger; near the microwave antenna, the temperature curves showed good consistency for both materials. Far away from the microwave antenna, the value difference increased between phantom and liver tissue. Moreover, the effect of cooling water in phantom is more obvious than it in liver tissue. The shapes of ablation areas from two groups are not same.
The result of the present work implied that heating patterns of liver tissue and phantom are comparable. But the difference of temperature field between two kinds of materials cannot be ignored. In cases of using phantom to verify temperature field in lieu of actual tissue, the researchers should pay full attention to these difference points.
本研究旨在探究微波消融中体模和离体肝组织的热场分布。我们试图验证该体模在未来研究中是否可替代实际组织使用。
本实验分为体模和离体猪肝组织两组。设定频率为2450 MHz。测试在60 W功率下持续240 s。将循环水泵的速度调至40转/分钟。在指定位置插入25个铜-康铜热电偶（TCs）以记录温度数据。
对于冷却水，在两组实验中，间隙处（z > z < 0 mm）的温度场呈非对称分布。在无冷却水的部分（z > 0 mm），有效消融面积更大；在微波天线附近，两种材料的温度曲线显示出良好的一致性。远离微波天线时，体模和肝组织之间的数值差异增大。此外，体模中冷却水的作用比肝组织中更明显。两组的消融区域形状不同。
本研究结果表明肝组织和体模的加热模式具有可比性。但两种材料之间的温度场差异不可忽视。在使用体模替代实际组织验证温度场的情况下，研究人员应充分关注这些差异点。
