433 MHz微波消融天线的设计与实验研究

Design and experimental research of microwave ablation antennas at the frequency of 433 MHz

目的针对915 MHz和2450 MHz微波在肝脏消融中穿透深度低及消融范围受限的问题,提出使用433 MHz微波用于恶性肝肿瘤的消融治疗,通过探索性研究和设计433 MHz频率的微波消融天线,探讨433 MHz微波消融系统对肝组织的消融效果。方法采用缝隙长度分别为18 mm、15 mm和15mm,缝隙间距为10 mm的尺寸设计天线。实时采集消融区域中4个不同旁开距离点的温度,并通过分析有效消融区域的横纵径数据,对所设计的微波天线进行有效评估。结果 433 MHz微波消融天线能形成类葫芦形的消融区域,不仅能有效扩大消融体积,而且能缩短最大横径形成的时间。结论 433 MHz微波消融天线有望应用于恶性肝肿瘤的微波热疗,为研究新频率段的适形微波消融方法提供重要参考。

Objective Due to the low penetration depth and the limited ablation range of 915 MHz and2450 MHz microwave in the ablation of the liver,we proposed to use 433 MHz microwave for ablation treatment of malignant liver tumors. The ablation effect of 433 MHz microwave ablation system on liver was investigated by means of exploratory research and design of the microwave ablation antenna at 433 MHz. Methods In the design of the antenna,the slot lengths were 18 mm,15 mm,15 mm,respectively,and the slot spacing was 10 mm. The temperatures of the four points with different side distances of ablation areas were recorded in real-time and this microwave antenna were evaluated effectively with the analysis of the transverse diameter and longitudinal diameter of the ablation areas. Results A gourd shaped ablation zone was formed with the microwave ablation antenna at the frequency of 433 MHz,which could not only expand the volume of the ablation zone,but also shorten the formation time of the maximum transverse diameter. Conclusions This 433 MHz microwave ablation antenna is promising for the application to the microwave hyperthermia of malignant liver tumor,which provides an important reference for the conformal microwave ablation method on the new frequency band.