Hyperthermia System with Re-Entrant Cavity Applicator for Deep Seated Tumor.

针对深部肿瘤的热疗，研制了一种再入式谐振腔热疗系统.我们证实了对8 cm厚体模的集中加热是可能的。我们为15 cm厚的体模制作了一个较大的凹腔谐振器，但加热体模的中心导致失败。为了解决这个问题，两个金属盘（场集中装置）连接在体模上。这种方法带来了很好的集中加热效果.两种加热模式：一种是圆柱形的，另一种是全球性的。我们建立了一种确定频率的方法，以获得圆柱形加热模式在所有的时间，但全球加热模式可以实现进一步的研究。所有结果均来自热成像仪。通过有限元数值分析，也证实了凹腔谐振器加热方法优于通常的射频加热方法上级。特别是使用具有两个场集中装置的凹腔谐振器施加器的加热方法可以用于加热深层肿瘤.必须检查以下主题：1）为了加热具有相似临床条件的25 cm厚体模，必须开发更大的凹腔施源器，并且必须测量加热模式。2)必须引入一个与人体相似的电系数和结构的精细体模来评估加热特性。

For treatment of deep seated tumor a hyperthermia system with re-entrant cavity resonator was developed.1. We confirmed concentrated heating for 8 cm thickness phantom was possible.2. We fabricated a larger re-entrant cavity resonator for 15 cm thickness phantom but heating the center of the phantom was resulted in failure. To solve this problem two metal disks (field concentrating devices) were attached on the phantom. This method brought excellent results of concentrated heating.3. Two types of heating pattern : one is cylindrical and the other is global. We established a method of determining a frequency to obtain cylindrical heating pattern at all times, but the global heating pattern may be realized with further research. All results are taken from the thermo-camera.4. Through numerical analysis with finite element method it is also confirmed the heating method with re-entrant cavity resonator applicator is superior to the usual RF heating method. Especially the heating method with the re-entrant cavity resonator applicator having two field concentrating devicesmay serve to heat deep seated tumor.5. The following themes must be examined : 1) In order to heat a 25 cm thickness phantom of similar clinical condition a larger re-entrant cavity applicator must be developed and heating pattern must be measured. 2) A elaborate phantom with similar electric coefficient and structure as human body must be introduced to evaluate the heating characteristics.