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

为治疗深部肿瘤，研制了一种折返式腔谐振腔热疗系统。我们证实了对8厘米厚的体模进行集中加热是可能的。我们为15 cm厚的体模制作了一个更大的再入腔谐振器，但加热体模的中心导致了失败。为了解决这个问题，在模体上安装了两个金属盘(场集中装置)。该方法取得了良好的集中加热效果。有两种类型的加热模式：一种是圆柱形的，另一种是全局的。我们建立了一种确定频率的方法来获得任何时刻的柱状加热模式，但全局加热模式仍有可能通过进一步的研究来实现。所有结果都是从热像仪中获取的。通过有限元数值分析，也证实了再入腔谐振腔加热法优于通常的射频加热法。尤其是具有两个场聚焦装置的折返式腔谐振腔加热器的加热方法可用于加热深部肿瘤。必须检查以下主题：1)为了加热具有相似临床条件的25厘米厚的体模，必须开发更大的再入腔敷贴器，并且必须测量加热模式。2)必须引入与人体电学系数和结构相似的精心制作的体模来评价其热特性。

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.