Basic Research on Identifing Location and Temperature of Cancer using the Measurement of Human Body Surface Impedance

通常进行手术和/或使用化学药物是治疗癌症的常用方法。近年来，热疗法在许多病例中得到应用。这种方法利用了癌细胞在42ºC以上的温度下死亡的效应。其特点在于非刺激性。但是，确定癌变部位和测量癌变温度的问题还没有解决。认为癌细胞具有不同于普通细胞的介电常数和电导率。因此，通过测量这些常数，就有可能知道癌症的温度。这是本研究的主要目的。1989年，我们利用50 ω特性阻抗的同轴型涂布器进行了测量实验材料反射系数的基础实验，得到了材料的介电常数和电导率。材料。我们也明确了在这个实验中存在的实际问题。1990年，我们研制了三种新型涂布器，并对其介电常数和电导率进行了较为仔细和精确的测量。我们还建立了计算机系统来自动测量这些量。在1991年和1992年，我们继续了同样的实验，然而，我们检查了介电常数和电导率在50到550 MHz的频率范围内。我们用盐水、烤火腿和人体作为实验材料。接下来，我们测量的不是反射系数S_<11>，而是透射系数S_<21>。采用扫描法测量系数S_<2l>导致阻抗CT。利用这一结果，我们还研究了介电常数和电导率对温度的依赖性，并证实了它们对温度的依赖性很大。这一结果显示了利用阻抗CT技术测量人体癌症温度的未来可能性。从1989年到1992年，我们测量了各种生物实验材料的介电常数和电导率以及它们对温度的依赖关系。我们已经获得了确定人体癌症位置和温度的基本数据。少

Usually performing operations and/or using chemical medicines are popular for remedying cancers. Recently hyperthermia methods are utilized in many cases. This method makes use of the effect that cancer cells die out for the temperature above 42 ﾟC. Its characteristics exists in non-stimulating property. However, the problems of identifying the location of the cancer and measuring the temperature of it are not solved yet. It is considered that cancer cells have different dielectric constants and conductivities from those of ordinary cells. So, by measuring these constants, it is possible to know the temperature of the cancer. These are the main purposes of this research.In 1989, we made the fundamental experiments for measuring the reflection coefficient of the experimental materials using the coaxial type applicator having 50 OMEGA characteristic impedance and obtained the dielectric constants and the conductivities of the. materials. We also made clear the practical problems in this … More experiment. In 1990, we made three kinds of new applicators and measured the dielectric constant and the conductivity more carefully and exactly. We also built up the computer system to measure these quantities automatically. In 1991 and 1992, we continued the same experiments, however, we examined the dielectric constant and the conductivity over the frequency range from 50 to 550 MHz. As the experimental materials, we had used salty water, roast ham and human body. Next, not measuring the reflection coefficient S_<11>, but we measured the transmitting coefficient S_<21>. Measuring the coefficient S_<2l> leads to the impedance CT with the scanning method. Using this result, we also examined the temperature dependency of the dielectric constant and the conductivity and confirmed their large dependency on it. This result shows the future possibility of measuring the temperature of the cancer in the human body using the technology of the impedance CT.Through 1989 to 1992, we had measured dielectric constants and conductivities of various biological experimental materials as well as the temperature dependency of them. We had obtained the basic data for identifying the location and the temperature of the cancer in the human body. Less