Surowiec A, Shrivastava P N, Astrahan M, Petrovich Z
Department of Radiation Oncology, University of Southern California, Los Angeles 90033.
Int J Hyperthermia. 1992 Nov-Dec;8(6):795-807. doi: 10.3109/02656739209005027.
A muscle-stimulating material made of polyacrylamide gel (PAG) for testing various kinds of hyperthermia applicators was investigated. The permittivity and conductivity dispersion of PAG, as well as an internal wavelength and penetration depth, were in good agreement with those of actual muscle at frequencies between 500 MHz and 3 GHz. A single formula for PAG covering three ISM bands, most commonly used for hyperthermia, 433, 915 and 2450 MHz, is presented. The physical properties of the PAG phantom allow any desired form or shape to be moulded, including shapes conforming to the actual geometry of an interstitial or intracavitary applicator. Utilization of a multilayer phantom makes possible the generation of experimental three-dimensional specific absorption rate (SAR) distributions composed from several two-dimensional SAR images at different depths or radial distances from the applicator. Spatial resolution of 1 mm can be achieved. The two-dimensional SAR distributions at different depth values for commercial superficial applicator, an interstitial antenna and a new oesophageal applicator are presented.
研究了一种由聚丙烯酰胺凝胶（PAG）制成的用于测试各种热疗施加器的肌肉刺激材料。在500 MHz至3 GHz的频率范围内，PAG的介电常数和电导率色散以及内部波长和穿透深度与实际肌肉的情况高度吻合。给出了一个适用于三个ISM频段（热疗最常用的433、915和2450 MHz）的PAG单一公式。PAG体模的物理特性允许塑造任何所需的形式或形状，包括符合组织间或腔内施加器实际几何形状的形状。使用多层体模可以生成由在不同深度或距施加器的径向距离处的几个二维SAR图像组成的实验性三维比吸收率（SAR）分布。可以实现1毫米的空间分辨率。给出了商业浅表施加器、组织间天线和新型食管施加器在不同深度值下的二维SAR分布。
