Sherar M D, Clark H, Cooper B, Kumaradas J, Liu F F
Ontario Cancer Institute/Princess Margaret Hospital, Toronto, Ontario, Canada.
Int J Hyperthermia. 1994 Sep-Oct;10(5):723-31. doi: 10.3109/02656739409022450.
The effectiveness of hyperthermia treatments is often limited by temperature inhomogeneity that arises in the treatment field due to variable tissue properties and blood flow. Moreover, blood flow can change during a treatment, leading to the formation of hot and cool areas even if the initial temperature distribution is uniform. A variable microwave array attenuator has been constructed, that will enable the field patterns of single element microwave waveguide hyperthermia applicators to be altered during treatment, to improve temperature homogeneity. The coupling bolus was designed with an array of individually controlled elements, each filled with a microwave absorbing saline solution. Additions or withdrawals of saline are made to alter the power deposition in a specific area of the treatment field. Thermographic measurements were made in muscle equivalent phantom materials, with the bolus/waveguide assembly. Results showed that the variable array attenuator was able to significantly alter the heating pattern of a large waveguide applicator.
热疗的有效性常常受到治疗区域内温度不均匀性的限制，这种不均匀性是由组织特性和血流的变化所引起的。此外，在治疗过程中血流可能会发生变化，即使初始温度分布是均匀的，也会导致冷热区域的形成。已经构建了一种可变微波阵列衰减器，它能够在治疗过程中改变单元素微波波导热疗器的场型，以提高温度均匀性。耦合推注器设计有一系列独立控制的元件，每个元件都填充有微波吸收盐溶液。通过添加或抽取盐溶液来改变治疗区域特定部位的功率沉积。使用推注器/波导组件在肌肉等效体模材料中进行了热成像测量。结果表明，可变阵列衰减器能够显著改变大型波导治疗器的加热模式。
