A THEORETICAL-STUDY OF NONLINEAR EFFECTS WITH FOCUSED ULTRASOUND IN TISSUES - AN ACOUSTIC BRAGG PEAK
A THEORETICAL-STUDY OF NONLINEAR EFFECTS WITH FOCUSED ULTRASOUND IN TISSUES - AN ACOUSTIC BRAGG PEAK
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DOI：
10.1016/0301-5629(85)90014-6
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发表时间：
1985-01-01
影响因子：
2.9
通讯作者：
SWINDELL, W
中科院分区：
文献类型：
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作者：
SWINDELL, W
这是一项理论研究，当聚焦的超声波束在类似组织的介质中被吸收时，会产生吸收功率密度。具体的应用是选择性组织加热用于[人类]癌症热疗。结果用增强比表示，该增强比描述了当考虑非线性效应时吸收功率密度的分数增益，相对于仅考虑线性效应时产生的吸收功率密度。从换能器的（高斯）直径为0.12 m，曲率半径为0.16 m，工作频率为1 MHz的标准配置开始，进行了一次改变换能器和组织参数的数值灵敏度分析。增强比总是大于1，在光束焦点附近的区域通常在1.5-2的范围内。预测是，非线性效应将可能是有用的，有选择地增加在焦点区域的温度上升的焦点涂抹器。
This is a theoretical study of the absorbed power density that arises when a focused ultrasound beam is absorbed in a tissue-like medium. The specific application is selective tissue heating for [human] cancer hyperthermia. Results are expressed in terms of an enhancement ratio which describes the fractional gain in absorbed power density when nonlinear effects are taken into account relative to the absorbed power density that results when only linear effects are considered. Starting from a standard configuration in which the transducer has a (Gaussian) diameter of 0.12 m, a radius of curvature of 0.16 m and an operating frequency of 1 MHz a numerical sensitivity analysis is performed in which transducer and tissue parameters are varied one at a time. Enhancement ratios are invariably greater than unity, often being in the range of 1.5-2 for regions near the focus of the beam. The prediction is that nonlinear effects will probably be useful in selectively increasing the temperature rise in the focal region of a focused applicator.