Simulations of the thermo-acoustic lens effect during focused ultrasound surgery
Simulations of the thermo-acoustic lens effect during focused ultrasound surgery
复制标题
DOI：
10.1121/1.1360239
复制
发表时间：
2001-05-01
影响因子：
2.4
通讯作者：
Hynynen, K
中科院分区：
文献类型：
--
作者：
Hallaj, IM;Cleveland, RO;Hynynen, K
软组织特性的实验室测量显示背景传播特性对温度的依赖性。对于典型的聚焦超声手术（FUS）应用，当计算FUS超声处理的结果时，仅需要考虑组织背景参数的缓慢变化。缓慢变化的声速的累积效应在文献中被称为热透镜或热声透镜，因为其波束失真特性。一种算法来解决耦合的声-热问题，数值结果来说明动态声速剖面的分层组织进行FUS的影响。在有和没有脂肪层的肝脏中的模拟结果表明，热声相互作用导致FUS中的动力学比简单模型预测的更复杂。从模拟预测的损伤的大小和位置都受到热声透镜效应的影响。然而，发现在1 MHz左右的高功率下来自尖锐聚焦的单元件源（F-编号从0.8到1.3）的短声处理的总体效果很小，类似于临床设置中使用的那些。(C)2001年，美国声学学会。
Laboratory measurements of soft tissue properties show a dependence of background propagation properties on temperature. For typical focused ultrasound surgery (FUS) applications, only the slow variations in tissue background parameters need to be accounted for when computing the outcome of a FUS sonication, The cumulative effect of slowly varying sound speed has been referred to in the literature as a thermal lens, or a thermo-acoustic lens because of its beam-distorting properties. An algorithm to solve the coupled acoustic-thermal problem is described, and numerical results are presented to illustrate the effects of dynamic sound-speed profiles in layered tissues undergoing FUS. The results of simulations in liver with and without a fat layer indicate that the thermal-acoustic interaction results in more complex dynamics in FUS than a simple model will predict. Both the size and the position of the lesions predicted from the simulations are affected by the thermo-acoustic lens effect. However, the overall effect from short sonications at high power from sharply focused single element sources (F-no. from 0.8 to 1,3) around 1 MHz similar to those used in clinical setups is found to be small. (C) 2001 Acoustical Society of America.