Wang Hua, Zeng Deping, Chen Ziguang, Yang Zengtao
College of Biomedical Engineering, State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and MOST, Chongqing Municipal Key Laboratory of Ultrasound Engineering in Medicine, Chongqing Medical University, Chongqing, 400016, China.
Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, United States.
Sci Rep. 2017 Apr 12;7(1):850. doi: 10.1038/s41598-017-00892-4.
Based on the acousto-optic interaction, we propose a laser deflection method for rapidly, non-invasively and quantitatively measuring the peak positive pressure of HIFU fields. In the characterization of HIFU fields, the effect of nonlinear propagation is considered. The relation between the laser deflection length and the peak positive pressure is derived. Then the laser deflection method is assessed by comparing it with the hydrophone method. The experimental results show that the peak positive pressure measured by laser deflection method is little higher than that obtained by the hydrophone, confirming that they are in reasonable agreement. Considering that the peak pressure measured by hydrophones is always underestimated, the laser deflection method is assumed to be more accurate than the hydrophone method due to the absence of the errors in hydrophone spatial-averaging measurement and the influence of waveform distortion on hydrophone corrections. Moreover, noting that the Lorentz formula still remains applicable to high-pressure environments, the laser deflection method exhibits a great potential for measuring HIFU field under high-pressure amplitude. Additionally, the laser deflection method provides a rapid way for measuring the peak positive pressure, without the scan time, which is required by the hydrophones.
基于声光相互作用，我们提出了一种用于快速、非侵入性且定量测量高强度聚焦超声（HIFU）场峰值正压的激光偏转方法。在HIFU场的表征中，考虑了非线性传播的影响。推导了激光偏转长度与峰值正压之间的关系。然后通过将激光偏转方法与水听器方法进行比较来评估该方法。实验结果表明，激光偏转方法测得的峰值正压略高于水听器测得的结果，证实两者具有合理的一致性。考虑到水听器测得的峰值压力总是被低估，由于不存在水听器空间平均测量误差以及波形失真对水听器校正的影响，激光偏转方法被认为比水听器方法更准确。此外，注意到洛伦兹公式在高压环境下仍然适用，激光偏转方法在测量高压幅值下的HIFU场方面具有很大潜力。另外，激光偏转方法提供了一种快速测量峰值正压的方法，无需水听器所需的扫描时间。
