Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany.
J Acoust Soc Am. 2012 Feb;131(2):1121-30. doi: 10.1121/1.3675003.
The pressure fields of two different high intensity focused ultrasound (HIFU) transducers operated in burst mode were measured at acoustical power levels of 25 and 50 W (continuous wave equivalent) with three different hydrophones: A fiber-optic displacement sensor, a commercial HIFU needle hydrophone, and a prototype of a membrane hydrophone with a protective coating against cavitation effects. Additionally, the fields were modeled using a freely available simulations software package. The measured waveforms, the peak pressure profiles, as well as the spatial-peak temporal-average intensities from the different devices and from the modeling are compared and possible reasons for differences are discussed. The results clearly show that reliable pressure measurements in HIFU fields remain a difficult task concerning both the reliability of the measured values and the robustness of the sensors used: Only the fiber-optic hydrophone survived all four exposure regimes and the measured spatial-peak temporal-average intensities varied by a factor of up to 1.5 between the measurements and the modeling and between the measurements among themselves.
两种不同高强度聚焦超声（HIFU）换能器在爆裂模式下的压力场在 25 和 50 W 声功率水平下（连续波等效）进行了测量，使用了三种不同的水听器：光纤位移传感器、商用 HIFU 针状水听器和具有抗空化效应保护涂层的膜片水听器原型。此外，还使用了一个免费提供的模拟软件包对声场进行了建模。对不同设备和建模得到的测量波形、峰值压力分布以及空间峰值时间平均强度进行了比较，并讨论了产生差异的可能原因。结果清楚地表明，在 HIFU 场中进行可靠的压力测量仍然是一项艰巨的任务，这涉及到测量值的可靠性和所使用传感器的稳健性：只有光纤水听器在所有四种暴露条件下都能幸存下来，并且测量的空间峰值时间平均强度在测量值与建模值之间以及测量值之间变化了高达 1.5 倍。
