Kreider Wayne, Bailey Michael R, Ketterling Jeffrey A
Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, Washington 98105, USA.
J Acoust Soc Am. 2009 Feb;125(2):1240-5. doi: 10.1121/1.3050272.
New lithotripters with narrower foci and higher peak pressures than the original Dornier HM3 electrohydraulic lithotripter have proven to be less effective and less safe. Hence, accurate measurements of the focal characteristics of lithotripter shock waves are important. The current technique for measuring beamwidth requires a collection of single-point measurements over multiple shock waves, thereby introducing error as a result of any shock-to-shock variability. This work reports on the construction of a hydrophone array sensor and on array measurements of individual lithotripter shock waves. Beamwidths for an electrohydraulic lithotripter with a broad-focus HM3-style reflector and a narrow-focus modified reflector were measured using both new and worn electrodes as well as two different electrical charging potentials. The array measured the waveform, beamwidth, and focal location of individual shock waves. The HM3-style reflector produced repeatable focal waveforms and beam profiles at an 18 kV charging potential with new and worn electrodes. Corresponding measurements suggest a narrower beamwidth than reported previously from averaged point measurements acquired under the same conditions. In addition, a lack of consistency in the measured beam profiles at 23 kV underscores the value of measuring individual shock waves.
与最初的多尼尔HM3型液电碎石机相比，焦点更窄、峰值压力更高的新型碎石机已被证明效果更差、安全性更低。因此，准确测量碎石机冲击波的焦点特性非常重要。当前测量束宽的技术需要在多个冲击波上进行单点测量的集合，从而由于任何冲击波间的变化而引入误差。这项工作报告了一种水听器阵列传感器的构建以及对单个碎石机冲击波的阵列测量。使用新电极和磨损电极以及两种不同的充电电位，测量了具有宽焦点HM3型反射器和窄焦点改良反射器的液电碎石机的束宽。该阵列测量了单个冲击波的波形、束宽和焦点位置。HM3型反射器在18 kV充电电位下使用新电极和磨损电极时产生了可重复的焦点波形和束轮廓。相应的测量表明，束宽比之前在相同条件下通过平均点测量所报告的更窄。此外，在23 kV时测量的束轮廓缺乏一致性，这突出了测量单个冲击波的价值。
