聚焦超声换能器电阻抗谱实时在线监测系统  

Real-Time Online Monitoring System for Electric Impedance Spectra of Focused Ultrasound Transducers

作　　者：肖建 黄文军 刘雅璐 罗曼[1,3] 王杰 宋丹 XIAO Jian;HUANG Wenjun;LIU Yalu;LUO Man;WANG Jie;SONG Dan(State Key Laboratory of Ultrasound in Medicine and Engineering,College of Biomedical Engineering,Chongqing Medical University,Chongqing 400016,China;Key Laboratory of Biomedical Engineering,Chongqing Medical University,Chongqing 400016,China;National Engineering Research Center of Ultrasonic Medicine,Chongqing 401121,China)

机构地区：[1]重庆医科大学生物医学工程学院、超声医学工程国家重点实验室,重庆400016 [2]重庆医科大学重庆市生物医学工程学重点实验室,重庆400016 [3]超声医疗国家工程研究中心,重庆401121

出　　处：《压电与声光》2024年第3期420-428,共9页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金委员会青年基金(12204079);重庆市自然科学基金面上项目(CSTB2023NSCQ-MSX0532)。

摘　　要：高强度聚焦超声(HIFU)换能器作为聚焦超声消融手术(FUAS)系统的核心部件,其电阻抗谱是确定FUAS系统工作参数的重要参考依据,故对其进行实时在线监测具有重要意义。该文采用脉冲响应时域测量方法,将探测脉冲信号与HIFU换能器的工作时序相融合,并基于LabVIEW平台构建了一套HIFU换能器电阻抗谱实时在线监测系统,实现了对HIFU换能器电阻抗幅值与相位的高重复性及准确性的实时测量。通过对长时工作在大功率、高占空比条件下HIFU换能器电阻抗谱的实时在线监测,表明该监测系统可准确反应HIFU换能器的特征频率漂移、阻抗幅值和相位的非线性变化。这为HIFU换能器电阻抗谱实时在线监测及驱动参数优化调节提供了技术方案,对HIFU换能器的设计优化和能量损耗机制研究具有重要的应用价值。High-intensity focused ultrasound(HIFU)transducers are a core component of focused ultrasound ablation surgery(FUAS)systems,whose electric impedance spectrum is an important index to determine working parameters that significantly affect FUAS systems performance.Real-time online monitoring of this spectrum is significantly beneficial.In this study,based on pulse response time-domain measurement,by merging the detected pulse signal serial into the FUAS operational electric driving signal sequence of the HIFU transducer,a real-time online monitoring system for the electric impedance spectrum of the HIFU transducer was constructed on the Lab-VIEW platform.Highly reproducible accurate measurements towards the magnitude and phase spectrum of the HIFU transducer electric impedance were achieved.Subsequently,a monitoring system was applied to determine dynamic changes in the electric impedance of the HIFU transducer under extreme working conditions.These include long-time service,high electrical driving power and duty cycle.The results demonstrate that the proposed system accurately monitors the HIFU transducer eigen frequencies drift,alongside nonlinear changes in impedance magnitude and phase.This paper presents a technical solution for real-time online monitoring of HIFU transducer impedance during FUAS,and provides feedback for drive parameter adjustment,which has practical application value for HIFU transducer design optimization and energy loss mechanisms.

关 键 词：高强度聚焦超声(HIFU)换能器 电阻抗谱 脉冲响应 实时在线监测 

分 类 号：TN384[电子电信—物理电子学] TB552[理学—物理]