非线性造影超声成像数值仿真方法  

Numerical simulation method of nonlinear contrast-enhanced ultrasound imaging

作　　者：程双毅 郁钧瑾 付亚鹏 他得安 许凯亮[1,2,3] Cheng Shuang-Yi;Yu Jun-Jin;Fu Ya-Peng;Ta De-An;Xu Kai-Liang(Center for Biomedical Engineering,School of Information Science and Technology,Fudan University,Shanghai 200438,China;State Key Laboratory of Integrated Chips and Systems,Fudan University,Shanghai 201203,China;Yiwu Research Institute,Fudan University,Yiwu 322000,China)

机构地区：[1]复旦大学信息科学与工程学院,生物医学工程中心,上海200438 [2]复旦大学,集成芯片与系统全国重点实验室,上海201203 [3]复旦大学义乌研究院,义乌322000

出　　处：《物理学报》2023年第15期117-126,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12274093,11974081);上海市青年科技启明星计划(批准号:20QC1400200)资助的课题.

摘　　要：近年来,基于微泡非线性的造影超声技术得到了长足发展.对比传统线性超声成像,非线性造影超声在克服杂波滤除挑战的同时,能进一步提高成像分辨率.仿真可为超声成像新机制和技术研究提供有效工具,是计算声学长期关注重点.目前广泛采用的声场仿真工具主要基于有限元法、解析法、k空间伪谱法和时域有限差分法等实现.有关组织非线性参数仿真已有较为成熟的解决方案.然而,因未考虑微泡非线性特点,仍不适于微泡非线性造影超声仿真分析.本文从微泡非线性出发,结合经典k空间伪谱法求解组织的超声回波,进而基于修正Rayleigh-Plesset方程数值计算微泡处的受迫振荡响应,提出了一种非线性造影超声成像仿真方法.随后,结合平面波成像方法,分别仿真了单个微泡和成簇微泡的B超图像,并结合不同对比多脉冲序列成像策略(脉冲反转、幅度调制、幅相调制和阵元交替)和不同平面波发射角度验证了方法有效性.相关技术有助于基于微泡非线性的造影超声技术发展.Contrast-enhanced ultrasound imaging(CEUS)based on the acoustic nonlinearity of ultrasonic microbubble has received great attention in recent years.Compared with conventional linear ultrasound imaging,nonlinear CEUS can further improve the imaging resolution while overcoming the challenge of clutter filtering.Simulation,acting as an effective tool for research on new mechanisms and technologies of ultrasound imaging,has been a long-term focus of computational acoustics.In the community of biomedical ultrasound,common sound field simulation tools are mainly based on finite element method(FEM),analytical method,kspace pseudospectral method and finite-difference time-domain method(FDTD),which are relatively mature solutions for simulating the nonlinear characteristics of tissue.However,it is still not trivial to simulate nonlinear CEUS by using the prevailing methods,as the nonlinearity of microbubble is often not considered.In this paper,we propose a simulation method of nonlinear CEUS imaging that successfully combines the microbubble nonlinearity and classic k-space pseudospectral method.Specifically,forced oscillation response of the microbubble is computed based on the modified Rayleigh-Plesset equation and such a nonlinear response is further dealt as an additional source for analyzing the nonlinear component propagation and CEUS imaging.To investigate the performance of the proposed method,B-mode images of single microbubble and clustered microbubbles are simulated based on plane wave imaging.The plane wave based CEUS imaging can thus be carried out with different compounding angles and different contrast pulse sequencing(CPS)strategies(pulse inversion,amplitude modulation,pulse inversion&amplitude modulation,and probe element alternation).Different soft-tissue and mechanical parameters of the microbubble can be adjusted by using the proposed nonlinear simulation strategy,thus providing efficient solution for CEUS simulation.Such a method can evaluate the performances of different CPS strategies,and further c

关 键 词：非线性超声仿真 超声微泡 非线性超声成像 Rayleigh-Plesset 方程 

分 类 号：TH77[机械工程—仪器科学与技术]