QB-Mode Ultrasonic Imaging

描述(由申请人提供)： 提出了一种从脉冲回波超声成像系统中分离波束形成数据的线性和非线性分量的系统。该方案研究了一种基于二阶Volterra滤波(SVF)模型的分离回波数据的线性和二次分量的系统。这种分解的二次分量可以以类似于熟悉的B型成像的方式以灰度表示。这导致了一种新形式的灰度成像，在本提案中称为QB模式成像。由于非线性传播和/或微气泡超声造影剂(UCA)，QB模式图像对二次信号分量很敏感。初步结果表明，QB模式图像在空间分辨率和对比度分辨率上均优于二次谐波图像。此外，与脉冲反转(PI)等更专业的UCA成像方法的比较表明，QB模式成像能够在不需要多个发射脉冲的情况下实现对UCA的相同水平的灵敏度和特异度，从而保持超声成像系统的帧速率。这对于左心室混浊(LVO)的UCA成像是非常有利的。此外，QB模式成像增加了动态范围，允许在同一图像上显示组织和对比成分，从而在使用或不使用UCA的放射检查中进行更好的诊断。该提案要求提供资金，以进一步研究各种成像目标的QB模式成像特性(例如，使用或不使用UCA检测乳腺癌的高频探头、使用UCA的相控阵探头等)。特别是，我们将研究特定成像场景下SVF核系数的推导的优化、SVF的高效自适应实现以及在本地QB模式下和在UCA存在的情况下SVF的二次分量的脉冲压缩特性。在整个项目期间，将强调使用现场可编程阵列(FPGA)技术实时实现最优和自适应SVF。

DESCRIPTION (provided by applicant): A system for separating linear and nonlinear components of beamformed data from pulse-echo ultrasound imaging systems is proposed. This proposal investigates a system for separating linear and quadratic components of the echo data based on a second-order Volterra filter (SVF) model. The quadratic component of this decomposition can be presented in grayscale in a manner similar to the familiar B-mode imaging. This leads to a new form of grayscale imaging, referred to in this proposal as QB-mode imaging. QB-mode images are shown to be sensitive to quadratic signal components due to nonlinear propagation and/or microbubble ultrasound contrast agents (UCA). preliminary results clearly show that QB-mode images are superior to second harmonic (SH) images in both spatial and contrast resolution. Moreover, comparison with more specialized UCA imaging methods such as pulse inversion (PI) shows that QB-mode imaging is capable of achieving the same level of sensitivity and specificity to UCA without the need for multiple transmit pulses, thus preserving the frame rate of ultrasound imaging systems. This can be quite advantageous for imaging UCA for left ventricle opacification (LVO). In addition, QB-mode imaging has increased dynamic range allowing for display of tissue and contrast components on the same image allowing better diagnosis in radiologic examinations with or without UCA. This proposal requests funding to further investigate the characteristics of QB-mode imaging for a variety of imaging targets (e.g. high-frequency probes for breast cancer detection with or without UCA, phased array probes with UCA, etc.) In particular, we will investigate the optimization of the derivation of the SVF kernel coefficients for specific imaging scenarios, efficient adaptive implementation of the SVF, and pulsecompression properties of the quadratic component of the SVF in native QB-mode and in the presence of UCA. The real-time implementation of the optimal and adaptive SVFs using field programmable array (FPGA) technology will be emphasized throughout the project period.