High Resolution Ultrasound in Interventional Radiology

我们试图创建一个实时超声成像工具，用于指导干预，其分辨率超过 使用CT获得，但不需要放射或碘化造影剂。医学的进步 成像和设备技术允许用于诊断和治疗各种疾病的微创手术， 紊乱实时超声已经成为许多图像引导介入的一个组成部分。优势 超声成像的优势包括低成本、无电离辐射和解剖结构的实时可视化， physiology.我们的方法将是：1）创建扩展孔径2D换能器（512 × 16个元件）， 以数百微米的面内分辨率成像9 cm的扩展方位场（以提供宽的 2）将2D阵列应用于对多个相邻平面成像（以便于观察 活检针或消融），3）通过使用平面波传输实现每秒30体积的更新速率 为了增强对比度成像模式并实现新颖的波束形成算法，4）集成用于 畸变校正，以及5）将该技术应用于B模式、彩色多普勒、体积矢量流成像， 对比成像该阵列将实现使用平铺模块，可以在一个模式依赖切换 以实现B型成像、彩色多普勒和对比成像。过去4年，斯坦福大学和 南加州大学设计了一种成人扩展孔径腹部成像系统， 展示了可以实现的改进的空间分辨率、视场和对比度。我们利用这些 这里的工具开发了一个高容量率监测肝脏干预的能力。我们的目标是实现这一目标 1）创建和集成可拼接的声学/电子模块，以实现信号缓冲和多路复用 并创建具有仰角聚焦的大孔径阵列。利用新设计的集成电路（IC）的 和高灵敏度和宽带宽的单晶换能器材料，我们将构建单独的2D阵列 具有共同集成的传感器和电子器件的模块。2)优化引导活检和消融的方案 在幻影和动物研究中。A）创建用于小病灶成像和微波消融的软件。我们 将实施基于奇异值分解（SVD）的波束形成以用于像差校正。B）评估 在体模和离体组织中的性能。C）评估针放置的速度和准确性。D）行为 对比成像和活体猪肝消融研究。3)进行诊断和介入成像 研究作为概念的证明。A）测试对成年志愿者的肝脏进行成像并建立信号的协议 与体模相比，B）评估肝脏脉管系统和病变的3D可视化， 转诊进行肝脏病变MR或CT成像的患者。C）将消融区的3D可视化与 在转诊接受肝脏消融术的患者中进行对比增强CT（CECT）。

We seek to create a real-time ultrasound imaging tool for guiding interventions, with resolution that exceeds that obtained using CT but without the need for radiation or iodinated contrast agents. Advancements in medical imaging and device technology allow minimally-invasive procedures for the diagnosis and treatment of various disorders. Real-time ultrasound has become an integral aspect of many image-guided interventions. Advantages of US imaging include the low cost, lack of ionizing radiation and real-time visualization of anatomy and physiology. Our approach will be to: 1) create an extended aperture 2D transducer (512 by 16 elements) capable of imaging an extended azimuthal field of 9 cm with in-plane resolution of hundreds of microns (to provide a wide field of view at high resolution), 2) apply the 2D array to image multiple adjacent planes (to facilitate the view of biopsy needles or ablations), 3) achieve a 30 volume per second update rate by using plane wave transmissions to enhance contrast imaging modes and implement novel beam formation algorithms, 4) integrate methods for aberration correction, and 5) apply this technology in B-Mode, color Doppler, volumetric vector flow imaging and contrast imaging. The array will be realized using tiled modules that can be switched in a mode-dependent fashion to accomplish B-Mode imaging, color Doppler and contrast imaging. Over the past 4 years, Stanford and the University of Southern California have designed an adult extended-aperture abdominal-imaging system and demonstrated the improved spatial resolution, field of view and contrast that can be achieved. We exploit these tools here to develop a high-volume rate capability for monitoring liver interventions. Our aims to accomplish this are to: 1) Create and integrate tileable acoustic/electronic modules to implement signal buffering and multiplexing and create a large aperture array with elevational focusing. Utilizing newly designed Integrated Circuits (IC)’s and highly sensitive and wide-bandwidth single crystal transducer material, we will construct individual 2D array modules with co-integrated transducers and electronics. 2) Optimize the protocols for guiding biopsy and ablation in phantom and animal studies. A) Create software for imaging of small lesions and microwave ablation. We will implement singular value decomposition (SVD) based beam formation for aberration correction. B) Evaluate performance in phantoms and ex vivo tissue. C) Assess speed and accuracy of needle placements. D) Conduct contrast imaging and ablative studies in porcine liver in vivo. 3) Conduct diagnostic and interventional imaging studies as a proof of concept. A) Test the protocols to image the liver of adult volunteers and establish the signal to noise ratio in vivo as compared with phantoms. B) Assess 3D visualization of liver vasculature and lesions in patients referred for MR or CT imaging of a liver lesion. C) Compare the 3D visualization of ablated zones to contrast-enhanced CT (CECT) in patients that are referred for liver ablation.