Large aperture and wideband modular ultrasound arrays for the diagnosis of liver cancer

我们的项目有两个基本目标：1）开发模块化大孔径，高通道数阵列， 相关的电子产品，并使这些模块广泛提供给学术界，和2）使用这些 阵列，以改善腹部超声（US）诊断肝癌，特别是难以成像 患者原发性肝癌患者的总体5年相对生存率为16%。在许多情况下， 成像用于监测由病毒感染或肝硬化引起的肝脏疾病，并检测向肝硬化的转变。 超声检查是筛查这些有癌症风险的患者的唯一推荐方法。 然而，在腹壁厚度大于2.5 cm的患者中，仅检测到33%的病变。更 超过2/3的美国人现在超重或肥胖，通道数阵列和阵列占用空间更大 将改善这一人群的成像，并改善一般情况下小病变的检测， 人口我们的方法解决了提高分辨率（大孔径和带宽），灵敏度（单 晶体换能器）、用于超分辨率成像的高帧速率（数百帧/秒是可行的）、产量（阵列 由高成品率模块组成）和图像对比度（新的切换功能实现新的波束形成 方法）。横向US分辨率与换能器孔径成反比，因此， 提高分辨率需要增加换能器元件和电子通道的数量 先进的波束形成方法。即使存在畸变组织，我们也表明， 通过扩展孔径实现的成像有助于小结构的可视化。我们建议创建PIN- PMN-PT阵列模块，尺寸为16个元素（方位角）x 32个元素（仰角），将被组合 形成大阵列。用户可选择的ASIC矩阵提供了选择的机会： 在单个模块内，联合收割机在立面上组合镜像元件，或者在立面上联合收割机组合相邻元件， 方位角或仰角。结果，大孔径阵列内的4096个元件可以同时被 从一个可编程的扫描仪。我们的具体目标跨越大面积阵列的发展 技术，该技术的集成，以创建大面积的凹面阵列，适用于腹部 成像和使用由此产生的技术来检测肝癌。初步工作已导致 原型阵列和ASIC模块的制造。加州大学戴维斯分校的团队是第一批制作 多频阵列;南加州大学开创了高频阵列，目前是家庭沃德尼基（20年 在GE的超声ASIC开发经验），并将与我们合作开发高 通道计数阵列;杜克大学率先开发了使用大孔径的策略; Verasonics是可编程超声系统的领先制造商，将与我们合作开发 并将其分发给超声界。这个独特的团队将开发这项技术， 评估其在人体研究中的用途，并将传播这项技术。

Our project has two fundamental goals: 1) develop modular large aperture, high channel count arrays with associated electronics and make these modules widely available to the academic community, and 2) use these arrays to improve abdominal ultrasound (US) for the diagnosis of liver cancer, particularly for difficult to image patients. The overall 5-year relative survival rate for patients with primary liver cancer is 16%. In many cases, imaging is used to monitor liver disease resulting from viral infections or cirrhosis and to detect a transition to malignancy, and ultrasound is the only recommended method for screening such patients at risk for cancer. Yet, in patients with an abdominal wall thickness greater than 2.5 cm, only 33% of lesions were detected. More than 2/3 of Americans are now overweight or obese and larger channel count arrays and larger array footprints will improve imaging within this population as well as improving the detection of small lesions in the general population. Our approach addresses improved resolution (large aperture and bandwidth), sensitivity (single crystal transducers), high frame rate for super-resolution imaging (hundreds of frame/sec feasible), yield (array is composed of high yield modules), and image contrast (new switching capabilities enable new beamformation methods). Lateral US resolution is inversely proportional to the transducer aperture and consequently, improved resolution requires an increased number of transducer elements and electronic channels as well as advanced beam formation methods. Even in the presence of aberrating tissues we show that the contrast achieved from an extended aperture facilitates the visualization of small structures. We propose to create PIN- PMN-PT array modules of dimension 16 elements (azimuth) by 32 elements (elevation) which will be combined to form large arrays. The user selectable ASIC matrices provide the opportunity to select: 512 elements from within a single module, to combine mirrored elements in elevation or to combine neighboring elements in azimuth or elevation. As a result, 4096 elements within the large aperture array can simultaneously be addressed from a programmable scanner. Our specific aims span the development of the large area array technology, the integration of that technology to create large area concave arrays adapted for abdominal imaging and the use of the resulting technology to detect liver cancer. Preliminary work has resulted in the fabrication of prototype array and ASIC modules. The UC Davis team has been one of the first to produce multi-frequency arrays; USC has pioneered high frequency arrays and is currently home to Wodnicki (20 years of experience in ultrasound ASIC development at GE) and will collaborate with us on the development of high channel count arrays; Duke University has pioneered the development of strategies to use large apertures; Verasonics is the leading manufacturer of programmable ultrasound systems and will work with us to develop the technology and to distribute it to the ultrasound community. This unique team will develop the technology, evaluate its use in a human study and will disseminate the technology.