Development of radiological clips having ultrasound identification

项目总结 放射标志物或夹子是诊断成像的重要工具，因为它们可以放置在 身体允许随着时间的推移和多次扫描识别特定的组织。用于新辅助化疗 (NAC)在乳腺癌中，成像被用来分期肿瘤大小，识别可能的淋巴结转移，以 指导肿瘤、病变和淋巴结的活检，并监测肿瘤的大小和外观 时间到了。在肿瘤的初步识别和阳性淋巴结、化疗应用和 手术，几个月就可以过去了。在NAC之前，肿瘤、病变和可疑淋巴结常被标记 使用放射学夹子，以便能够在手术前重新识别它们。这是必要的，因为 在NAC的过程中，肿瘤和淋巴结的外观可以改变，甚至正常化。 近年来，已经设计和制造了许多夹子，目的是提供更好的 使用超声等方式进行实时成像下的图像对比度和识别。超声波是 在这些应用中首选，因为它是安全的，实时的，便携的，可以在床边使用。最初它是 人们认为由金属制成的简单夹子设计将为超声波提供足够高的对比度 在B型超声中定位夹子将是简单的。然而，在实践中，识别 放射学剪辑可能很困难，因为成像领域中的多个明亮散射体在外观上可能相似 与剪辑中的信号相对应。结果，随着时间的推移，新的夹子被开发出来，具有各种形状和 尺寸、不同的表面纹理和复合材料特性。虽然制造商声称 这些夹子设计解决了在B超上可视化的问题，并允许识别不同的 组织，但这些主张在实践中尚未实现。正确的可视化问题仍然很重要。 而且这些夹子并不总是可识别的，特别是在初始夹子放置后的后续成像研究中。 因此，我们建议开发一种新型的放射学夹子，它可以提供可视化的能力 通过超声波成像，还可以识别组织中的特定夹子。新的夹子由一个小的 生物兼容超声源和检测超声成像脉冲的驱动电路。超音波 成像脉冲然后触发由几个小振荡器组成的电路，以驱动超声源 发射特定的编码超声波信号。超声波信号将提供唯一的识别码 超声不仅要清楚地显示和定位夹子的特异性，而且要识别特异性 Clip，即超声识别(USID)。{我们的剪辑可见性不取决于剪辑的回声，但 在发射和处理的唯一片断信号上。为了开发这些放射学夹子，我们提出了两个 明确的目标。第一个目标是设计、制造和测试能够提供唯一ID的USID放射夹 标签。第二个目标是展示独立版本的放射夹在组织中的能力- 模仿幻影和{在活体中}。

PROJECT SUMMARY Radiological markers or clips are an important tool for diagnostic imaging because they can be placed in the body allowing identification of specific tissues over time and over multiple scans. For neoadjuvant chemotherapy (NAC) in breast cancer, imaging is used to stage tumor size, to identify possible lymph nodes for metastases, to guide biopsy of both tumors, lesions and lymph nodes and to monitor the size and appearance of tumors over time. Between the initial identification of a tumor and positive lymph nodes, chemotherapy application and surgery, several months can pass. Before NAC, tumor, lesions and suspicious lymph nodes are often marked with radiological clips in order to be able to re-identify them before surgery. This is necessary because the appearance of the tumors and lymph nodes can change or even normalize over the course of NAC. In recent years, a multitude of clips have been designed and manufactured with the goal of providing better image contrast and identification under real-time imaging with modalities such as ultrasound. Ultrasound is preferred in these applications because it is safe, real time, portable and can be used at the bedside. Initially it was thought that simple clip designs made from metal would provide sufficiently high contrast for ultrasound that locating the clips in B-mode ultrasound would be straightforward. However, in practice, identification of radiological clips can be difficult as multiple bright scatterers in the imaging field can look in appearance similar to the signal from a clip. As a result, over time new clips have been developed that have a variety of shapes and sizes, different surface textures and compound material properties. While manufacturers have asserted that these clip designs solve the problem of visualization on ultrasound B-mode and {allow identification of different tissues}, these claims have not been realized in practice. The problem of proper visualization is still significant and these clips are not always identifiable especially on follow on imaging studies after initial clip placement. Therefore, we propose to develop a new type of radiological clip that can provide the ability to be visualized by ultrasonic imaging but also to identify the specific clip in the tissue. The new clip consists of a small biocompatible ultrasonic source and driving circuit that detects an ultrasonic imaging pulse. The ultrasonic imaging pulse then triggers the circuit, comprised of several small oscillators, to drive the ultrasonic source to emit a specific encoded ultrasonic signal. The ultrasonic signal will provide a unique identification code allowing the clip to not only be clearly visualized and localized with specificity by ultrasound, but also to identify the specific clip, i.e., ultrasound identification (USID). {Our clip visibility does not depend on the echogenicity of the clip but on the unique clip signal that is emitted and processed}. To develop these radiological clips we propose two specific aims. The first aim is to design, build and test USID radiological clips capable of providing unique ID tags. The second aim is to demonstrate the capabilities of a stand-alone version of the radiological clips in tissue- mimicking phantoms and {in vivo}.