AN INNOVATIVE ULTRASOUND-BASED PROSPECTIVE-GATING TECHNIQUE FOR CARDIAC COMPUTED

描述（由申请人提供）：此K-23提案描述了一个多学科，跨领域的职业发展计划，这将使主要研究者，心胸和腹部放射科医生和电气工程师成为心血管成像的生产力独立翻译研究员。 拟议研究的目的是合并计算机断层扫描（CT）和实时超声（US）的独特功能，以提供门控信号，从而获得冠状动脉的无运动CT图像。PI假设US提供与心电图（ECG）相似的实时数据，可以直接评价心脏机械运动，并且在确定心动周期内的相对心脏运动不能方面比ECG更可靠。冠状动脉疾病是一个重要的国家医疗保健问题，冠状动脉疾病的评估目前基于（1）导管冠状动脉血管造影术（CCA），其非常昂贵且具有已知的严重并发症的侵入性，或（2）CT冠状动脉血管造影术（CTCA），其目前的形式是辐射密集型或由于运动伪影而不可靠。在目标1中，PI将评价US门控相对于ECG门控在确定相对心脏静止方面的作用。在目标2中，PI将评价US导出的门控参数相对于ECG门控在通过回顾性门控CT扫描生成无运动CTCA方面的有效性。对于目标3，PI将启动基于数字信号处理和现场可编程门阵列技术的原型硬件的设计和仿真，为CTCA提供最佳的、有前景的实时触发。构建硬件的基本原理是，心脏CT前瞻性触发的严格时间分辨率要求要求必须对大量数据进行实时US分析;这无法通过软件实时完成。提出的基于机械信号的门控方法是CTCA的范式转变，并可能导致用于评估冠状动脉的经济、低辐射、快速、无创和可靠的技术。这一发展最重要的意义将是减少诊断性、侵入性CCA的数量，这些CCA揭示了“正常”动脉及其相关并发症，从而大大节省了医疗成本。更广泛地说，这种基于美国的门控技术的潜在影响是，它可以直接应用于其他诊断问题，包括呼吸门控的正电子发射断层扫描-CT和放射治疗。 拟议的K23奖学金利用PI的工程和医学相结合的背景，以及由世界知名科学家和医生科学家组成的精心挑选的多元化导师/咨询委员会。职业发展计划有三个主要组成部分：技术部分，翻译部分和临床部分。技术部分涉及开发基于硬件的触发技术，该技术将在生物医学成像领域的一位领先科学家和一位具有广泛学术和工业经验的工程教授的指导下进行。图像/信号处理和硬件设计方面的其他重点教学指导将从格鲁吉亚理工学院的电气和计算机工程以及生物医学工程系获得。翻译部分包括一个教学部分，由埃默里大学的临床研究硕士课程和北美放射学会提供的成像临床试验研讨会提供。最后，临床研究部分，包括收集和分析US，ECG和CT数据将在埃默里大学放射学和心脏病学系的国际公认的心血管成像先驱的指导下进行。该计划将在医学成像，心脏病学和生物医学工程前沿的环境中进行，具有广泛的临床，教育和研究资源。 公共卫生相关性：尽管导管冠状动脉造影术是目前评价冠状动脉的金标准，但它具有高度侵入性，并具有重大的相关医疗并发症和不可接受的高“正常”诊断结果率。为了克服该过程的风险并降低相关的高成本，可以使用真实的超声作为门控信号，以大幅减少心脏计算机断层扫描中的运动伪影。这将导致一种可靠、快速、低辐射剂量、非侵入性的替代技术来评估冠状动脉，并可能每年减少数十亿美元的医疗保健费用。

DESCRIPTION (provided by applicant): This K-23 proposal describes a multidisciplinary, cross-cutting career development program, which will enable the Principal Investigator, a Cardiothoracic and Abdominal Radiologist, and an Electrical Engineer, to become a productive independent translational researcher in cardiovascular imaging. The objective of the proposed research is to merge the unique capabilities of computed tomography (CT) and real-time ultrasound (US) to provide a gating signal in order to obtain motion-free CT images of coronary arteries. The PI hypothesizes that US, which provides real-time data similar to electrocardiography (ECG), can directly evaluate cardiac mechanical motion and would be more reliable than ECG at determining relative cardiac akinesia within a cardiac cycle. Coronary artery disease is a significant national healthcare issue, and the evaluation of coronary artery disease is currently based on either (1) catheter coronary angiography (CCA), which is very expensive and invasive with known significant complications or (2) CT coronary angiography (CTCA), which, in its current forms, is either radiation-intensive or unreliable due to motion artifacts. In Aim 1, the PI will evaluate US-gating relative to ECG-gating in determining relative cardiac quiescence. In Aim 2, the PI will evaluate the efficacy of US-derived gating parameters relative to ECG-gating in generating motion-free CTCA from retrospectively-gated CT scans. For Aim 3, the PI will initiate the design and simulation of prototype hardware based on Digital Signal Processing and Field Programmable Gate Array technologies to provide an optimal, prospective real-time trigger for CTCA. The rationale for building hardware is that the stringent temporal resolution requirements for prospective triggering of cardiac CT dictate that the US analysis be performed in real-time on a large volume of data; this cannot be accomplished by software in real-time. The proposed method of gating based on mechanical signals is a paradigm-shift for CTCA and could result in an economical, low-radiation, rapid, non-invasive and reliable technique for evaluating coronary arteries. The most important implication of this development will be a reduction in the number of diagnostic, invasive CCAs that reveal "normal" arteries, and their associated complications, resulting in dramatic healthcare cost savings. More broadly, the potential impact of this US-based gating technique is that it can be applied directly to other diagnostic problems including respiratory gating for positron-emission tomography-CT and radiation therapy. The proposed K23 scholarship takes advantage of the PI's background combining engineering and medicine and the carefully selected, diverse mentorship/advisory committee which is comprised of world- renowned scientists, and physician-scientists. The career development program has three major components: a technical component, a translational component and a clinical component. The technical component involves the development of a hardware-based triggering technique which will be performed under the mentorship of a leading scientist in biomedical imaging and an engineering professor with extensive academic and industrial experience. Additional focused didactic instruction in image/signal processing and hardware design will be obtained from the Electrical and Computer Engineering and the Biomedical Engineering Departments of the Georgia Institute of Technology. The translational component involves a didactic component, provided by Emory University's Master of Science in Clinical Research program and an Imaging Clinical Trials workshop offered by the Radiological Society of North America. Finally, a clinical research component that involves gathering and analyzing US, ECG and CT data will be performed under the mentorship of internationally recognized pioneers in cardiovascular imaging from the Departments of Radiology and Cardiology at Emory University. The program would take place in an environment which is at the cutting edge of medical imaging, cardiology, and biomedical engineering, with extensive clinical, educational and research resources. PUBLIC HEALTH RELEVANCE: Catheter coronary angiography, while the current gold standard for evaluation of coronary arteries, is nonetheless highly invasive and has major associated medical complications and an unacceptably high rate of 'normal' diagnostic findings. To overcome this procedure's risks and to reduce the associated high costs, real- time ultrasound could be used as a gating signal to drastically reduce motion artifacts in cardiac computerized tomography. This will lead to a reliable, rapid, low-radiation dose, non-invasive alternative technique for evaluating coronary arteries, and potentially decrease health care costs by several billion dollars annually.