Active Detector Dual Energy Chest Radiography CAD

描述（由申请人提供）：我们提出的研究的具体目的是开发一种改进的计算机辅助检测和表征（CAD）系统，用于胸部x线图像中的肺结节。总体目标是提高胸部x线摄影的性能，使其在保持低剂量、易于使用和低成本的同时，提供一种可行的肺癌筛查方法。根据最近的一篇论文，“今天，肺癌的诊断通常是基于疾病晚期的症状，或者是出于各种与肺癌检测无关的目的而进行的胸部x光检查。”不幸的是，在美国，没有任何社会或政府机构建议进行筛查，即使是高风险患者，如气流阻塞的吸烟者或职业接触者，包括石棉。”我们的方法在两个方面提供了重要的技术创新。首先，与之前几乎所有的工作不同，我们将使用双能量图像。这为CAD提供了传统x线片无法获得的数据，具有显著的优势。它可以用于计算不同组成的人体结构的独立图像。例如，一张图像只包含软组织结构，而另一张图像只显示含有高原子序数材料（如钙）的结构。软组织图像消除了肋骨阴影，这是胸片CAD误差的主要来源。高原子序数组织图像可用于计算结节是否含有钙的敏感指标，这是良性与恶性诊断的重要因素。常规x光片也可用，因此其数据可以与双能量数据相结合，以提高整体准确性。第二个创新是使用了一种新型的双能量探测器，我们称之为“主动探测器”。这种有源探测器采用一种新的电光方法来提供比以前的双能探测器平均能量差大得多的数据。因此，临床质量的图像可以用目前最先进的剂量的四分之一。在第一阶段，我们将开发和实施一个有源探测器双能CAD系统的第一版。我们将用安装在加州大学戴维斯医学中心的原型机制作的现有图像来展示它的可行性。

DESCRIPTION (provided by applicant): The specific aim of our proposed research is to develop an improved, computer-assisted detection and characterization (CAD) system for lung nodules in chest x-ray images. The overall objective is to improve the performance of chest radiography so it will provide a viable lung cancer screening method while retaining its low dose, ease of use and low cost. According to a recent paper, "Today, lung cancer is most often diagnosed on the basis of symptoms of advanced disease or when chest x-rays are taken for a variety of purposes unrelated to lung cancer detection. Unfortunately, in the United States no society or governmental agency recommends screening, even for patients with high risks, such as smokers with airflow obstruction or people with occupational exposures, including asbestos." Our approach provides significant technological innovation in two respects. First, unlike almost all previous work, we will use dual energy images. These provide data, unavailable from conventional radiographs, with significant advantages for CAD. It can be used to compute separate images of body structures with different composition. For example, one image contains only soft-tissue structures while another displays only structures containing high atomic number materials, such as calcium. The soft tissue image eliminates rib shadows, which are a principal source of errors in chest radiography CAD. The high atomic number tissue image can be used to compute a sensitive indicator of whether a nodule contains calcium, an important factor in a benign vs. malignant diagnosis. The conventional radiograph is also available so its data can be combined with the dual energy data to improve overall accuracy. A second innovation is the use of a new type of dual energy detector, which we call an "active detector." The active detector uses a new electro-optical approach to provide data with a much larger difference in average energy than previous dual energy detectors. As a result, clinical quality images can be made with one-fourth the dose of the current state-of-the-art. In Phase I, we will develop and implement a first version of an active detector dual energy CAD system. We will show its feasibility with existing images made with our prototype installed at the University of California, Davis Medical Center.