Optimization of In-Line Phase-Contrast Mammography

描述（由申请人提供）：相敏X射线成像（PSI）是诊断成像的一个令人兴奋的前沿，有望获得非常详细的软组织图像，同时显著降低对患者的辐射剂量。PSI背后的基本概念已经知道了很多年，但由于X射线管和数字探测器的最新技术进步，该技术现在才开始实用于临床应用。申请人将在伊利诺伊理工学院（NT）的医学成像研究中心（MIRC）接受博士后培训，该研究中心是美国领先的PSI研究小组之一。在该项目中，申请人将利用这个机会对PSI的主要类型之一进行严格的新研究，即用于乳腺X射线摄影的在线相位对比成像或相位对比乳腺X射线摄影（PCM）。具体而言，本项目的主要目标是设计，优化和构建PCM系统并评估其性能。虽然从之前的研究（以及市场上的商业产品）中可以清楚地看出，在X射线乳腺图像中可以观察到相位对比效应，但尚未进行全面的临床相关性能评价。这项研究将使用新的乳腺数据和计算机模型来模拟和建立一个优化的PCM在线系统，并评估其在患病组织中产生质量密度波动的临床有用图像的能力。该项目的具体目标如下：（1）使用多图像X射线摄影测量系统表征乳腺组织的物理X射线特性。(2)将这些测量与计算乳腺模型和PCM在线系统模拟结合使用，通过调整台式系统的物理参数来优化图像质量。(3)构建优化的台式系统并评估其临床应用能力。传统的X射线图像（基于吸收）涉及有害的辐射吸收并提供有限的灵敏度，而X射线相衬图像显示与通过组织的X射线传播速度相关的组织质量密度的细微差异。在较高的X射线能量下，这种现象占吸收对比度的1，000倍以上，例如在普通放射摄影中使用的那些，其中乳房组织吸收的电离辐射少得多。这些特性使得低剂量相衬乳腺摄影成为一种令人兴奋的可能性。 公共卫生相关性：

DESCRIPTION (provided by applicant): Phase-sensitive x-ray imaging (PSI) is an exciting frontier of diagnostic imaging, promising highly detailed images of soft tissue while dramatically reducing radiation dose to the patient. The basic concepts behind PSI have been known for many years, but the technology is only now becoming practical for clinical use due to recent technical advances in x-ray tubes and digital detectors. The applicant will receive postdoctoral training in the Medical Imaging Research Center (MIRC) at the Illinois Institute of Technology (NT), one of the leading PSI research groups in the U.S. In this project, the applicant will take advantage of this opportunity to conduct a rigorous new study of one of the main types of PSI, namely in-line phase contrast imaging for mammography, or phase-contrast mammography (PCM). Specifically, the main goal of this project is to design, optimize, and build a PCM system and evaluate its performance. While it is clear from previous studies (and a commercial product on the market) that phase contrast effects can be seen in x-ray breast images, no comprehensive clinically relevant performance evaluations have been conducted. This research will use new breast data and computer models to simulate and build an optimized PCM in-line system and assess its ability to produce clinically useful images of mass density fluctuations in diseased tissue. The proposed project has the following specific aims: (1) Characterize the physical x-ray properties of breast tissue using a multiple-image radiography measurement system. (2) Use these measurements in conjunction with computational breast models and PCM in-line system simulations to optimize image quality by adjusting the physicalparameters of a benchtop system. (3) Build the optimized benchtop system and evaluate its capabilities for clinical application. Whereas conventional x-ray images (based on absorption) involve hazardous radiation absorption and provide limited sensitivity, x-ray phase contrast images show subtle differences in tissue mass density that are linked to the x-ray propagation speed through tissue. This phenomenon dominates absorption contrast by more than 1,000 times at higher x-ray energies, such as those used in general radiography, where breast tissue absorbs far less ionizing radiation. These properties make low-dose phase-contrast mammography an exciting possibility. PUBLIC HEALTH RELEVANCE: