Analyzer-based Phase Contrast Imaging System Development and Evaluation

拟议的项目涉及一种新型、低剂量的x射线设备的新设计，用于 基于分析仪的相衬成像(ABI)，这是一种使用X射线折射来 显著改善乳房和其他软组织的成像。ABI有 已经被很好地记录在同步加速器设施中产生非凡的图像，但是 紧凑型ABI原型需要比实际时间长得多的成像时间 临床实用。我们开发了一种突破性的方法，包括 一些创新的设计概念，当组合在一起时，预计将提供 在8.3秒内以100微米分辨率进行全乳房成像。建议的目标是 该项目将有条不紊地设计、优化和构建这样一个ABI系统，并 在专家读者研究中评估它的输出。ABI成像提供了许多重要的 潜在优势：1)ABI具有非常高的固有软组织图像对比度，这是由于 X射线折射和强散射抑制的物理学，承诺提供清晰的 钙化和毛刺的可视化；2)ABI可作为平面成像 方法类似于乳房X光照相，但也可用于断层合成或计算机 断层扫描(CT)模式；3)ABI无需注射造影剂；4)ABI可 减少辐射剂量，因为它可以在更高的X射线能量下工作(准 在~60keV的单色)；5)在ABI中看到的图像细节可能最终消除 需要断层合成或CT，从而减少了临床上需要阅读的图像；6)ABI 可允许区分钙化类型，从而提高特异性；以及7) ABI可以对组织密度进行定量成像。基于一个初步的原型 装置，我们已经建立了临床实用ABI可行性的强有力证据 性能。ABI系统开发是一个复杂的软硬件协同设计 进程。这个过程中的主要元素将定义项目的具体目标为 具体内容如下：1.设计并构建了一个紧凑型ABI成像系统，以演示其实用性 成像时间。2.开发仿真和体模工具。3.优化图像处理 和迭代重建方法。4.使用体外整体评价成像系统 乳房标本和杂交组织幻影。

The proposed project concerns a new design for a novel, low-dose x-ray device for analyzer-based phase contrast imaging (ABI), a modality that uses x-ray refraction to produce dramatic improvements in imaging of the breast and other soft tissues. ABI has been well documented to produce extraordinary images at synchrotron facilities, but compact ABI prototypes have required imaging times that are far longer than what is practical for clinical use. We have developed a breakthrough approach, including a number of innovative design concepts that, when combined, are expected to deliver whole-breast imaging at 100 µm resolution in 8.3 seconds. The goal of the proposed project will be to methodically design, optimize, and construct such an ABI system and evaluate its output in an expert reader study. ABI imaging offers many important potential benefits: 1) ABI has very high inherent soft-tissue image contrast due to the physics of x-ray refraction and strong scatter rejection, promising to provide clear visualization of calcifications and spiculations; 2) ABI can act as a planar-imaging method like mammography, but can also be used in tomosynthesis or computed tomography (CT) modes; 3) ABI has no need for injected contrast agent; 4) ABI may reduce radiation dose, because it can operate at higher x-ray energies (quasi- monochromatic at ~60keV); 5) the image detail seen in ABI may ultimately eliminate the need for tomosynthesis or CT, resulting in fewer images to be read in the clinic; 6) ABI may permit calcification types to be discriminated, thereby improving specificity; and 7) ABI permits quantitative imaging of tissue density. Based on a preliminary prototype device, we have established strong evidence of feasibility of clinically practical ABI performance. ABI system development is a complex hardware-software co-design process. The main elements in this process will define the project's specific aims as follows: 1. Design and construct a compact ABI imaging system to demonstrate practical imaging time. 2. Develop simulation and phantom tools. 3. Optimize image processing and iterative reconstruction methods. 4. Evaluate imaging system using ex vivo whole breast specimens and hybrid tissue phantoms.