A Novel Low Dose and Accurate Phase Sensitive Breast Tomosynthesis (PBT) System based on Photon Counting Detector Technology for Cancer Imaging

一种新型低剂量高精度相位敏感乳腺断层合成摄影系统 用于肿瘤成像的光子计数探测器技术 项目摘要： 本项目将致力于建立一个临床驱动的相位敏感乳腺断层合成（PBT）成像系统 采用光子计数X射线探测器技术，降低辐射剂量，提高 相位恢复方法数字乳腺断层合成摄影（DBT）和PBT原型使用能量积分 在低剂量水平下引入相当大的电子噪声的探测器，其限制了减少总辐射的能力。 次给药结束利用多色X射线束的光谱平均，可以获得诸如 在相敏成像中不能准确地恢复组织的投影电子密度 方法严格适用于单色X射线束。可以使用能量分辨光谱仪来 抑制电子噪声并充分利用相位恢复过程。但这样的 这种方法将是耗时的，并且不能在临床世界中实现。我们提出利用光子 计数检测器技术与相敏成像技术以解决所述限制。光子 具有消除电子噪声的能力的计数检测器潜在地允许相敏成像 在降低辐射剂量水平的同时保持出色的成像质量，增强的组织对比度， 和组织类型识别能力。利用窄能量仓成像，光子计数探测器限制了 多色X射线束中各种光子能量的贡献，这将潜在地有助于 准确地检索组织的定量信息。这种用于乳腺癌成像的技术 既不可用也不优化。这些是本提案中提出的主要目标：（1）开发内联 PBT原型，采用高分辨率二维光子计数探测器。全面 表征光谱PBT;确定探测量子效率，测量空间分辨率， 评估噪声特性、计数率性能，确定能量仓的宽度和位置;（2） 优化相位恢复方法以精确量化相位图和投影电子 乳腺组织密度;（3）进行图像质量和剂量节省与现有的 利用能量积分探测器的PBT原型和DBT系统。拟议项目将进一步 促进了乳腺相位敏感成像向临床世界的转化，并提高了灵敏度 和乳腺癌检测的特异性，同时降低辐射剂量。

A Novel Low Dose and Accurate Phase Sensitive Breast Tomosynthesis (PBT) System based on Photon Counting Detector Technology for Cancer Imaging Project Summary: This project will focus to build a clinically driven phase sensitive breast tomosynthesis (PBT) imaging system using the photon counting x-ray detector technology to reduce the radiation dose and improve the accuracy of phase retrieval methods. Digital breast tomosynthesis (DBT) and PBT prototypes use the energy integrating detectors which introduce considerable electronic noise at low dose levels that limit the ability to reduce the total dose. With the spectral averaging of polychromatic x-ray beams, the quantitative information such as the projected electron densities of tissues is not accurately retrieved in phase sensitive imaging as the phase retrieval methods hold rigorously for monochromatic x-ray beams. One can employ energy resolving spectrometer to suppress the electronic noise and take the full advantage of the phase retrieval process. However, such an approach will be time-consuming and cannot be realized in the clinical world. We propose the utilization of photon counting detector technology with phase sensitive imaging technique to address the stated limitations. Photon counting detectors with their ability to eliminate the electronic noise potentially allow the phase sensitive imaging of breast at reduced radiation dose levels while preserving excellent imaging quality, enhanced tissue contrast, and tissue type identification capabilities. With narrow energy bin imaging, photon counting detectors limit the contributions of various photon energies in the polychromatic x-ray beam, and this will potentially help in accurately retrieving the quantitative information of the tissue. Such a technology for breast cancer imaging is neither available nor optimized. These are the primary aims proposed in this proposal: (1) Developing an inline PBT prototype that incorporates a high-resolution two-dimensional photon counting detector. We will fully characterize the spectral PBT; determining the detective quantum efficiency, measuring the spatial resolution, evaluating the noise properties, count rate performance, determining the width and location of energy bin; (2) Optimizing the phase retrieval methods for accurate quantification of the phase maps and projected electron densities of the breast tissues; (3) Conducting the image quality and dose saving comparisons with the existing PBT prototypes and DBT systems that utilize the energy integrating detectors. The proposed project will further facilitate the translation of the phase sensitive imaging of breast to the clinical world and enhance the sensitivity and specificity of breast cancer detection while reducing the radiation dose.