Development of Spectral Phase Contrast Micro-CT

光谱相差显微CT的研制

• 批准号: 10153771
• 负责人: Mini Das
• 金额: $ 61.75万
• 依托单位: UNIVERSITY OF HOUSTON
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10153771
• 关键词: 3-Dimensional; Address; Algorithms; Animal Experiments; Animal Model; Animals; Area; Blood; Blood Vessels; Calibration; Clinical; Collaborations; Contrast Media; Contrast Sensitivity; Coupled; Czech Republic; Data; Detection; Development; Discrimination; Dose; Geometry; Grant; Image; Image Enhancement; Iodine; Liposomes; Longitudinal Studies; Malignant Neoplasms; Maps; Masks; Measurement; Measures; Methods; Mus; Performance; Phase; Preclinical Drug Development; Process; Property; Radiation Dose Unit; Research Personnel; Resolution; Retrieval; Roentgen Rays; Scheme; Signal Transduction; Source; Structure; System; Task Performances; Technology; Testing; Thick; Time; Tissue imaging; Tissues; Tube; Universities; Variant; Vendor; Work; absorption; animal imaging; anticancer research; attenuation; base; contrast enhanced; contrast imaging; cost; design; detector; electron density; experimental study; imaging capabilities; imaging modality; imaging study; improved; in vivo; in vivo imaging; industry partner; innovation; microCT; nanoparticle; next generation; novel; parametric imaging; phase change; photon-counting detector; prostate cancer model; public health relevance; sensor; simulation; soft tissue; tomography; transmission process; tumor

Development of Spectral X-Ray Phase-Contrast Micro-CT Project Summary A challenging aspect of in vivo micro-CT relates to the required deleterious radiation dose levels - particularly for studies required to follow the same subject longitudinally. The main constraint is the poor attenuation contrast for x-rays in soft tissue and the need for long imaging times. Researchers have studied the use of multi-energy (or spectral) x-ray acquisitions to perform material decomposition with micro-CT systems, but the versatility of these methods is again constrained by the same contrast-dose trade-off. Phase-contrast imaging (PCI) can provide significant phase-enhanced contrast at higher energies, thus potentially reducing micro-CT dose. However, existing PCI methods still require high dose and long imaging times for accurate phase retrieval. We have recently developed an algorithmic approach to spectral PCI that enables dose and imaging times commensurate with attenuation imaging. Our hypothesis is that PCI performed under normal clinical constraints can yield better tissue quantitation and small feature delineation at lower dose than attenuation imaging. We shall develop a unique spectral micro-CT system with both PCI and non-PCI capabilities to test this hypothesis. A key system component will be an innovative high-performance, high-resolution photon- counting detector (PCD) to be developed jointly under this grant by the University of Houston and Advacam s.r.o. Two non-interferometric PCI geometries will be evaluated. The first specific aim is to design the micro- CT system based on considerations such as source kVp and the PCD sensor thickness, pixel size, and energy bin configuration. PCI-specific criteria include magnification and the x-ray mask properties. Optimization studies will be carried out for both the PCI and the non-PCI modes. For Aim 2, we will work with Advacam to develop the wide-area, high frame rate and high Z sensor PCD for the system. The high-performance PCD will be constructed based on Medipix3RX ASIC technology and will feature high resolution and built-in spectral correction schemes and fast readouts. Under Aim 3, the micro-CT unit will be constructed and energy calibration and correction schemes will be developed to allow efficient system performance. Our fourth specific aim is to compare the performance of the PCI and non-PCI modes of spectral micro-CT with physical phantoms and animal studies to evaluate the enhancement of low contrast sensitivity. In vivo studies using liposomal iodine nanoparticles will examine the ability of PCI to distinguish differences in blood vascularity for treatment- responsive and treatment-resistive prostate cancer models in mice.

能谱X射线相差显微CT的研制 项目概要 体内微型 CT 的一个具有挑战性的方面涉及所需的有害辐射剂量水平 - 特别是 用于需要纵向跟踪同一主题的研究。主要限制是衰减差 软组织中 X 射线的对比度以及需要较长的成像时间。研究人员研究了使用 多能量（或光谱）X 射线采集，通过微型 CT 系统进行材料分解，但 这些方法的多功能性再次受到相同的造影剂剂量权衡的限制。相差成像 (PCI) 可以在较高能量下提供显着的相位增强对比度，从而可能减少显微 CT 剂量。然而，现有的 PCI 方法仍然需要高剂量和长成像时间才能获得准确的相位 检索。我们最近开发了一种光谱 PCI 算法方法，可实现剂量和成像 时间与衰减成像相当。我们的假设是 PCI 在正常临床情况下进行 与衰减相比，约束可以在较低剂量下产生更好的组织定量和小特征描绘 成像。我们将开发一种独特的光谱显微CT系统，具有PCI和非PCI功能来测试 这个假设。一个关键的系统组件将是创新的高性能、高分辨率光子 休斯顿大学和 Advacam 在此资助下联合开发计数检测器 (PCD) 有限公司将评估两种非干涉 PCI 几何形状。第一个具体目标是设计微型 CT 系统基于源 kVp 和 PCD 传感器厚度、像素尺寸和能量等考虑因素 仓配置。 PCI 特定标准包括放大倍率和 X 射线掩模属性。优化研究 将对 PCI 和非 PCI 模式进行。对于目标 2，我们将与 Advacam 合作开发 该系统的广域、高帧率和高 Z 传感器 PCD。高性能PCD将 基于 Medipix3RX ASIC 技术构建，具有高分辨率和内置光谱 校正方案和快速读数。根据目标 3，将建造微型 CT 装置并提供能源 将开发校准和校正方案以实现高效的系统性能。我们的第四个具体 目的是比较光谱显微 CT 的 PCI 和非 PCI 模式与物理体模的性能 和动物研究来评估低对比敏感度的增强。使用脂质体进行体内研究 碘纳米颗粒将检查 PCI 区分血管分布差异进行治疗的能力 - 小鼠的反应性和治疗抵抗性前列腺癌模型。