Developing a dual energy x-ray source for low-cost spectral CT

开发用于低成本能谱 CT 的双能 X 射线源

• 批准号: 10430843
• 负责人: OTTO Z ZHOU
• 金额: $ 22.65万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10430843
• 关键词: Algorithms; Anodes; Area; Carbon Nanotubes; Cathodes; Characteristics; Clinical; Data Set; Development; Dose; Effectiveness; Electrodes; Equipment; Excision; Feasibility Studies; Filtration; Goals; Head; Image; Imaging Device; Imaging technology; Interventional radiology; Iodine; Limb structure; Measures; Medical Imaging; Metals; Methods; Modeling; Morphologic artifacts; Noise; Patient imaging; Performance; Photons; Production; Radiation; Reaction Time; Research; Roentgen Rays; Rotation; Scientist; Source; Spottings; Structure; System; Techniques; Technology; Tissue Differentiation; Translating; Tube; Tungsten; Vacuum; Work; X-Ray Computed Tomography; base; bone; cone-beam computed tomography; contrast enhanced; cost; design; design and construction; detector; driving force; experience; image guided radiation therapy; improved; maxillofacial; prototype; radiologist; reconstruction; simulation; spectral energy; spectrograph; tomosynthesis; virtual; voltage

ABSTRACT Dual energy computed tomography (DECT) provides significantly more information compared to a regular CT. It is increasingly used for a variety of clinical tasks including tissue differentiation, metal artifact reduction, automatic bone removal, contrast enhancement, and iodine quantification. Although several technologies have been developed for DECT, a major limitation is a significantly increased equipment cost, which has hindered the more widespread clinical use. The goal of this project is to develop a new x-ray source technology to reduce the cost and to enhance the performances of DECT. Specifically, we propose a dual energy x-ray source that emits radiations with two distinct energy spectra with an increased energy separation compared to those obtained by spectral filtration or the rapid kVp switching method alone. This will be accomplished by utilizing two cathode-anode pairs and a voltage divider to reduce the effective voltage of one of the anodes, at a constant applied tube voltage. The radiations from the two anodes are further optimized to reduce the spectral overlap by incorporating two individualized spectral filters. For DECT, x-ray radiation is emitted alternately from the two anodes by selectively activating the corresponding cathode. The carbon nanotube (CNT) field emission cathodes are used to enable rapid switching and intensity modulation of the two beams with micro-second accuracy. The advantages of the proposed source compared the current technologies are: 1) Significantly reduced equipment cost – no rapid kVp switching, energy sensitive detector or two sets of source/detector is required; 2) Increased energy separation and reduced overlap which will lead to an enhanced DECT performance; 3) Independent control of the exposures of the two x-ray beams to minimize image noise; 4) Enabling DE-CBCT imaging in one gantry rotation; and 5) Instantaneous switching of the energy spectrum with micro-second response time resulting in improved accuracy and reliable in the dose profile. This feasibility study will focus on a fixed-anode x-ray source for dual-energy cone-beam CT (DE-CBCT) for maxillofacial and head imaging, the technology developed can be applied to other areas of medical imaging where CBCT is currently deployed such as image guided radiation therapy, interventional radiology and extremity imaging. The approach can also be extended to multi-energy (3 or more) for advanced spectral imaging. It can be used for spatially distributed x-ray source array that emits photons with 2 or more energy spectra from for fixed-gantry dual energy tomosynthesis and CT. The Specific Aims are: 1) Demonstrating the feasibility of a dual energy x-ray source for low-cost DE-CBCT; and 2) Demonstrating DE-CBCT imaging using a prototype dual energy x-ray source.

抽象的 与常规 CT。它越来越多地用于各种临床任务，包括组织分化，金属伪像减少， 自动去除骨骼，对比度增强和碘定量。尽管有几种技术有 是用于DECT开发的，一个主要限制是设备成本大大增加，这阻碍了 更多宽度临床用途。 该项目的目的是开发一种新的X射线源技术来降低成本并增强成本 DECT的表演。具体而言，我们提出了一个双能X射线源，该源排放两个不同的辐射 与光谱过滤或快速获得的能量分离相比，能量分离增加了 KVP切换方法。这将通过使用两个阴极轴对和电压来实现 分隔器在恒定施加的管电压下降低其中一个阳极的有效电压。辐射 从两个阳极中进一步优化了两个阳极，以减少两种个性化的频谱重叠 光谱过滤器。对于DECT，X射线辐射是通过选择性激活的两种阳极发出的 相应的阴极。碳纳米管（CNT）田间发射阴极用于启用快速开关 并以微秒的精度对两个梁的强度调节。 比较当前技术的提议来源的优点是：1）显着降低 设备成本 - 不需要快速的KVP切换，能量敏感的检测器或两组源/检测器； 2） 增加能量分离并减少重叠，这将导致DECT性能增强； 3） 独立控制两个X射线梁的暴露，以最大程度地减少图像噪声； 4）启用DE-CBCT 在一个龙门旋转中成像； 5）用微秒瞬时切换能谱 响应时间可提高准确性，并在剂量曲线中可靠。 这项可行性研究将集中于双能锥束CT（DE-CBCT）的固定轴X射线源 颌面和头部成像，开发的技术可以应用于其他医学成像领域 目前部署了CBCT的地方，例如图像引导的放射疗法，介入放射学和肢体 成像。该方法也可以扩展到用于高级光谱成像的多能（3或更多）。它可以 用于空间分布式的X射线源阵列，该量阵列以2或更多的能量光谱从for发射照片 固定剂双能断层和CT。具体目的是：1）证明双重的可行性 低成本DE-CBCT的能量X射线源； 2）使用二型原型演示DE-CBCT成像 能量X射线源。