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 与常规检查相比，双能计算机断层扫描 (DECT) 可提供更多信息 CT。它越来越多地用于各种临床任务，包括组织分化、金属伪影减少、 自动去骨、对比增强和碘定量。尽管多项技术已 为 DECT 开发的一个主要限制是设备成本显着增加，这阻碍了 临床应用更加广泛。 该项目的目标是开发一种新的 X 射线源技术，以降低成本并提高 DECT 的表演。具体来说，我们提出了一种双能 X 射线源，它发出两种不同的辐射： 与通过光谱过滤或快速光谱获得的能量谱相比，能量分离增加 单独采用kVp切换方法。这将通过利用两个阴极-阳极对和一个电压来实现 在施加恒定的管电压时，分压器可降低其中一个阳极的有效电压。辐射 来自两个阳极的光进一步优化，通过合并两个个性化的光来减少光谱重叠 光谱滤光片。对于 DECT，通过选择性地激活阳极，X 射线辐射从两个阳极交替发射。 相应的阴极。碳纳米管 (CNT) 场发射阴极用于实现快速开关 以及以微秒精度对两束光束进行强度调制。 与现有技术相比，所提出的源的优点是：1）显着减少 设备成本 – 无需快速 kVp 切换、能量敏感探测器或两套源/探测器； 2） 增加能量分离并减少重叠，从而增强 DECT 性能； 3） 独立控制两束X射线的曝光，最大限度地减少图像噪声； 4) 启用DE-CBCT 机架旋转一次即可成像； 5）微秒级能谱瞬时切换 响应时间提高了剂量分布的准确性和可靠性。 该可行性研究将重点关注用于双能锥形束 CT (DE-CBCT) 的固定阳极 X 射线源 颌面部和头部成像，所开发的技术可应用于医学成像的其他领域 目前使用 CBCT 的领域包括图像引导放射治疗、介入放射学和四肢 成像。该方法还可以扩展到多能量（3 个或更多）以实现高级光谱成像。它可以 用于发射具有 2 个或更多能谱的光子的空间分布式 X 射线源阵列 固定龙门双能断层合成和CT。具体目标是： 1) 证明双轨制的可行性 用于低成本 DE-CBCT 的能量 X 射线源； 2) 使用原型双系统演示 DE-CBCT 成像 能量X射线源。