Phase Contrast Computed Tomography Scanner

相衬计算机断层扫描仪

• 批准号: 7229895
• 负责人: EDWIN F DONNELLY
• 金额: $ 16.96万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-27 至 2008-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7229895
• 关键词: Affect; Algorithms; Animals; Arts; Characteristics; Clinical; Custom; Data; Development; Devices; Diagnostic radiologic examination; Dose; Electrons; Human; Image; Imaging Device; Imaging Techniques; Laboratories; Laboratory Research; Lasers; Lesion; Lethal Dose 50; Light; Low Dose Radiation; Malignant Neoplasms; Measurement; Medical; Metabolism; Modality; Mus; Neurologic; Output; Phase; Production; Radiation; Radiology Specialty; Research Personnel; Resolution; Rodent Model; Role; Scanning; Science; Side; Soft Tissue Neoplasms; Source; Synchrotrons; System; Techniques; Time; Tissues; Tomography, Computed, Scanners; Tube; Universities; Work; X-Ray Computed Tomography; absorption; central coherence; concept; design; improved; programs; reconstruction; soft tissue; tumor; tumor growth

DESCRIPTION (provided by applicant): While computed tomography (CT) imaging is by far the most predominant anatomical imaging device used to evaluate non-neurological malignancies in humans, its role in imaging small animal malignancies (especially rodent models of human tumors) has been much more limited due to the unacceptably high radiation dose levels necessary to image at the needed spatial resolution. These doses can interfere with tumor growth and metabolism and thus may compromise the actual scientific studies the scans were intended to evaluate. The development of phase-contrast imaging, however, offers one potential mechanism for improving soft tissue tumor detectability in small animals with potentially lower radiation doses. Phase-contrast imaging utilizes the diffraction of x-rays as they pass through tissue interfaces to obtain additional information not available to traditional absorption radiography. In addition, these images have a characteristic edge-enhancement effect that tends to increase lesion conspicuity. Because the technique depends upon the diffraction, rather than absorption, of x-rays, these images can be obtained at radiation doses potentially much lower than conventional absorption radiographs. Our laboratory has been investigating phase-contrast radiography (PC-R) for several years, and recently we have partnered with the x-ray source development group of the Free Electron Laser (PEL) Laboratory (located on the Vanderbilt University Campus) to investigate the feasibility of incorporating a newly- developed high-intensity x-ray production device into our existing PC-R system. The x-ray source is completely independent of the Free Electron Laser itself and has been designed specifically to function as a "table-top" source that could be generally available to medical facilities. The x-ray beam produced by this source is largely monochromatic and has an extremely high spatial coherence (the central requirement of phase-contrast imaging). In addition, it has been designed to provide a high x-ray flux. We now propose to extend that work into the development of a phase-contrast computed tomography scanner (PC-CT). In this study, we will optimize the imaging parameters and CT reconstruction algorithms for PC-CT and we will determine whether a small-animal PC-CT scanner is feasible by comparing PC-CT to a commercial, state-of- the-art small-animal microCT scanner using quantifiable data from images of a custom phantom and radiation dose measurements.

描述（由申请人提供）：虽然计算机断层扫描（CT）成像是迄今为止用于评价人类非神经系统恶性肿瘤的最主要解剖成像器械，但由于在所需空间分辨率下成像所需的不可接受的高辐射剂量水平，其在小动物恶性肿瘤（尤其是人类肿瘤的啮齿动物模型）成像中的作用受到了更多限制。这些剂量会干扰肿瘤的生长和代谢，因此可能会损害扫描旨在评估的实际科学研究。然而，相衬成像的发展提供了一种潜在的机制，用于提高小动物软组织肿瘤的可检测性，具有潜在的较低辐射剂量。 相衬成像利用X射线穿过组织界面时的衍射来获得传统吸收射线照相术无法获得的附加信息。此外，这些图像具有特征性的边缘增强效应，其倾向于增加病变的显著性。由于该技术依赖于X射线的衍射而不是吸收，因此可以在比传统吸收射线照片低得多的辐射剂量下获得这些图像。 我们的实验室多年来一直在研究相衬射线照相术（PC-R），最近我们与自由电子激光（PEL）实验室（位于范德比尔特大学校园）的X射线源开发组合作，研究将新开发的高强度X射线产生设备纳入我们现有的PC-R系统的可行性。X射线源完全独立于自由电子激光器本身，并且专门设计为用作医疗设施通常可用的“桌面”源。由该源产生的X射线束在很大程度上是单色的，并且具有极高的空间相干性（相衬成像的核心要求）。此外，它还被设计为提供高X射线通量。我们现在建议将这项工作扩展到相位对比计算机断层扫描仪（PC-CT）的开发中。在本研究中，我们将优化PC-CT的成像参数和CT重建算法，并将使用来自自定义体模图像和辐射剂量测量的可量化数据，通过将PC-CT与最先进的商业小动物microCT扫描仪进行比较，确定小动物PC-CT扫描仪是否可行。