MR-Compatible X-Ray Tube

MR 兼容 X 射线管

• 批准号: 7466671
• 负责人: Rebecca Fahrig
• 金额: $ 26.35万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7466671
• 关键词: Abdomen; Acceleration; Address; Air; Angiography; Anodes; Area; Arteriovenous malformation; Arts; Back; Brain; Cardiac; Catheters; Clinical; Compatible; Condition; Congenital arteriovenous malformation; Devices; Electron Beam; Elements; Facility Construction Funding Category; Familiarity; Feedback; Film; Fluoroscopy; Frequencies; Goals; Hand; Heart; Heating; Hybrids; Image; Immune; Individual; Inguinal region; Intervention; Invasive; Length; Location; Magnetic Resonance Imaging; Malignant neoplasm of liver; Measurement; Modality; Modeling; Monitor; Motion; Motor; Operative Surgical Procedures; Output; Patients; Performance; Perfusion; Physiology; Placement; Pliability; Positioning Attribute; Preparation; Procedures; Process; Property; Range; Research; Research Design; Resolution; Roentgen Rays; Sclerotherapy; Solutions; Source; Speed; Spottings; Stem cells; Stroke; Structure; System; Systems Integration; Technology; Temperature; Testing; Time; Transistors; Translations; Travel; Tube; Vacuum; Vagina; Work; base; design; detector; digital; electric field; electron optics; experience; falls; foot; fundamental research; innovation; interest; magnetic field; next generation; programs; prototype; research and development; size; soft tissue

DESCRIPTION (provided by applicant): We propose to research and design an MR compatible rotating anode x-ray tube that can function immediately adjacent to a high field, 1.5T closed bore (CB) magnet, in order to maximize flexibility of X-ray/MR hybrid system design. Such an x-ray tube, integrated with other already proven components such as digital flat panel and high-frequency generator, would enable MRI information to be accessible during x-ray image-guided critical interventional procedures such as cardiac stem cell delivery, stroke treatment and liver cancer management. With a short travel distance limited only by the length of the magnet, the proposed design would minimize patient travel. This will allow the best utilization of the high resolution, high contrast and real-time imaging capabilities of angiography to be combined with excellent physiology assessment (flow, perfusion, soft tissue motion) and 3D soft tissue imaging of MRI, so that changes during a procedure can be assessed. Previously we successfully demonstrated the clinical use of a static anode x-ray system placed in the bore of a 0.5T GE Signa-SP open magnet (SP-XMR) for guiding a range of challenging procedures including creation of neo-vagina, and sclerotherapy for arteriovenous malformations. For many of the ~50 patient cases, intervention under x-ray alone had not been successful or was considered too risky; conversely, the clinicians could not have carried out the intervention under MR guidance alone. Presence of the closely integrated system enabled a minimally invasive approach. However, the SP-XMR system has modest x-ray output and a specialized magnet design which restrict wide clinical acceptance. On the other hand, operating a rotating anode x-ray tube adjacent to a high-field magnet produces significant challenges. We therefore propose innovative research to develop x-ray tube sub-components including new, MR compatible motors, and electron optics, with appropriate feedback mechanisms, so as to create a truly MR-compatible rotating-anode x-ray tube. This x-ray tube could be placed adjacent to the shortest bore magnets currently available (e.g. Siemens Espree, 4 ft. in length) allowing a translation between fields-of-view of x-ray and MR of as little as three feet. This table translation is seen often in the x-ray fluoroscopy suite when, for example, guiding catheters from the groin into the neurovasculature. Initial research and design of the new x-ray tube will include finite element modeling of both electron beam and motor components, modeling of heat distribution properties, and then using FE models as a guide, construction and testing of the components within known fields. The most efficient and MR compatible components will then be combined into an x-ray tube, and testing of the tube will be carried out to verify that tube output, focal spot distribution and lifetime are equivalent to current state-of-the-art x-ray tubes used in the fluoroscopy suite for the range of MR fields of interest. This x-ray tube will enable the next generation of hybrid XMR systems.

描述（由申请人提供）：我们建议研究和设计一种 MR 兼容旋转阳极 X 射线管，它可以紧邻高场、1.5T 闭孔 (CB) 磁体工作，以最大限度地提高 X 射线/MR 混合系统设计的灵活性。这种 X 射线管与其他已经经过验证的组件（如数字平板和高频发生器）集成，将使 MRI 信息能够在 X 射线图像引导的关键介入手术（如心脏干细胞输送、中风治疗和肝癌管理）期间获取 MRI 信息。由于移动距离短，仅受磁铁长度的限制，所提出的设计将最大限度地减少患者的移动。这将能够最好地利用血管造影的高分辨率、高对比度和实时成像功能，与出色的生理学评估（血流、灌注、软组织运动）和 MRI 的 3D 软组织成像相结合，从而可以评估手术过程中的变化。此前，我们成功演示了放置在 0.5T GE Signa-SP 开放磁体 (SP-XMR) 孔中的静态阳极 X 射线系统的临床应用，用于指导一系列具有挑战性的手术，包括创建新阴道和动静脉畸形的硬化疗法。对于约 50 例患者中的许多病例，仅通过 X 射线进行干预并不成功或被认为风险太大；相反，临床医生无法仅在 MR 指导下进行干预。紧密集成的系统的存在使得微创方法成为可能。然而，SP-XMR 系统的 X 射线输出有限，并且采用专门的磁体设计，限制了临床的广泛接受。另一方面，在高场磁体附近操作旋转阳极 X 射线管会产生重大挑战。因此，我们建议进行创新研究，开发 X 射线管子组件，包括新型 MR 兼容电机和电子光学器件，并具有适当的反馈机制，从而创建真正的 MR 兼容旋转阳极 X 射线管。该 X 射线管可以放置在当前可用的最短孔径磁铁（例如，Siemens Espree，长 4 英尺）附近，从而允许 X 射线和 MR 视场之间的转换小至三英尺。这种工作台平移经常出现在 X 射线透视套件中，例如将导管从腹股沟引导到神经血管系统时。新型 X 射线管的初步研究和设计将包括电子束和电机部件的有限元建模、热分布特性建模，然后使用 FE 模型作为指导，在已知领域内构建和测试部件。然后，最高效且与 MR 兼容的组件将被组合成 X 射线管，并对管进行测试，以验证管输出、焦斑分布和寿命与当前在感兴趣的 MR 领域范围的透视套件中使用的最先进的 X 射线管相当。该 X 射线管将使下一代混合 XMR 系统成为可能。