Fully Compensated Dynamic Shim System for In Vivo MRI and MRS

用于体内 MRI 和 MRS 的完全补偿动态匀场系统

• 批准号: 7395060
• 负责人: ROBIN A DE GRAAF
• 金额: $ 18.39万
• 依托单位: RESONANCE RESEARCH, INC.
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7395060
• 关键词: Affect; Air; Amplifiers; Animal Experimentation; Animals; Bone Tissue; Brain; Clinical; Computer software; Custom; Data; Data Quality; Dependence; Development; Diagnosis; Diffusion Magnetic Resonance Imaging; Disease; Echo-Planar Imaging; Ensure; Equipment; Facility Construction Funding Category; Financial compensation; Functional Magnetic Resonance Imaging; Future; Goals; Human; Image; Imagery; Injury; Institution; Label; Magnetic Resonance; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Magnetism; Methods; Morphologic artifacts; Numbers; Operative Surgical Procedures; Organ; Phase; Physics; Physiologic pulse; Predisposition; Process; Pulse taking; Research; Residual state; Resolution; Sampling; Signal Transduction; Slice; Small Business Technology Transfer Research; Standards of Weights and Measures; Structure; System; Techniques; Testing; Time; Tissues; Travel; Universities; Update; Work; analog; base; clinical application; commercialization; design; experience; improved; in vivo; magnetic field; novel strategies; prototype; soft tissue; spectroscopic imaging; tool

DESCRIPTION (provided by applicant): Functional MRI, diffusion MRI and MR spectroscopy and spectroscopic imaging have great potential for the study and diagnosis of disease and injury, and guiding surgical therapy. All of these methods benefit greatly from the added sensitivity, resolution and contrast from high field strength magnets (3T and above). However, the advantages of higher magnetic fields have not been fully realized due to the increasingly confounding effects of magnetic field inhomogeneity (MFI) caused by magnetic susceptibility differences between air and tissue. MFI leads to signal loss and spatial distortion in MRI and loss in spectral resolution and sensitivity in MRS. The loss of reliability due to these artifacts is a major reason why these techniques have not seen wide use in clinical applications. Current methods of magnetic field homogenization (i.e. shimming) work well on small volumes but are inadequate over larger objects, like the entire human brain. Over the last five years, the MR group at Yale University has developed the technique of dynamic shim updating (DSU) which allows greatly improved magnetic field homogeneity over extended regions. Dynamic shim updating divides a global 3D problem into a number of slices over which adequate magnetic field homogeneity can be achieved. Dynamically updating the pre-determined slice shims in sync with the multi-slice MRI sequence ensures optimal homogeneity for all slices. Given the maturity of the technique, as well as the increasing demand for improved magnetic field homogeneity, it is the goal of this Phase I STTR proposal to develop DSU into a commercially viable method. As all of the previous developments were performed on Yale-specific equipment, the first step towards commercialization is the development, construction and testing of a stand-alone DSU unit. Once the feasibility of the stand- alone DSU unit has been established, the road towards commercialization will be traveled in a future Phase II STTR application. Since MFI affects many facets of in vivo NMR, the successful implementation of DSU will have major impacts on almost all aspects of MRI and MRS and can thus be labeled as highly significant.

描述（由申请人提供）：功能性MRI，扩散MRI和MR光谱和光谱成像具有巨大的研究和诊断疾病和损伤的潜力，以及指导手术治疗。所有这些方法都从高磁场强度磁铁（3T及以上）的增加的灵敏度，分辨率和对比度中受益匪浅。然而，由于磁场不均匀性（MFI）的越来越混杂的影响，由于空气和组织之间的磁敏感性差异，较高的磁场的优势尚未完全实现。 MFI导致MRI的信号丢失和空间失真，以及MRS中光谱分辨率和灵敏度的损失。由于这些技术而导致的可靠性丧失是这些技术在临床应用中没有广泛使用的主要原因。当前的磁场均匀化方法（即圆形）在少量体积上很好地工作，但在较大的物体上（如整个人类大脑）不足。在过去的五年中，耶鲁大学的MR组开发了动态垫片更新技术（DSU），该技术允许在扩展区域大大改善磁场均匀性。动态垫片更新将全局3D问题划分为许多切片，在这些切片上可以实现足够的磁场同质性。动态更新预定的切片垫片与多片MRI序列同步可确保所有切片的最佳同质性。鉴于该技术的成熟度以及对改善磁场均匀性的需求不断增长，因此该阶段I STTR提案的目标是将DSU开发为商业上可行的方法。由于以前的所有发展都是在耶鲁大学特定设备上进行的，因此商业化的第一步是独立DSU单元的开发，构建和测试。一旦建立了独立DSU单位的可行性，商业化的道路将在未来的II阶段STTR应用中走向。由于MFI影响了体内NMR的许多方面，因此DSU的成功实施将对MRI和MRS的几乎所有方面产生重大影响，因此可以将其标记为非常重要。