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: 8220721
• 负责人: Piotr M Starewicz
• 金额: $ 36.37万
• 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 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8220721
• 关键词: Accounting; Affect; Air; Amplifiers; Animal Experimentation; Animals; Bone Tissue; Brain; Calibration; Clinical; Communities; Computer software; Data; Data Quality; Databases; Dependence; Development; Diagnostic Errors; Diffusion; Diffusion Magnetic Resonance Imaging; Disease; Echo-Planar Imaging; Ensure; Environment; Financial compensation; Functional Magnetic Resonance Imaging; Grant; Health; Human; Image; Imagery; Injury; Institution; Knowledge; Label; Magnetic Resonance; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Magnetism; Metabolic; Methods; Modification; Morphologic artifacts; Operative Surgical Procedures; Organ; Performance; Phase; Physics; Positioning Attribute; Predisposition; Process; Protocols documentation; Reporting; Research; Residual state; Resolution; Sampling; Signal Transduction; Slice; Small Business Technology Transfer Research; Spectrum Analysis; System; Techniques; Technology; Time; Tissues; Universities; Update; Variant; Vendor; Work; base; clinical application; commercialization; cost effective; design; disease diagnosis; flexibility; human tissue; imaging modality; improved; in vivo; interest; magnetic field; magnetic resonance spectroscopic imaging; method development; new technology; next generation; novel strategies; operation; prototype; quality assurance; soft tissue; software development; 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 decade, 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. DSU 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. Following a successful completion of the Phase I STTR grant, the current Phase II application continues the work towards commercialization of DSU. Specifically, DSU hardware will be further improved and combined with professional software to automatically set up the unit. Since DSU is significantly more complicated than regular shimming, additional software will be provided for the every day operation of the unit by standard MR users. Since MFI affects almost all facets of in vivo NMR, the successful commercialization of DSU will have major impacts on the clinical application of MRI and MRS and can thus be labeled as highly significant. PUBLIC HEALTH RELEVANCE: Magnetic resonance imaging (MRI) and spectroscopy (MRS) are the leading techniques to obtain high-quality images and metabolic profiles of intact human tissues in health and disease. Unfortunately, spatial variations in magnetic field strength introduced by the sample can severely degrade the quality of MRI and MRS data, such that distinction of normal from diseased tissues may be compromised. Current technology is not able to completely cancel the spatial magnetic field variations. The current project focuses on the development of novel technology that can significantly reduce spatial magnetic field variations, thus leading to greatly increased MRI and MRS data quality.

描述（申请人提供）：功能性MRI、扩散MRI、磁共振波谱和波谱成像在疾病和损伤的研究和诊断以及指导手术治疗方面具有巨大的潜力。所有这些方法都极大地受益于高场强磁体（3T 及以上）增加的灵敏度、分辨率和对比度。然而，由于空气和组织之间的磁化率差异引起的磁场不均匀性（MFI）的混杂效应日益增加，较高磁场的优势尚未完全实现。 MFI 会导致 MRI 中的信号丢失和空间失真以及 MRS 中的光谱分辨率和灵敏度损失。由于这些伪影而导致的可靠性损失是这些技术尚未在临床应用中广泛使用的主要原因。目前的磁场均匀化（即匀场）方法在小体积上效果很好，但对于较大的物体（例如整个人脑）来说就不够了。在过去的十年中，耶鲁大学的 MR 小组开发了动态匀场更新 (DSU) 技术，该技术可以大大改善扩展区域的磁场均匀性。 DSU 将全局 3D 问题划分为多个切片，在这些切片上可以实现足够的磁场均匀性。与多切片 MRI 序列同步动态更新预定切片垫片，确保所有切片的最佳均匀性。在成功完成第一阶段 STTR 拨款后，当前的第二阶段申请继续致力于 DSU 的商业化。具体来说，DSU硬件将进一步完善，并结合专业软件来自动设置单元。由于 DSU 比常规匀场复杂得多，因此标准 MR 用户将为设备的日常操作提供额外的软件。由于MFI几乎影响体内NMR的所有方面，DSU的成功商业化将对MRI和MRS的临床应用产生重大影响，因此可以说是非常重要的。公共健康相关性：磁共振成像 (MRI) 和光谱学 (MRS) 是获取健康和疾病状态下完整人体组织的高质量图像和代谢特征的领先技术。不幸的是，样本引入的磁场强度的空间变化会严重降低 MRI 和 MRS 数据的质量，从而可能会影响正常组织与患病组织的区分。目前的技术还无法完全消除空间磁场的变化。当前项目的重点是开发能够显着减少空间磁场变化的新技术，从而大大提高 MRI 和 MRS 数据质量。