HIGHER SPEED, FIELD & SPATIAL RESOLUTION BRAIN 3D 1H MRS

描述(由申请人提供)：用质子磁共振波谱(‘H-MRS)观察到的代谢水平的变化经常用于增强高灵敏度(但不是特异性)的核磁共振。在1.5特斯拉，到目前为止，MRS已经将MRI的解剖学与癌症、癫痫、阿尔茨海默病、多发性硬化症、艾滋病毒感染、中风和其他中枢神经系统(CNS)疾病的潜在代谢联系起来。因此，预计高磁场(Bo)1.5T成像仪将为H-MRS提供亟需的灵敏度提升。不幸的是，这并没有发生：将最有用的二维和三维(3D)的H-MRS技术转换为高BOS一直受到以下因素的阻碍：较高的射频(BI)功率要求；较短的TZ降低了信噪比(SNR)增益；化学位移配准错误；以及缺乏软件来填补、设计3D定位、评估和显示大型3D MRS数据集。 这一竞争延续的长期目标是开发和实施30‘H-MRS方法，以解决上述问题，并在较高的BG下表现得更好。它们将是过去两个周期开发的混合技术的延伸。具体目标1将利用较短的T2来实现：(A)通过在感兴趣的体积上最佳地交错“板材”来实现3D覆盖，每个板材足够薄以在强梯度下与可用的B1激发，以最大限度地减少配准误差；以及(B)将空间分辨率提高到(1~m)~体素，并将覆盖范围一直扩展到头骨。特殊目标2将把3D定位引入我们的无回声、非定位、全头的H-MRS，以提供快速、成像器侧、低分辨率的“代谢定位器”。具体目标3将利用增加的灵敏度在有限的区域产生非常高的空间分辨率，(0.5-0.375米)~体素，例如视神经或脊髓，这两个区域目前都无法接触到。最后，特殊目标4将开发新的方法来检测和可视化不同代谢物的空间分布之间的关系，以简化3D‘H MRS产生的惊人的、往往令人困惑的信息量。 该项目与健康相关的是，它将提高的空间分辨率、体积覆盖范围和更短的采集时间3D‘H-MRS方法扩展到高23T磁场，以支持正在进行的和未来与多焦点和弥漫性疾病相关的中枢神经系统代谢的研究。

DESCRIPTION (provided by applicant): Changes in metabolic levels observed with proton-magnetic-resonance-spectroscopy ('H-MRS) are frequently used to augment the highly sensitive (but not specific) MRI. At 1.5 Tesla, MRS has so far linked anatomy from MRI with the underlying metabolism in cancer, epilepsy, Alzheimer's disease, multiple sclerosis, HIV infection, stroke and other disorders of the central nervous system (CNS). Therefore, it was anticipated that high-magnetic-field (Bo ) 1.5 T) imagers would provide 'H-MRS a much needed boost in sensitivity. Unfortunately, that has not happened: Translating the most useful 2 and 3 dimensional (3D) 'H-MRS techniques to high-Bos has been stymied by high radio-frequency (BI) power requirements; short TZ reducing the signal-to-noise-ratio (SNR) gain; chemical shift misregistration errors; and scarcity of software to shim, design 3D localization, evaluate and display the large 3D MRS data sets. The long term goal of this competing continuation is to develop and implement 30 'H-MRS methods to address the above issues and perform better at higher BG. They will be extensions of the hybrid techniques developed in the past two cycles. Specific Aim 1 will exploit the shorter T2s for: (a) 3D coverage by optimal interleaving of "slabs," across the volume-of-interest, each thin enough to excite with the available B1 under strong gradients to minimize the misregistration error; and (b) increase the spatial resolution to ((1 ~m )~voxels, and extend coverage all the way to the skull. Specific Aim 2 will introduce 3D localization into our non-echo, non-localized, whole head 'H-MRS, to provide a rapid, imager-side, lower-resolution "metabolic localizer." Specific Aim 3 will utilize the increased sensitivity to produce very high spatial resolution, (0.5 - 0.375 ~m )~ voxels, in restricted regions, e.g., the optic nerve or spinal cord, both of which are currently inaccessible. Finally, Specific Aim 4 will develop novel methods to detect and visualize relationships between different metabolites' spatial distributions to simplify the staggering, often confusing, amount of information generated by 3D 'H MRS. The health relatedness of this project is its extension of increased spatial resolution, volume covered and shorter acquisition time 3D 'H-MRS methods to high, 23 T, magnetic fields, to support ongoing and future studies of CNS metabolism associated with multifocal and diffuse diseases.