CORE PROJECT I: SPECTROSCOPIC METHODS

核心项目 I：光谱方法

• 批准号: 6283129
• 负责人: JAN A DEN HOLLANDER
• 金额: $ 8.36万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 1999-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6283129
• 关键词: biomedical equipment development; biomedical resource; carbohydrates; magnetic resonance imaging; nervous system; nuclear magnetic resonance spectroscopy; technology /technique

1H MRSI allows one to obtain metabolic maps of different brain compounds such as N-acetyl aspartate, creatine, choline compounds, lactate, and glutamine. By the implementation of improved acquisition techniques it has been possible to further improve the spatial resolution of these metabolite maps. By using a broad-band water/fat suppressing refocusing pulse in the measuring sequence the SNR (signal-to-noise ratio) has been improved. The use of a shorter recycle delay TR allows one to collect larger data sets, for a improved spatial resolution. With this approach it has been possible to obtain 1H MRSI data sets with a spatial resolution of 0.175 cc. This improved spatial resolution is especially important for the examination of stroke patients, and of temporal lobe epilepsy. Further improvements of the 1H MRSI technique are underway, in particular multislice capabilities to cover a larger part of the brain.  The high-contrast T1 weighted 1H MR images obtained at 4.1T allows one to segment the images in gray and white matter. This information has been used to determine the gray/white matter contribution to individual voxels of 1H MRSI measurements, and this information has been used to obtain separate measurements of metabolite ratios and concentrations of gray and white matter, This image segmentation approach has been applied to 31P data sets, to obtain measurements of PCr/ATP, and PCr/Pi for gray and white matter as well The TCA cycle activity can be measured in the human brain, by monitoring the appearance to the 13C label in the brain glutamate pool, following infusion with [1-13C]-glucose. These measurements have been extended, as to obtain separate measurements of the TCA cycling rate of gray and of white matter. Homonuclear editing techniques have been further improved, to uncover hidden resonances in the 1H MRS spectrum of the human brain, in particular to observe GABA, and glutamate. Contributions from macro molecules to the GABA resonance has been reduced, by the use of an improved editing pulse. These techniques are being used to follow GABA levels in epilepsy patients, who are on anti-seizure medication.

1H MRSI允许获得不同大脑的代谢图 化合物如N-乙酰天冬氨酸、肌酸、胆碱化合物， 乳酸盐和谷氨酰胺。 通过实施改进的收购 技术，可以进一步提高空间 这些代谢物图谱的分辨率。 通过使用宽带水/脂肪 抑制测量序列中的重聚焦脉冲， （信噪比）得到了改善。 使用较短的 再循环延迟TR允许收集更大的数据集， 提高空间分辨率。 通过这种方法， 以获得空间分辨率为0.175 cc的1H MRSI数据集。 这种改进的空间分辨率对于 检查中风患者和颞叶癫痫。 1H MRSI技术的进一步改进正在进行中， 特定的多切片能力，以覆盖更大部分的 个脑袋  4.1T高对比度1H MR T1加权像 允许将图像分割为灰色和白色物质。 这 信息已被用于确定灰/白色物质 对1H MRSI测量的个体素的贡献，以及 信息已被用来获得单独的测量， 灰色和白色物质的代谢物比例和浓度， 图像分割方法已被应用到31 P数据集， 获得灰质和白色物质的PCr/ATP和PCr/Pi测量值 以及 TCA循环活性可以在人脑中测量，通过 监测大脑谷氨酸中13 C标记的出现 合并液，输注[1- 13 C]-葡萄糖后。 这些测量 已经扩展，以获得TCA的单独测量 灰色和白色物质的循环速率。 主页编辑技术得到了进一步改进， 揭示人脑1H MRS频谱中隐藏的共振， 特别是观察GABA和谷氨酸。 的捐款 大分子的GABA共振已减少，通过使用 改进的编辑脉冲。 这些技术被用来跟踪 服用抗癫痫药物的癫痫患者的GABA水平。