Brain H2D MRS: Implemation and Initial Applications

Brain H2D MRS：实施和初步应用

• 批准号: 6595130
• 负责人: ZHIYUE J WANG
• 金额: $ 17.87万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6595130
• 关键词: adult human (21+); bioimaging /biomedical imaging; brain disorders; brain imaging /visualization /scanning; brain metabolism; branched chain aminoacid; child (0-11); diet therapy; electron spin resonance spectroscopy; galactosemias; gamma aminobutyrate; human subject; ketoacid; magnetic resonance imaging; maple syrup urine disease; metabolism disorder; noninvasive diagnosis; patient oriented research; sugar alcohols; technology /technique development

DESCRIPTION (provided by applicant) The long-term objective is to apply 2D 1H magnetic resonance spectroscopy (MRS) techniques in studies of pediatric neurological disorders. 1H MRS is valuable for evaluating neurological brain diseases. However, there are limitations in current clinical 1H MRS examinations. Most peaks are crowded in a narrow aliphatic spectral window, and numerous low concentration metabolites are overshadowed by a few metabolites present in higher levels, and much valuable information is lost. Most metabolites have coupled spins, and 2D MRS separates the peaks in a second frequency dimension, greatly increasing the information content of the data. Application of 2D MRS in clinical examinations will enhance the abilities for diagnoses and patient management, and improve the understanding of disease processes. The specific aims are: (1) to implement 2D spin-echo double-quantum MRS pulse sequences for in vivo measurement of brain metabolites in 1.5T clinical scanners: (1a) to implement a localized pulse sequence optimized for GABA measurement; (1b) to implement localized pulse sequences for general detection of metabolites; (1c) to implement whole-brain measurement pulse sequences for general detection of metabolites. (2) to assign and evaluate peaks detected in the normal brain: (2a) to acquire spectra from metabolite solutions; (2b) to acquire brain spectra and baselines due to macromolecules in a group of adult normal volunteers; (2c) to assign the in vivo peaks and measure metabolite levels, and to determine optimal pulse sequences for studies of Aim 3; (2d) to acquire age-matched control spectra from normal children. (3) to explore the utility of the 2D MRS techniques in patients between the ages of 7 and 11 years: (3a) to study the effects of the ketogenic diet (KD) on brain GABA levels in seizure patients; (3b) to measure the brain?s level of branched chain amino-acids (BCAA) and keto-acids (BCKA) in maple syrup urine disease (MSUD); (3c) to test the hypothesis that low levels of brain galactitol are present even under a lactose restrictive diet; (3d) to study unassigned, unusual spectral peaks found in routine clinical MRS examinations. A localized 1D double-quantum filtered MRS pulse sequence will be modified into several 2D double quantum MRS pulses for localized and whole brain measurement. Different pulse parameters will be used for different types of spin systems. A frequency selective coherent transfer pulse will be used for optimal detection of GABA, and a broadband coherent transfer pulse will be used for all other 2D pulse sequences. The measurement procedures will be applied to normal subjects first. MRS measured GABA level before and after initiation of KD therapy will be compared in seizure patients and correlated with response. The MRS measurement of BCAAs and BCKAs will be conducted during metabolic crisis and in normal conditions in MSUD and correlated with clinical condition and serum BCAA and urine BCKA. In galactosemia, 2D MRS will be used to look for low levels of galactitol, and the MRS results will be correlated with the urine galactitol levels. 2D MRS will also be used to characterize unusual peaks found in clinical practice.

描述(由申请人提供) 长期目标是应用2D 1H磁共振波谱(MRS) 儿科神经性疾病研究中的技术。1H-MRS很有价值 用于评估神经性脑部疾病。但是，存在以下限制 目前的临床核磁共振波谱检查。大多数山峰都挤在一个狭窄的 脂肪族光谱窗口，以及大量低浓度代谢物 被存在于更高水平的少数代谢物所掩盖，而且非常有价值 信息丢失。大多数代谢物都有偶联自旋，2D MRS分离 第二个频率维度的峰值，极大地增加了信息 数据的内容。2D MRS在临床检查中的应用将 增强诊断和患者管理能力，改善 对疾病过程的理解。具体目标是：(1)实施2D 用于活体脑测量的自旋回波双量子磁共振脉冲序列 1.5T临床扫描仪中的代谢物：(1)实现局部脉搏 针对GABA测量进行优化的序列；(1b)实现局部脉冲 用于一般代谢物检测的序列；(1)实施全脑 用于代谢物一般检测的测量脉冲序列。(2)转让 并评估在正常大脑中检测到的峰值：(2A)从 代谢物溶液；(2)获取脑部光谱和基线，原因是 一组成年正常志愿者的大分子；(2c)分配In 体内峰值和测量代谢物水平，并确定最佳脉搏 用于研究目标3的序列；(2d)以获得年龄匹配的对照光谱 从正常的孩子那里。(3)探讨二维磁共振波谱技术在 7至11岁的患者：(3A)研究 生酮饮食(KD)对癫痫患者大脑GABA水平的影响；(3)测量 脑组织中支链氨基酸和酮酸的S水平 枫糖浆尿病(MSUD)；(3c)检验低水平假设 即使在限制乳糖饮食的情况下，也存在大脑半乳糖醇；(3D)到 在常规临床磁共振波谱中发现的未指定的、不寻常的谱峰研究 考试。局域一维双量子滤波MRS脉冲序列将被 用于局域和整体的多个二维双量子MRS脉冲 大脑测量。不同的类型将使用不同的脉冲参数 自旋系统。频率选择性相干传输脉冲将用于 GABA的最佳检测，将使用宽带相干传输脉冲 用于所有其他2D脉冲序列。测量程序将应用于 首先是正常受试者。磁共振波谱测定启动前后的GABA水平 KD治疗将在癫痫患者中进行比较，并与疗效相关。 BCAA和BCKA的MRS测量将在代谢过程中进行 MSUD的危急和正常状态及其与临床状况的关系 血BCAA、尿BCKA。在半乳糖血症中，2D MRS将用于寻找 低水平的半乳糖醇，MRS结果将与尿液相关 半乳糖醇水平。还将使用2D MRS来表征发现的不寻常的峰 在临床实践中。