标题： 化学化学位移选择性绝热脉冲（CHEAP）：7T下快速高分辨率下场3D 1H-MRSI 显示英文标题

标题： CHEmical-shift selective Adiabatic Pulse (CHEAP): Fast and High Resolution Downfield 3D 1H-MRSI at 7T

摘要： 关键分子如三磷酸腺苷（ATP）、谷胱甘肽（GSH）和肌肽（hCs）——在人体大脑代谢过程中起核心作用，其检测仍然难以实现或具有挑战性，尤其是在高场强1H-MRSI中。 传统的3D 1H-MRSI在体内面临诸多挑战，包括信噪比低和水的磁化转移效应，导致测量时间延长和分辨率降低。 为解决这些限制，我们提出了一种下场强3D-MRSI方法，旨在以增强的空间分辨率和适用于7T临床实践的速度测量下场强代谢物。 将化学位移选择性绝热脉冲（CHEAP）技术整合到回波平面光谱成像（EPSI）读出序列中，用于下场强代谢物和水参考的3D-MRSI。 五名健康受试者和两名胶质瘤患者被扫描以测试可行性。 在这项工作中，CHEAP-EPSI技术被证明可以显著提高空间分辨率至0.37 ml，同时将扫描时间减少至10.5分钟。 其显著优势包括低特定吸收率、有效抑制水和脂质信号以及最小的基线失真，使其成为研究或潜在诊断用途的宝贵工具。 CHEAP-EPSI提高了下场强代谢物如N-乙酰天冬氨酸（NAA+）和DF8.18（ATP&GSH+）的检测灵敏度，并为健康和疾病大脑代谢的研究提供了新可能性。 显示英文摘要

摘要： The key molecules such as triphosphate (ATP), glutathione (GSH), and homocarnosine (hCs) - central to metabolic processes in the human brain remain elusive or challenging to detect with upfield 1H-MRSI. Traditional 3D 1H-MRSI in vivo faces challenges, including a low signal-to-noise ratio and magnetization transfer effects with water, leading to prolonged measurement times and reduced resolution. To address these limitations, we propose a downfield 3D-MRSI method aimed at measuring downfield metabolites with enhanced spatial resolution, and speed acceptable for clinical practice at 7T. The CHEmical-shift selective Adiabatic Pulse (CHEAP) technique was integrated into echo-planar spectroscopic imaging (EPSI) readout sequence for downfield metabolite and water reference 3D-MRSI. Five healthy subjects and two glioma patients were scanned to test the feasibility. In this work, CHEAP-EPSI technique is shown to significantly enhance spatial the resolution to 0.37 ml while simultaneously reducing the scan time to 10.5 minutes. Its distinct advantages include low specific absorption rate, effective suppression of water and lipid signals, and minimal baseline distortions, making it a valuable tool for research or potentially diagnostic purposes. CHEAP-EPSI improves the detection sensitivity of downfield metabolites like N-acetyl-aspartate (NAA+) and DF8.18 (ATP&GSH+), and offers new possibilities for the study of metabolism in healthy and diseased brain.