Spiral Spectroscopic Human Neuroimaging

描述（由申请人提供）：磁共振光谱成像技术的广泛使用受到几个挑战的阻碍，包括低信噪比（SNR），主场和射频激励场的不均匀性，成像时间和体积覆盖的繁琐限制，以及从耦合或重叠光谱分量中检测和分离信号的能力有限。我们通过开发高场强（3T和7T）的光谱采集和处理方法来解决这些限制，提供更高的信噪比，增加的化学位移色散和简化的耦合模式；ii)螺旋读出梯度，通过提供两个数量级的编码加速来解决MRSI的空间编码限制；iii)并行射频传输，以减轻高场下射频激励的严重不均匀性；iv)接收线圈阵列以提高信噪比并实现并行编码。一些有吸引力的光谱成像应用为这项工作提供了强大的动力，包括体积，高空间分辨率光谱成像，大大减少扫描时间以提高患者耐受性，以及结合多维方法来检测细微不同的化学位移物种。

DESCRIPTION (provided by applicant): Widespread use of magnetic resonance spectroscopic imaging techniques is hindered by several challenges, including low signal-to-noise ratio (SNR), inhomogeneity of the main field and RF excitation field, cumbersome constraints on imaging time and volumetric coverage, and limited ability to detect and separate signals from coupled or overlapping spectral components. We address these limitations by developing spectroscopic acquisition and processing methods for i) high field strength (3T and 7T), providing higher SNR, increased chemical shift dispersion and simplified coupling patterns; ii) spiral readout gradients that address the spatial encoding limitations in MRSI by offering two orders of magnitude of encoding acceleration; iii) parallel RF transmission to mitigate the severe non-uniformity of RF excitation at high field; and iv) receive coil arrays to improve SNR and enable parallel encoding. Several attractive spectroscopic imaging applications provide a strong motivation for this work, including volumetric, high spatial resolution spectroscopic imaging, greatly reduced scan times for improved patient tolerance, and the incorporation of multidimensional methods to detect subtly different chemical shift species.