Improved spectral quality for 3D MR spectroscopic imaging using a high spatial resolution acquisition strategy
Improved spectral quality for 3D MR spectroscopic imaging using a high spatial resolution acquisition strategy
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DOI：
10.1016/s0730-725x(02)00645-8
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发表时间：
2003-02-01
影响因子：
2.5
通讯作者：
Maudsley, AA
中科院分区：
文献类型：
--
作者：
Ebel, A;Maudsley, AA
在大脑的H-1磁共振波谱成像(MRSI)中，受局部磁化率变化影响的区域的光谱质量通常会显著下降，这会导致光谱线型变宽和扭曲。在这份报告中，提出了一种改进的体积回波平面光谱成像(3DEPSI)的采集策略，它扩展了可以观察到的大脑区域。以较高的空间分辨率对数据进行采样，然后对局部B-O漂移进行校正并进行重建，以使最终的空间分辨率与以常规较低空间分辨率获取的3D EPSI数据相匹配。用这两种采集方案在1.5T下获得的活体数据的比较表明，高空间分辨率的采集在许多有问题的脑区提供了相当大的谱线宽度，尽管对于本研究中使用的矩阵大小，信噪比降低了约1.4到1.6倍。然而，增加的噪声的影响在很大程度上被改善的光谱质量所抵消，导致使用自动光谱分析获得的代谢物图像质量的总体改善。(C)2003 Elsevier Science Inc.保留所有权利。
Spectral quality in H-1 MR spectroscopic imaging (MRSI) of the brain is often significantly degraded in regions subject to local magnetic susceptibility variations, which results in broadened and distorted spectral lineshapes. In this report, a modified acquisition strategy for volumetric echo-planar spectroscopic imaging (3D EPSI) is presented that extends the region of the brain that can be observed. The data are sampled at higher spatial resolution, then corrected for local B-O shifts and reconstructed such that the final spatial resolution matches that of 3D EPSI data acquired with the conventional lower spatial resolution. Comparison of in vivo data obtained at 1.5 T with these two acquisition schemes shows that the high spatial resolution acquisition provides considerable reduction of spectral linewidths in many problematic brain regions, though with a reduction in signal-to-noise ratio by a factor of approximately 1.4 to 1.6 for the matrix sizes used in this study. However, the effect of the increased noise was largely offset by the improved spectral quality, leading to an overall improvement of the metabolite image quality obtained using automated spectral analysis. (C) 2003 Elsevier Science Inc. All rights reserved.