DTI of human skeletal muscle: the effects of diffusion encoding parameters, signal-to-noise ratio and T2 on tensor indices and fiber tracts
DTI of human skeletal muscle: the effects of diffusion encoding parameters, signal-to-noise ratio and T2 on tensor indices and fiber tracts
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DOI：
10.1002/nbm.2959
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发表时间：
2013-11-01
影响因子：
2.9
通讯作者：
Strijkers, Gustav J.
中科院分区：
文献类型：
--
作者：
Froeling, Martijn;Nederveen, Aart J.;Strijkers, Gustav J.
在这项研究中，我们进行了模拟，以解决扩散编码参数，信噪比（SNR）和T-2对骨骼肌扩散张量指数和纤维束的影响。在适当的情况下，通过人体骨骼肌的体内扩散张量成像（DTI）证实和验证模拟。具体而言，我们已经解决了：（i）在不同的信噪比水平的扩散参数和特征向量的准确性和精度;（ii）扩散梯度方向编码方案的影响;（iii）最佳B值的扩散张量估计;（iv）骨骼肌T-2的变化的影响;（iv）在不同的信噪比水平的扩散参数和特征向量的准确性和精度。以及最后，SNR对纤维追踪成像的影响和导出的（v）纤维长度、（vi）羽状角和（vii）纤维曲率。我们得出的结论是，骨骼肌的准确DTI需要SNR至少为25，B值在400至500 s/mm（2）之间，并且采集的数据至少有12个扩散梯度方向均匀分布在半球上。此外，对于侧重于骨骼肌损伤或病理的DTI研究，鉴于T-2的混杂效应，需要非常小心地解释弥散参数的明显变化，特别是对于中低SNR值。版权所有（c）2013约翰威利父子有限公司
In this study, we have performed simulations to address the effects of diffusion encoding parameters, signal-to-noise ratio (SNR) and T-2 on skeletal muscle diffusion tensor indices and fiber tracts. Where appropriate, simulations were corroborated and validated by in vivo diffusion tensor imaging (DTI) of human skeletal muscle. Specifically, we have addressed: (i) the accuracy and precision of the diffusion parameters and eigenvectors at different SNR levels; (ii) the effects of the diffusion gradient direction encoding scheme; (iii) the optimal b value for diffusion tensor estimation; (iv) the effects of changes in skeletal muscle T-2; and, finally, the influence of SNR on fiber tractography and derived (v) fiber lengths, (vi) pennation angles and (vii) fiber curvatures. We conclude that accurate DTI of skeletal muscle requires an SNR of at least 25, a b value of between 400 and 500 s/mm(2), and data acquired with at least 12 diffusion gradient directions homogeneously distributed on half a sphere. Furthermore, for DTI studies focusing on skeletal muscle injury or pathology, apparent changes in the diffusion parameters need to be interpreted with great care in view of the confounding effects of T-2, particularly for moderate to low SNR values. Copyright (c) 2013 John Wiley & Sons, Ltd.