A Quantitative Analysis of the Benefits of Cardiac Gating in Practical Diffusion Tensor Imaging of the Brain
A Quantitative Analysis of the Benefits of Cardiac Gating in Practical Diffusion Tensor Imaging of the Brain
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DOI：
10.1002/mrm.22232
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发表时间：
2010-04-01
影响因子：
3.3
通讯作者：
Morgan, Paul S.
中科院分区：
文献类型：
--
作者：
Habib, Josef;Auer, Dorothee P.;Morgan, Paul S.
在生物医学研究中对定量扩散MRI的需求不断增加，需要重新评估伪影的潜在来源。虽然心脏脉动诱导的影响已经报道过，但在标准采集协议下的定量表征仍然很突出。为了确定实际数据质量改善是否值得使用心脏门控，通过测量和自举模拟定量估计表观扩散系数、分数各向异性和平均扩散率测量中诱导的最大效应。在表观扩散系数时程中，测得心脏脉动效应约占心跳持续时间的6%，在效应幅度上具有相当大的间期差异。Bootstrapping显示，在没有门控的情况下，分数各向异性的高估高达0.26，平均扩散率高达0.19 x 10（-3）mm（2）sec（-1），而在相同的门控模拟中，分数各向异性为0.072（分数各向异性），平均扩散率为0.043 x 10（-3）mm（2）sec（-1）。然而，虽然心脏搏动可能会因此损害部分各向异性和平均扩散率在一些人的量化，我们的数据表明，在组研究中的影响可以忽略不计。Magn Reson Med 63：1098-1103，2010. (C)2010 Wiley-Liss，Inc.
Increasing demand for quantitative diffusion MRI in biomedical research necessitates a reevaluation of potential sources of artifact. While cardiac pulsation-induced effects have been reported previously, their quantitative characterization under standard acquisition protocols remains outstanding. To determine whether practical data quality improvements merit the use of cardiac gating, the maximum effects induced in apparent diffusion coefficient, fractional anisotropy, and mean diffusivity measurements were quantitatively estimated via measurements and bootstrapping simulations. In apparent diffusion coefficient time courses, cardiac pulsation effects were measured to occupy approximately 6% of the heartbeat duration, with considerable intersession differences in effect magnitude. Bootstrapping revealed overestimations in fractional anisotropy up to 0.26, and mean diffusivity up to 0.19 x 10(-3) mm(2) sec(-1) without gating compared to 0.072 (fractional anisotropy) and 0.043 x 10(-3) mm(2) sec(-1) (mean diffusivity) in the same gated simulation. However, while cardiac pulsation may thus impair the quantification of fractional anisotropy and mean diffusivity in some individuals, our data suggested negligible effects in group studies. Magn Reson Med 63:1098-1103, 2010. (C) 2010 Wiley-Liss, Inc.