Assessment of motion gating strategies for mouse magnetic resonance at high magnetic fields
Assessment of motion gating strategies for mouse magnetic resonance at high magnetic fields
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DOI：
10.1002/jmri.10454
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发表时间：
2004-02-01
影响因子：
4.4
通讯作者：
Clarke, K
中科院分区：
文献类型：
--
作者：
Cassidy, PJ;Schneider, JE;Clarke, K
目的：通过量化体内图像和光谱中观察到的运动伪影水平，评估高磁场下小鼠心脏磁共振（MR）运动门控策略的性能。材料和方法：心脏、横膈膜和肝脏的MR成像（MRI）;主动脉弓的MR血管造影;在11.75T下对麻醉的C57 B1/6小鼠进行心脏的切片选择性H-1光谱学。门控信号是使用定制的生理运动门控设备导出的，并且考虑的门控策略是无门控、心脏门控、常规门控（即，呼吸期间的空白）、自动门控和用户定义门控。自动和用户定义模式均使用心脏和呼吸门控，并在呼吸期间保持稳态。门控性能通过量化图像中观察到的运动伪影水平以及频谱中的幅度和相位稳定性程度进行评估。结果：在呼吸期间具有稳态维持的用户定义门控为小鼠心脏成像、血管造影和光谱提供了最佳性能，与仅心脏门控相比，信号强度增加了3倍，噪声强度降低了6倍。在高磁场下，呼吸期间具有稳态维持的生理门控对于小鼠心脏MR至关重要。
Purpose: To assess the performance of motion gating strategies for mouse cardiac magnetic resonance (MR) at high magnetic fields by quantifying the levels of motion artifact observed in images and spectra in vivo.Materials and Methods: MR imaging (MRI) of the heart, diaphragm, and liver; MR angiography of the aortic arch; and slice-selective H-1-spectroscopy of the heart were performed on anesthetized, C57B1/6 mice at 11.75 T. Gating signals were derived using a custom-built physiological motion gating device, and the gating strategies considered were no gating, cardiac gating, conventional gating (i.e., blanking during respiration), automatic gating, and user-defined gating. Both automatic and user-defined modes used cardiac and respiratory gating with steady-state maintenance during respiration. Gating performance was assessed by quantifying the levels of motion artifact observed in images and the degree of amplitude and phase stability in spectra.Results: User-defined gating with steady-state maintenance during respiration gave the best performance for mouse cardiac imaging, angiography, and spectroscopy, with a threefold increase in signal intensity and a sixfold reduction in noise intensity compared to cardiac gating only.Conclusion: Physiological gating with steady-state maintenance during respiration is essential for mouse cardiac MR at high magnetic fields.