超短回波时间（ultra-short echo-time，UTE）成像在科研和临床诊断上有着良好的应用前景，但是其k空间轨迹极易受到梯度涡流和梯度延时等因素的影响而产生失真，会严重影响磁共振图像重建的质量．该文分析了轨迹失真对UTE图像的影响，并提出了一种改进的轨迹失真校正方法．实验表明，该方法能够明显减轻UTE图像中轨迹失真的影响、改善图像质量，还可以降低UTE技术对磁共振成像（MRI）硬件系统性能的要求，有助于UTE方法的推广．
张志
,
王超
,
周波
,
杨春升
,
陈方
,
刘朝阳
. 超短回波时间成像k空间轨迹失真的校正[J]. 波谱学杂志, 2016
, 33(4)
: 597
-608
.
DOI: 10.11938/cjmr20160409
Ultra-short echo-time (UTE) imaging has many potential applications in clinical diagnosis and scientific researches. Image quality in UTE can be degraded by imperfections in k-space trajectory resulting from eddy currents, gradient delay and so on. In this work, an improved method for k-space trajectory correction in UTE was proposed. Experimental results showed that this method could correct back effects of the trajectory errors, and improve the quality of UTE images significantly. In addition, with the use of the method, UTE would have lower performance requirement for magnetic resonance imaging (MRI) hardware system, which is beneficial for development of routine UTE applications.
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