Santos Juan M, Cunningham Charles H, Lustig Michael, Hargreaves Brian A, Hu Bob S, Nishimura Dwight G, Pauly John M
Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA.
Magn Reson Med. 2006 Feb;55(2):371-9. doi: 10.1002/mrm.20765.
Multislice breath-held coronary imaging techniques conventionally lack the coverage of free-breathing 3D acquisitions but use a considerably shorter acquisition window during the cardiac cycle. This produces images with significantly less motion artifact but a lower signal-to-noise ratio (SNR). By using the extra SNR available at 3 T and undersampling k-space without introducing significant aliasing artifacts, we were able to acquire high-resolution fat-suppressed images of the whole heart in 17 heartbeats (a single breath-hold). The basic pulse sequence consists of a spectral-spatial excitation followed by a variable-density spiral readout. This is combined with real-time localization and a real-time prospective shim correction. Images are reconstructed with the use of gridding, and advanced techniques are used to reduce aliasing artifacts.
传统的多层屏气冠状动脉成像技术通常缺乏自由呼吸三维采集的覆盖范围，但在心动周期中使用的采集窗口要短得多。这产生的图像运动伪影明显减少，但信噪比（SNR）较低。通过利用3T时可用的额外信噪比并对k空间进行欠采样而不引入明显的混叠伪影，我们能够在17次心跳（单次屏气）内获取整个心脏的高分辨率脂肪抑制图像。基本脉冲序列包括频谱空间激发，随后是可变密度螺旋读出。这与实时定位和实时前瞻性匀场校正相结合。使用网格化重建图像，并使用先进技术减少混叠伪影。
