Department of Medicine, The University of Chicago, Chicago, IL, USA.
Department of Radiology, The University of Chicago, Chicago, IL, USA.
Med Phys. 2017 Jul;44(7):3450-3463. doi: 10.1002/mp.12234. Epub 2017 May 23.
To introduce a pair of accelerated non-Cartesian acquisition principles that when combined, exploit the periodicity of k-space acquisition, and thereby enable acquisition of high-temporal cine Cardiac Magnetic Resonance (CMR).
The mathematical formulation of a noniterative, undersampled non-Cartesian cine acquisition and reconstruction is presented. First, a low-pass filtering step that exploits streaking artifact redundancy is provided (i.e., Dynamically Interleaved Streak removal in the Power-spectrum Encoded domain with Low-pass filtering [DISPEL]). Next, an effective radial acquisition for the DISPEL approach that exploits the property of prime numbers is described (i.e., Modulo-Prime Spoke [MoPS]). Both DISPEL and MoPS are examined using numerical simulation of a digital heart phantom to show that high-temporal cine-CMR is feasible without removing physiologic motion vs aperiodic interleaving using Golden Angles. The combined high-temporal cine approach is next examined in 11 healthy subjects for a time-volume curve assessment of left ventricular systolic and diastolic performance vs conventional Cartesian cine-CMR reference.
The DISPEL method was first shown using simulation under different streak cycles to allow separation of undersampled radial streaking artifacts from physiologic motion with a sufficiently frequent streak-cycle interval. Radial interleaving with MoPS is next shown to allow interleaves with pseudo-Golden-Angle variants, and be more compatible with DISPEL against irrational and nonperiodic rotation angles, including the Golden-Angle-derived rotations. In the in vivo data, the proposed method showed no statistical difference in the systolic performance, while diastolic parameters sensitive to the cine's temporal resolution were statistically significant (P < 0.05 vs Cartesian cine).
We demonstrate a high-temporal resolution cine-CMR using DISPEL and MoPS, whose streaking artifact was separated from physiologic motion.
介绍一对加速的非笛卡尔采集原理,当它们结合使用时,可以利用 k 空间采集的周期性,从而实现高时间分辨率的心脏磁共振(CMR)电影采集。
介绍了一种非迭代、欠采样的非笛卡尔电影采集和重建的数学公式。首先,提供了一种利用条纹伪影冗余的低通滤波步骤(即在功率谱编码域中利用低通滤波的动态交错条纹去除[DISPEL])。其次,描述了一种用于 DISPEL 方法的有效径向采集,该方法利用了素数的性质(即模数-素线[MoPS])。使用数字心脏模型的数值模拟来检查 DISPEL 和 MoPS,以证明在不消除生理运动的情况下,使用 MoPS 可以实现高时间分辨率的电影-CMR,而不是使用非周期性交错的 Golden Angles。接下来,在 11 名健康受试者中,使用组合的高时间分辨率电影方法进行左心室收缩和舒张功能的时间-容积曲线评估,与传统的笛卡尔电影-CMR 参考进行比较。
首先在不同条纹周期下使用模拟显示 DISPEL 方法,以便在具有足够频繁的条纹周期间隔下,将欠采样的径向条纹伪影与生理运动分离。接下来显示 MoPS 的径向交错可以允许具有伪 Golden-Angle 变体的交错,并与 DISPEL 更兼容,以应对不合理和非周期性的旋转角度,包括由 Golden-Angle 衍生的旋转角度。在体内数据中,该方法在收缩性能方面没有统计学差异,而对电影时间分辨率敏感的舒张参数则具有统计学意义(与笛卡尔电影相比,P<0.05)。
我们展示了一种使用 DISPEL 和 MoPS 的高时间分辨率电影-CMR,其条纹伪影与生理运动分离。