Accelerated two-dimensional cine DENSE cardiovascular magnetic resonance using compressed sensing and parallel imaging
Accelerated two-dimensional cine DENSE cardiovascular magnetic resonance using compressed sensing and parallel imaging
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DOI：
10.1186/s12968-016-0253-2
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发表时间：
2016-06-14
影响因子：
6.4
通讯作者：
Epstein, Frederick H.
中科院分区：
文献类型：
--
作者：
Chen, Xiao;Yang, Yang;Epstein, Frederick H.
背景：电影置换编码与刺激回声(密集)提供准确的心脏力学定量成像和快速的位移和应变分析，但图像采集时间相对较长。采用并行成像(PI)的压缩传感(CS)通常可以提供从低于奈奎斯特速率的采样数据中恢复的高质量图像。本研究的目的是建立CS-PI电影密度的加速采集和重建方法，评估其在回溯性欠采样心脏成像中的准确性，并论证其在单次呼吸中用于预期加速的2D电影密度成像的可行性。方法：采用变密度螺旋k空间采样和随时间旋转的黄金角度加速电影密度序列。将一种CS方法--带运动引导的块低阶稀疏性(BLOSM)与灵敏度编码(SENSE)相结合，用于欠采样多线圈螺旋数据的重建。7名健康志愿者和7名患者接受了2D电影高密度成像，包括全采样采集(持续时间为14-26次)和预期的速率2和速率4加速采集(持续时间为14和8次)。使用BLOSM-SENSE和SENSE重建回溯性和前瞻性加速的数据。使用相对均方根误差(RRMSE)量化回溯性欠采样数据的图像质量。结果：对于回溯性欠采样数据，BLOSM-SENSE在Rate-2处的RRMSE与在Rate-4处的RRMSE更低(p<；0.05，ANOVA)。同样，对于回溯性欠采样，BLOSM-SENSE与参考位移和应变数据在速率2时的相关性相似或更好，在速率4加速时的相关性比SENSE更好。Bland-Altman分析显示，与回溯性抽样不足的数据相比，BLOSM-SENSE对于速率-2的位移和应变数据的一致性相似或更好，而在速率-4的情况下BLOSM-SENSE的一致性更好。Rate-2和Rate-4预期加速电影密度成像提供了良好的图像质量和位移和应变的期望值。结论：BLOSM-Sense-Accelerated螺旋电影二维位移编码电影密度成像可以在8~14次心跳的一次屏气中获得高质量的图像，并准确地评估心肌位移和周向应变。
Background: Cine Displacement Encoding with Stimulated Echoes (DENSE) provides accurate quantitative imaging of cardiac mechanics with rapid displacement and strain analysis; however, image acquisition times are relatively long. Compressed sensing (CS) with parallel imaging (PI) can generally provide high-quality images recovered from data sampled below the Nyquist rate. The purposes of the present study were to develop CS-PI-accelerated acquisition and reconstruction methods for cine DENSE, to assess their accuracy for cardiac imaging using retrospective undersampling, and to demonstrate their feasibility for prospectively-accelerated 2D cine DENSE imaging in a single breathhold.Methods: An accelerated cine DENSE sequence with variable-density spiral k-space sampling and golden angle rotations through time was implemented. A CS method, Block LOw-rank Sparsity with Motion-guidance (BLOSM), was combined with sensitivity encoding (SENSE) for the reconstruction of under-sampled multi-coil spiral data. Seven healthy volunteers and 7 patients underwent 2D cine DENSE imaging with fully-sampled acquisitions (14-26 heartbeats in duration) and with prospectively rate-2 and rate-4 accelerated acquisitions (14 and 8 heartbeats in duration). Retrospectively-and prospectively-accelerated data were reconstructed using BLOSM-SENSE and SENSE. Image quality of retrospectively-undersampled data was quantified using the relative root mean square error (rRMSE). Myocardial displacement and circumferential strain were computed for functional assessment, and linear correlation and Bland-Altman analyses were used to compare accelerated acquisitions to fully-sampled reference datasets.Results: For retrospectively-undersampled data, BLOSM-SENSE provided similar or lower rRMSE at rate-2 and lower rRMSE at rate-4 acceleration compared to SENSE (p < 0.05, ANOVA). Similarly, for retrospective undersampling, BLOSM-SENSE provided similar or better correlation with reference displacement and strain data at rate-2 and better correlation at rate-4 acceleration compared to SENSE. Bland-Altman analyses showed similar or better agreement for displacement and strain data at rate-2 and better agreement at rate-4 using BLOSM-SENSE compared to SENSE for retrospectively-undersampled data. Rate-2 and rate-4 prospectively-accelerated cine DENSE provided good image quality and expected values of displacement and strain.Conclusions: BLOSM-SENSE-accelerated spiral cine DENSE imaging with 2D displacement encoding can be acquired in a single breathhold of 8-14 heartbeats with high image quality and accurate assessment of myocardial displacement and circumferential strain.