论文标题
动态平行MR图像重建的互补时频域网络
Complementary Time-Frequency Domain Networks for Dynamic Parallel MR Image Reconstruction
论文作者
论文摘要
目的:通过学习互补的时频域网络,引入一种基于深度学习的新型方法,用于快速和高质量的动态多型MR重建,该网络可以从互补域中同时利用时空相关性。 理论和方法:动态平行的MR图像重建是一个多变量最小化问题,其中数据在合并的时间傅立叶和空间(X-F)结构域以及时空图像(X-T)域中正规化。得出了基于可变拆分技术的迭代算法,该算法在X-F和X-T空间中的信号去敏化步骤中交替,封闭形式的数据一致性步骤和加权耦合步骤。迭代模型嵌入了一个深层的复发神经网络中,该网络学会通过利用互补域中的时空冗余来恢复图像。 结果:在两个高度不足的多圈心脏心脏Cine MRI扫描的数据集上进行了实验。结果表明,我们提出的方法在定量和定性上都优于当前的最新方法。所提出的模型还可以很好地推广到从不同的扫描仪中获取的数据,以及具有在训练集中没有看到的病理学的数据。 结论:这项工作显示了与深层神经网络互补的时频域中重建动态平行MRI的好处。该方法可以通过快速重建速度(2.8s)的高度采样动态多线圈数据($ 16 \ times $ and $ 16 \ times $ and $ 16 \ times $和$ 24 \ times $)从高度不足的动态多线圈数据($ 16 \ times $和$ 24 \ times $产生15s和10s扫描时间)中有效,可靠地重建高质量的图像。这有可能有助于实现快速的单呼吸临床2D心脏电影成像。
Purpose: To introduce a novel deep learning based approach for fast and high-quality dynamic multi-coil MR reconstruction by learning a complementary time-frequency domain network that exploits spatio-temporal correlations simultaneously from complementary domains. Theory and Methods: Dynamic parallel MR image reconstruction is formulated as a multi-variable minimisation problem, where the data is regularised in combined temporal Fourier and spatial (x-f) domain as well as in spatio-temporal image (x-t) domain. An iterative algorithm based on variable splitting technique is derived, which alternates among signal de-aliasing steps in x-f and x-t spaces, a closed-form point-wise data consistency step and a weighted coupling step. The iterative model is embedded into a deep recurrent neural network which learns to recover the image via exploiting spatio-temporal redundancies in complementary domains. Results: Experiments were performed on two datasets of highly undersampled multi-coil short-axis cardiac cine MRI scans. Results demonstrate that our proposed method outperforms the current state-of-the-art approaches both quantitatively and qualitatively. The proposed model can also generalise well to data acquired from a different scanner and data with pathologies that were not seen in the training set. Conclusion: The work shows the benefit of reconstructing dynamic parallel MRI in complementary time-frequency domains with deep neural networks. The method can effectively and robustly reconstruct high-quality images from highly undersampled dynamic multi-coil data ($16 \times$ and $24 \times$ yielding 15s and 10s scan times respectively) with fast reconstruction speed (2.8s). This could potentially facilitate achieving fast single-breath-hold clinical 2D cardiac cine imaging.