-
基于深度学习的磁共振成像(magnetic resonance imaging, MRI)方法需要大规模、高质量的病患数据样本集进行预训练. 然而, 由于病患隐私及设备等因素限制, 获取大规模、高质量的磁共振数据集在实际临床应用中面临挑战. 本文提出一种新的基于深度学习的欠采样磁共振图像重建方法, 该方法无需预训练、不依赖训练数据集, 而是充分利用待重建的目标MR图像的结构先验和支撑先验, 并将其引入深度图像先验(deep image prior, DIP)框架, 从而削减对训练数据集的依赖, 提升学习效率. 基于参考图像与目标图像的相似性, 采用高分辨率参考图像作为深度网络输入, 将结构先验信息引入网络; 将参考图像在小波域中幅值大的系数索引集作为目标图像的已知支撑集, 构造正则化约束项, 将网络训练转化为网络参数的最优化求解过程. 实验结果表明, 本文方法可由欠采样k空间数据重建得到更精确的磁共振图像, 且在保留组织特征、细节纹理方面具有明显优势.Magnetic resonance imaging (MRI) method based on deep learning needs large-quantity and high-quality patient-based datasets for pre-training. However, this is a challenge to the clinical applications because it is difficult to obtain a sufficient quantity of patient-based MR datasets due to the limitation of equipment and patient privacy concerns. In this paper, we propose a novel undersampled MRI reconstruction method based on deep learning. This method does not require any pre-training procedures and does not depend on training datasets. The proposed method is inspired by the traditional deep image prior (DIP) framework, and integrates the structure prior and support prior of the target MR image to improve the efficiency of learning. Based on the similarity between the reference image and the target image, the high-resolution reference image obtained in advance is used as the network input, thereby incorporating the structural prior information into network. By taking the coefficient index set of the reference image with large amplitude in the wavelet domain as the known support of the target image, the regularization constraint term is constructed, and the network training is transformed into the optimization process of network parameters. Experimental results show that the proposed method can obtain more accurate reconstructions from undersampled k-space data, and has obvious advantages in preserving tissue features and detailed texture.
-
Keywords:
- magnetic resonance imaging /
- undersampled image reconstruction /
- deep image prior /
- support prior








下载: