School of Computer Science, Sichuan University, Chengdu, Sichuan, 610065, China.
School of Computer Science, Chengdu University of Information Technology, Chengdu, Sichuan, China.
Med Phys. 2021 Jul;48(7):3778-3789. doi: 10.1002/mp.14929. Epub 2021 Jun 7.
Different Magnetic resonance imaging (MRI) modalities of the same anatomical structure are required to present different pathological information from the physical level for diagnostic needs. However, it is often difficult to obtain full-sequence MRI images of patients owing to limitations such as time consumption and high cost. The purpose of this work is to develop an algorithm for target MRI sequences prediction with high accuracy, and provide more information for clinical diagnosis.
We propose a deep learning-based multi-modal computing model for MRI synthesis with feature disentanglement strategy. To take full advantage of the complementary information provided by different modalities, multi-modal MRI sequences are utilized as input. Notably, the proposed approach decomposes each input modality into modality-invariant space with shared information and modality-specific space with specific information, so that features are extracted separately to effectively process the input data. Subsequently, both of them are fused through the adaptive instance normalization (AdaIN) layer in the decoder. In addition, to address the lack of specific information of the target modality in the test phase, a local adaptive fusion (LAF) module is adopted to generate a modality-like pseudo-target with specific information similar to the ground truth.
To evaluate the synthesis performance, we verify our method on the BRATS2015 dataset of 164 subjects. The experimental results demonstrate our approach significantly outperforms the benchmark method and other state-of-the-art medical image synthesis methods in both quantitative and qualitative measures. Compared with the pix2pixGANs method, the PSNR improves from 23.68 to 24.8. Moreover the ablation studies have also verified the effectiveness of important components of the proposed method.
The proposed method could be effective in prediction of target MRI sequences, and useful for clinical diagnosis and treatment.
为了满足诊断需求,同一解剖结构的不同磁共振成像(MRI)模态需要从物理层面呈现不同的病理信息。然而,由于时间消耗和成本高等限制,通常难以获取患者的全序列 MRI 图像。本研究旨在开发一种具有高精度的目标 MRI 序列预测算法,为临床诊断提供更多信息。
我们提出了一种基于深度学习的多模态计算模型,用于具有特征解缠策略的 MRI 合成。为了充分利用不同模态提供的互补信息,多模态 MRI 序列被用作输入。值得注意的是,所提出的方法将每个输入模态分解为具有共享信息的模态不变空间和具有特定信息的模态特定空间,以便分别提取特征,从而有效地处理输入数据。随后,通过解码器中的自适应实例归一化(AdaIN)层融合两者。此外,为了解决测试阶段目标模态特定信息不足的问题,采用局部自适应融合(LAF)模块生成具有与真实值相似特定信息的模态似伪目标。
为了评估合成性能,我们在 BRATS2015 数据集上对 164 名受试者进行了验证。实验结果表明,我们的方法在定量和定性指标上均显著优于基准方法和其他最先进的医学图像合成方法。与 pix2pixGANs 方法相比,PSNR 从 23.68 提高到 24.8。此外,消融研究也验证了所提出方法的重要组成部分的有效性。
所提出的方法可以有效地预测目标 MRI 序列,有助于临床诊断和治疗。