IEEE Trans Med Imaging. 2020 Dec;39(12):4001-4010. doi: 10.1109/TMI.2020.3008930. Epub 2020 Nov 30.
Segmenting anatomical structures in medical images has been successfully addressed with deep learning methods for a range of applications. However, this success is heavily dependent on the quality of the image that is being segmented. A commonly neglected point in the medical image analysis community is the vast amount of clinical images that have severe image artefacts due to organ motion, movement of the patient and/or image acquisition related issues. In this paper, we discuss the implications of image motion artefacts on cardiac MR segmentation and compare a variety of approaches for jointly correcting for artefacts and segmenting the cardiac cavity. The method is based on our recently developed joint artefact detection and reconstruction method, which reconstructs high quality MR images from k-space using a joint loss function and essentially converts the artefact correction task to an under-sampled image reconstruction task by enforcing a data consistency term. In this paper, we propose to use a segmentation network coupled with this in an end-to-end framework. Our training optimises three different tasks: 1) image artefact detection, 2) artefact correction and 3) image segmentation. We train the reconstruction network to automatically correct for motion-related artefacts using synthetically corrupted cardiac MR k-space data and uncorrected reconstructed images. Using a test set of 500 2D+time cine MR acquisitions from the UK Biobank data set, we achieve demonstrably good image quality and high segmentation accuracy in the presence of synthetic motion artefacts. We showcase better performance compared to various image correction architectures.
深度学习方法在医学图像分割方面取得了成功,可应用于多种领域。然而,这种成功在很大程度上依赖于所分割图像的质量。在医学图像分析领域,一个经常被忽视的问题是,由于器官运动、患者运动和/或图像采集相关问题,大量临床图像存在严重的图像伪影。在本文中,我们讨论了图像运动伪影对心脏磁共振分割的影响,并比较了多种联合校正伪影和分割心脏腔的方法。该方法基于我们最近开发的联合伪影检测和重建方法,该方法使用联合损失函数从 k 空间重建高质量的磁共振图像,通过强制数据一致性项,实质上将伪影校正任务转换为欠采样图像重建任务。在本文中,我们提出在端到端框架中使用分割网络来实现这一目标。我们的训练优化了三个不同的任务:1)图像伪影检测,2)伪影校正,3)图像分割。我们使用合成损坏的心脏磁共振 k 空间数据和未校正的重建图像来训练重建网络,以自动校正与运动相关的伪影。使用来自英国生物库数据集的 500 个 2D+时间电影磁共振采集的测试集,我们在存在合成运动伪影的情况下实现了明显良好的图像质量和高分割准确性。与各种图像校正架构相比,我们展示了更好的性能。