论文标题
深层生成扩散模型加速运动校正
Accelerated Motion Correction with Deep Generative Diffusion Models
论文作者
论文摘要
磁共振成像(MRI)是一种强大的医学成像方式,但不幸的是,扫描时间很长,除了增加操作成本外,还可以导致由于患者运动而导致图像伪像。在获取过程中的运动导致在图像重建过程中不明显的测量数据中的不一致,这些数据表现为模糊和幽灵。已经提出了各种基于深度学习的重建技术,通过减少高保真度重建图像所需的测量数量来减少扫描时间。此外,深度学习已用于使用端到端技术纠正运动。但是,这增加了在测试时间(采样模式,运动水平)的分布变化的敏感性。在这项工作中,我们提出了一个框架,用于共同重建高度亚采样的MRI数据,同时使用基于扩散的生成模型估算患者运动。我们的方法在训练时没有对采样轨迹或运动模式进行特定的假设,因此可以灵活地应用于各种类型的测量模型和患者运动。我们展示了我们的回顾性加速2D大脑MRI的框架。
Magnetic Resonance Imaging (MRI) is a powerful medical imaging modality, but unfortunately suffers from long scan times which, aside from increasing operational costs, can lead to image artifacts due to patient motion. Motion during the acquisition leads to inconsistencies in measured data that manifest as blurring and ghosting if unaccounted for in the image reconstruction process. Various deep learning based reconstruction techniques have been proposed which decrease scan time by reducing the number of measurements needed for a high fidelity reconstructed image. Additionally, deep learning has been used to correct motion using end-to-end techniques. This, however, increases susceptibility to distribution shifts at test time (sampling pattern, motion level). In this work we propose a framework for jointly reconstructing highly sub-sampled MRI data while estimating patient motion using diffusion based generative models. Our method does not make specific assumptions on the sampling trajectory or motion pattern at training time and thus can be flexibly applied to various types of measurement models and patient motion. We demonstrate our framework on retrospectively accelerated 2D brain MRI corrupted by rigid motion.