Rekik Islem, Li Gang, Wu Guorong, Lin Weili, Shen Dinggang
Department of Radiology and BRIC, University of North Carolina at Chapel Hill, NC, USA.
Patch Based Tech Med Imaging (2015). 2015 Oct;9467:197-204. doi: 10.1007/978-3-319-28194-0_24. Epub 2016 Jan 8.
Magnetic resonance imaging (MRI) of pediatric brain provides invaluable information for early normal and abnormal brain development. Longitudinal neuroimaging has spanned various research works on examining infant brain development patterns. However, studies on predicting postnatal brain image evolution remain scarce, which is very challenging due to the dynamic tissue contrast change and even inversion in postnatal brains. In this paper, we unprecedentedly propose a dual image intensity and anatomical structure (label) prediction framework that nicely links the geodesic image metamorphosis model with sparse patch-based image representation, thereby defining spatiotemporal metamorphic patches encoding both image photometric and geometric deformation. In the training stage, we learn the 4D metamorphosis trajectories for each training subject. In the prediction stage, we define various strategies to sparsely represent each patch in the testing image using the training metamorphosis patches; as we progressively increment the richness of the patch (from appearance-based to multimodal kinetic patches). We used the proposed framework to predict 6, 9 and 12-month brain MR image intensity and structure (white and gray matter maps) from 3 months in 10 infants. Our seminal work showed promising preliminary prediction results for the spatiotemporally complex, drastically changing brain images.
小儿脑部的磁共振成像(MRI)为早期正常和异常的脑部发育提供了极其宝贵的信息。纵向神经成像涵盖了各种关于检查婴儿脑部发育模式的研究工作。然而,关于预测出生后脑图像演变的研究仍然很少,由于出生后脑组织对比度的动态变化甚至反转,这极具挑战性。在本文中,我们首次提出了一种双图像强度和解剖结构(标签)预测框架,该框架将测地线图像变形模型与基于稀疏补丁的图像表示巧妙地联系起来,从而定义了编码图像光度和几何变形的时空变形补丁。在训练阶段,我们为每个训练对象学习4D变形轨迹。在预测阶段,我们定义了各种策略,使用训练变形补丁稀疏表示测试图像中的每个补丁;随着我们逐步增加补丁的丰富度(从基于外观的补丁到多模态动态补丁)。我们使用所提出的框架对10名婴儿从3个月大时的脑部图像预测6个月、9个月和12个月时的脑磁共振图像强度和结构(白质和灰质图谱)。我们的开创性工作在时空复杂、变化剧烈的脑图像预测方面显示出了有前景的初步结果。