论文标题
动态对比增强磁共振断层扫描中的参数选择
Parameter selection in dynamic contrast-enhanced magnetic resonance tomography
论文作者
论文摘要
在这项工作中，我们考虑了稀疏采样动态对比增强（DCE）磁共振成像（MRI）的图像重建问题。 DCE-MRI是一种在静脉造影剂给药之前，期间和之后获取一系列MR图像的技术，它用于研究微血管结构和灌注。为了克服相关时空逆问题的不良性，我们使用正则化。在正规化中，主要问题之一是如何确定控制数据拟合项和正则化项之间平衡的正则化参数。选择此参数的大多数方法都需要计算大量估计值，即使在固定问题中也是如此。在动态成像中，由于空间和时间正则功能需要单独的正则参数，因此参数选择更加耗时。在这项工作中，我们研究了将S-Curve与DCE-MR数据一起使用的可能性。我们使用S-Curve选择空间正则化参数，将时间正则化参数作为重建问题中的唯一自由参数。在这项工作中，通过计算具有几个时间正则化参数值的重建，可以手动选择时间正则化参数。
In this work we consider the image reconstruction problem of sparsely sampled dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). DCE-MRI is a technique for acquiring a series of MR images before, during and after intravenous contrast agent administration, and it is used to study microvascular structure and perfusion. To overcome the ill-posedness of the related spatio-temporal inverse problem, we use regularization. In regularization one of the main problems is how to determine the regularization parameter which controls the balance between data fitting term and regularization term. Most methods for selecting this parameter require the computation of a large number of estimates even in stationary problems. In dynamic imaging, the parameter selection is even more time consuming since separate regularization parameters are needed for the spatial and temporal regularization functionals. In this work, we study the possibility of using the S-curve with DCE-MR data. We select the spatial regularization parameter using the S-curve, leaving the temporal regularization parameter as the only free parameter in the reconstruction problem. In this work, the temporal regularization parameter is selected manually by computing reconstructions with several values of the temporal regularization parameter.
