Improving Fiber Alignment in HARDI by Combining Contextual PDE Flow with Constrained Spherical Deconvolution
Improving Fiber Alignment in HARDI by Combining Contextual PDE Flow with Constrained Spherical Deconvolution
复制标题
通过将上下文 PDE 流与约束球形反卷积相结合来改善 HARDI 中的光纤对准
作者：
Jorg M. Portegies;Rutger Fick;G. Sanguinetti;S. Meesters;G. Girard;R. Duits
我们提出了两种策略来提高根据扩散加权磁共振成像（DW-MRI）数据计算出的纤维束成像结果的质量。两种方法都基于相同的偏微分方程框架，在位置和方向的耦合空间中定义，与描述细长结构增强同时保留交叉结构的随机过程相关联。在第一种方法中，我们使用增强偏微分方程对纤维取向分布 (FOD) 进行上下文正则化，该纤维取向分布 (FOD) 是通过约束球面反卷积 (CSD) 从高角分辨率扩散成像 (HARDI) 数据的单个体素上获得的。因此，我们改进了 FOD 作为后续纤维束成像的输入。其次，我们介绍光纤束相干性（FBC），这是一种量化光纤对准的指标。 FBC 是使用相同的 PDE 框架根据纤维束成像结果计算得出的，并提供了去除杂散纤维的标准。我们验证了所提出的 CSD 和增强模型数据和人体数据的组合，这些数据是通过不同的扫描协议获取的。在模型数据上，我们发现与没有增强的 CSD 相比，PDE 增强可以改善纤维束成像结果的局部指标和全局指标。在人类数据上，我们表明增强功能可以更好地重建交叉纤维束，并且减少纤维束成像输出相对于采集参数的可变性。最后，我们表明，FOD 的增强和纤维束成像中 FBC 测量的使用都提高了概率纤维束成像的不同随机实现的稳定性。这在临床应用中得到了体现：用于癫痫手术规划的视辐射重建。
We propose two strategies to improve the quality of tractography results computed from diffusion weighted magnetic resonance imaging (DW-MRI) data. Both methods are based on the same PDE framework, defined in the coupled space of positions and orientations, associated with a stochastic process describing the enhancement of elongated structures while preserving crossing structures. In the first method we use the enhancement PDE for contextual regularization of a fiber orientation distribution (FOD) that is obtained on individual voxels from high angular resolution diffusion imaging (HARDI) data via constrained spherical deconvolution (CSD). Thereby we improve the FOD as input for subsequent tractography. Secondly, we introduce the fiber to bundle coherence (FBC), a measure for quantification of fiber alignment. The FBC is computed from a tractography result using the same PDE framework and provides a criterion for removing the spurious fibers. We validate the proposed combination of CSD and enhancement on phantom data and on human data, acquired with different scanning protocols. On the phantom data we find that PDE enhancements improve both local metrics and global metrics of tractography results, compared to CSD without enhancements. On the human data we show that the enhancements allow for a better reconstruction of crossing fiber bundles and they reduce the variability of the tractography output with respect to the acquisition parameters. Finally, we show that both the enhancement of the FODs and the use of the FBC measure on the tractography improve the stability with respect to different stochastic realizations of probabilistic tractography. This is shown in a clinical application: the reconstruction of the optic radiation for epilepsy surgery planning.
影响因子：
10.6
作者：
Reisert, Marco;Kiselev, Valerij G.
通讯作者：
Kiselev, Valerij G.