arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2009.03008eess.IVcs.CVcs.LG
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扩散中的学习最优q空间采样方法MRI

Towards learned optimal q-space sampling in diffusion MRI

Technion(以色列理工学院);University of Waterloo(滑铁卢大学)

Tomer Weiss, Sanketh Vedula, Ortal Senouf, Oleg Michailovich, AlexBronstein

摘要:

纤维束成像是一种重要的计算神经科学工具,可以重建大脑白质的空间连接和组织。纤维束成像利用弥散磁共振成像(dMRI),可以测量大脑水沿不同空间方向的表观扩散率。不幸的是,收集这些数据的代价是空间分辨率降低和采集时间大大增加,这限制了dMRI的临床应用。到目前为止,这一问题已通过两项主要战略得到解决。大多数的努力已经扩展到提高任何,但固定的采样方案(定义通过选择的扩散编码梯度)的信号估计的质量。另一方面,对抽样方案的优化也被证明是有效的。受前人研究成果的启发,本文将上述策略整合到一个统一的估计框架中,在该框架中,估计模型和抽样设计{ \it并发}进行优化。所提出的解决方案提供了实质性的改善,信号估计的质量,以及随后的分析的准确性,通过纤维追踪。虽然证明学习的估计模型的最优性可能需要更广泛的评估,但我们声称学习的采样方案可以立即使用,提供了一种改进dMRI分析的方法,而无需部署用于估计的神经网络。我们提出了一个全面的比较分析的基础上人类连接组计划的数据。代码和学习的抽样设计可在https://github.com/tomer196/Learned_dMRI上获得。

英文摘要:

Fiber tractography is an important tool of computational neuroscience that enables reconstructing the spatial connectivity and organization of white matter of the brain. Fiber tractography takes advantage of diffusion Magnetic Resonance Imaging (dMRI) which allows measuring the apparent diffusivity of cerebral water along different spatial directions. Unfortunately, collecting such data comes at the price of reduced spatial resolution and substantially elevated acquisition times, which limits the clinical applicability of dMRI. This problem has been thus far addressed using two principal strategies. Most of the efforts have been extended towards improving the quality of signal estimation for any, yet fixed sampling scheme (defined through the choice of diffusion-encoding gradients). On the other hand, optimization over the sampling scheme has also proven to be effective. Inspired by the previous results, the present work consolidates the above strategies into a unified estimation framework, in which the optimization is carried out with respect to both estimation model and sampling design {\it concurrently}. The proposed solution offers substantial improvements in the quality of signal estimation as well as the accuracy of ensuing analysis by means of fiber tractography. While proving the optimality of the learned estimation models would probably need more extensive evaluation, we nevertheless claim that the learned sampling schemes can be of immediate use, offering a way to improve the dMRI analysis without the necessity of deploying the neural network used for their estimation. We present a comprehensive comparative analysis based on the Human Connectome Project data. Code and learned sampling designs aviliable at https://github.com/tomer196/Learned_dMRI.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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