Robust Low-Dose CT Sinogram Preprocessing via Exploiting Noise-Generating Mechanism.
Robust Low-Dose CT Sinogram Preprocessing via Exploiting Noise-Generating Mechanism.
复制标题
利用噪声生成机制进行稳健的低剂量 CT 正弦图预处理
DOI：
10.1109/tmi.2017.2767290
复制
发表时间：
2017-12
影响因子：
10.6
通讯作者：
Ma J
中科院分区：
文献类型：
--
作者：
Xie Q;Zeng D;Zhao Q;Meng D;Xu Z;Liang Z;Ma J
计算机断层扫描（CT）图像恢复从低mAs收购没有充分的治疗总是严重退化，由于一些物理因素。在本文中，我们制定了低剂量CT正弦图预处理作为一个标准的最大后验（MAP）估计，它充分考虑了低剂量CT中的两个固有噪声源，即，X射线光子统计和电子噪声背景。此外，而不是使用一个一般的图像之前发现在传统的正弦图恢复模型，我们设计了一个新的先验公式，更合理地编码的分段线性配置的正弦图比以前使用的，如电视先验项。与以往的方法相比，特别是基于MAP的方法，所提出的模型中的似然/损失和先验/正则化项都以更准确的方式得到改进，并且更好地符合实际正弦图生成机制的统计本质。我们进一步构造了一个有效的交替方向方法的乘子算法来解决所提出的MAP框架。对模拟和真实的低剂量CT数据的实验结果表明，该方法在视觉检测和综合定量性能评价方面具有明显的优越性。
Computed tomography (CT) image recovery from low-mAs acquisitions without adequate treatment is always severely degraded due to a number of physical factors. In this paper, we formulate the low-dose CT sinogram preprocessing as a standard maximum a posteriori (MAP) estimation, which takes full consideration of the statistical properties of the two intrinsic noise sources in low-dose CT, i.e., the X-ray photon statistics and the electronic noise background. In addition, instead of using a general image prior as found in the traditional sinogram recovery models, we design a new prior formulation to more rationally encode the piecewise-linear configurations underlying a sinogram than previously used ones, like the TV prior term. As compared with the previous methods, especially the MAP-based ones, both the likelihood/loss and prior/regularization terms in the proposed model are ameliorated in a more accurate manner and better comply with the statistical essence of the generation mechanism of a practical sinogram. We further construct an efficient alternating direction method of multipliers algorithm to solve the proposed MAP framework. Experiments on simulated and real low-dose CT data demonstrate the superiority of the proposed method according to both visual inspection and comprehensive quantitative performance evaluation.