[1]牛善洲,吴恒,喻泽峰,等.基于投影数据全广义变分最小化的低剂量CT重建[J].南方医科大学学报,2017,(12):1585.
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基于投影数据全广义变分最小化的低剂量CT重建()
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《南方医科大学学报》[ISSN:/CN:]

卷:
期数:
2017年12期
页码:
1585
栏目:
出版日期:
2017-12-20

文章信息/Info

Title:
Total generalized variation minimization based on projection data for low-dose CT reconstruction
作者:
牛善洲吴恒喻泽峰郑子君喻高航
关键词:
低剂量CT重建全变分全广义变分正则化Gaussian分布滤波反投影算法
Keywords:
low-dose CT reconstruction total variation total generalized variation Gaussian distribution filtered back-projection algorithm
摘要:
目的提出基于投影数据全广义变分最小化的低剂量CT 重建方法。方法首先,通过非线性Anscombe 变换将满足 Poisson 分布的投影数据转化为近似Gaussian 分布,然后基于全广义变分正则化模型对变换后的Gaussian 型数据进行噪声去 除。最后,对去噪的结果进行Anscombe逆变换后实现传统的滤波反投影(FBP)CT重建。结果数值体膜实验结果表明本文提 出的方法可以大大地改进重建图像的质量。FBP方法重建的Clock 和Shepp-Logan 体膜图像的信噪比分别为17.752 dB 和 19.379 dB,本文方法重建的图像的信噪比提高到24.0352 dB 和23.4181 dB。FBP方法重建方法重建的Clock和Shepp-Logan 体膜图像的均方误差分别为0.86%和0.58%,本文方法重建的图像的均方误差降低到到0.2% 和0.23%。结论本文方法可以在 投影数据不满足分段常数假设的前提下去除噪声和条形伪影,从而提高低剂量CT图像重建质量。
Abstract:
Objective To obtain high-quality low-dose CT images using total generalized variation regularization based on the projection data for low-dose CT reconstruction. Methods The projection data of the CT images were transformed from Poisson distribution to Gaussian distribution using the linear Anscombe transform. The transformed data were then restored by an efficient total generalized variation minimization algorithm. Reconstruction was finally achieved by inverse Anscombe transform and filtered back projection (FBP) method. Results The image quality of low-dose CT was greatly improved by the proposed algorithm in both Clock and Shepp-Logan phantoms. The signal-to-noise ratios (SNRs) of the Clock and Shepp- Logan images reconstructed by FBP algorithm were 17.752 dB and 19.379 dB, which were increased by the proposed algorithm to 24.0352 and 23.4181 dB, respectively. The NMSE of the Clock and Shepp-Logan images reconstructed by FBP algorithm was 0.86% and 0.58%, which was reduced by the proposed algorithm to 0.2% and 0.23%, respectively. Conclusion The proposed method can effectively suppress noise and strip artifacts in low-dose CT images when piecewise constant assumption is not possible.
更新日期/Last Update: 1900-01-01