SNR-weighted sinogram smoothing with improved noise-resolution properties for low-dose x-ray computed tomography

2004 ◽  
Author(s):  
Tianfang Li ◽  
Jing Wang ◽  
Junhai Wen ◽  
Xiang Li ◽  
Hongbing Lu ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Low Dose ◽  
X Ray ◽  
X Ray Computed

scholarly journals Low-Dosed X-Ray Computed Tomography Imaging by Regularized Fully Spatial Fractional-Order Perona-Malik Diffusion

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Zhiwu Liao
Keyword(s):  
Computed Tomography ◽  
Fractional Order ◽  
Low Dose ◽  
Computed Tomography Imaging ◽  
Edge Preserving ◽  
X Ray ◽  
Good Ability ◽  
X Ray Computed ◽  
The Right ◽  
Low Dose Computed Tomography

Existing fractional-order Perona-Malik Diffusion (FOPMD) algorithms used in noise suppressing suffer from undesired artifacts and speckle effect, which hamper FOPMD used in low-dosed X-ray computed tomography (LDCT) imaging. In this paper, we propose a new FOPMD method for low-dose computed tomography (LDCT) imaging, which is called regularized fully spatial FOPMD (RFS-FOPMD), whose numerical scheme is also given based on Grünwald-Letnikov derivative (G-L derivative). Here, fully spatial FOPMD represents all the integer-order derivatives (IODs) in the right hand of Perona-Malik Diffusion (PMD) which are replaced by fractional-order derivatives (FODs). Since the new scheme has advantages of both regularization and FOPMD, it has good abilities in singularities preserving while suppressing noise. Some real sinogram of LDCT are used to compare the different performances not only for some classical but also for some state-of-art diffusion schemes. These schemes include PMD, regularized PMD (RPMD), and FOPMD in (Hu et al. 2012). Experimental results show that besides good ability in edge preserving, the new scheme also has good stability for iteration number and can avoid artifacts and speckle effect with suitable parameters.

Low-dose low-scattering X-ray computed tomography with high-spatial-energy resolutions using a cooled cadmium telluride detector

2019 ◽  
Vol 199 ◽  
pp. 62-69 ◽  
Author(s):  
Hodaka Moriyama ◽  
Manabu Watanabe ◽  
Shinya Kusachi ◽  
Yasuyuki Oda ◽  
Eiichi Sato
Keyword(s):  
Computed Tomography ◽  
Cadmium Telluride ◽  
Low Dose ◽  
X Ray ◽  
X Ray Computed

scholarly journals Noise Estimation for Single-Slice Sinogram of Low-Dose X-Ray Computed Tomography Using Homogenous Patch

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Zhiwu Liao ◽  
Shaoxiang Hu ◽  
Ming Li ◽  
Wufan Chen
Keyword(s):  
Computed Tomography ◽  
Noise Level ◽  
Low Dose ◽  
Noise Estimation ◽  
X Ray ◽  
Single Slice ◽  
Center Point ◽  
Manual Selection ◽  
X Ray Computed ◽  
Selection Of

We present a new method to estimate noise for a single-slice sinogram of low-dose CT based on the homogenous patches centered at a special pixel, called center point, which has the smallest variance among all sinogram pixels. The homogenous patch, composed by homogenous points, is formed by the points similar to the center point using similarity sorting, similarity decreasing searching, and variance analysis in a very large neighborhood (VLN) to avoid manual selection of parameter for similarity measures.Homogenous pixels in the VLN allow us find the largest number of samples, who have the highest similarities to the center point, for noise estimation, and the noise level can be estimated according to unbiased estimation.Experimental results show that for the simulated noisy sinograms, the method proposed in this paper can obtain satisfied noise estimation results, especially for sinograms with relatively serious noises.

Bayesian sinogram smoothing with an anisotropic diffusion weighted prior for low-dose X-ray computed tomography

Optik ◽  
2013 ◽  
Vol 124 (17) ◽  
pp. 2811-2816 ◽  
Author(s):  
Quan Zhang ◽  
Zhiguo Gui ◽  
Yang Chen ◽  
Yuanjin Li ◽  
Limin Luo
Keyword(s):  
Computed Tomography ◽  
Anisotropic Diffusion ◽  
Low Dose ◽  
X Ray ◽  
Diffusion Weighted ◽  
X Ray Computed

scholarly journals Low-dose exposure energy-resolved X-ray computed tomography using a contrast agent with a high-energy K-edge

2013 ◽  
Vol 51 (1) ◽  
pp. 91-97 ◽  
Author(s):  
Yoshiki Yamashita ◽  
Kazunari Shima ◽  
Ikuo Kanno ◽  
Masahiko Ohtaka ◽  
Makoto Hashimoto ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Contrast Agent ◽  
Low Dose ◽  
High Energy ◽  
X Ray ◽  
X Ray Computed ◽  
Exposure Energy

scholarly journals Low-dose X-ray computed tomography image reconstruction with a combined low-mAs and sparse-view protocol

2014 ◽  
Vol 22 (12) ◽  
pp. 15190 ◽  
Author(s):  
Yang Gao ◽  
Zhaoying Bian ◽  
Jing Huang ◽  
Yunwan Zhang ◽  
Shanzhou Niu ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Image Reconstruction ◽  
Low Dose ◽  
X Ray ◽  
Tomography Image ◽  
X Ray Computed ◽  
Computed Tomography Image
Sign in / Sign up

Export Citation Format

Share Document