Thoracic low-dose CT image processing using an artifact suppressed large-scale nonlocal means
Open Access
- 13 April 2012
- journal article
- Published by IOP Publishing in Physics in Medicine & Biology
- Vol. 57 (9), 2667-2688
- https://doi.org/10.1088/0031-9155/57/9/2667
Abstract
The x-ray exposure to patients has become a major concern in computed tomography (CT) and minimizing the radiation exposure has been one of the major efforts in the CT field. Due to plenty high-attenuation tissues in the human chest, under low-dose scan protocols, thoracic low-dose CT (LDCT) images tend to be severely degraded by excessive mottled noise and non-stationary streak artifacts. Their removal is rather a challenging task because the streak artifacts with directional prominence are often hard to discriminate from the attenuation information of normal tissues. This paper describes a two-step processing scheme called 'artifact suppressed large-scale nonlocal means' for suppressing both noise and artifacts in thoracic LDCT images. Specific scale and direction properties were exploited to discriminate the noise and artifacts from image structures. Parallel implementation has been introduced to speed up the whole processing by more than 100 times. Phantom and patient CT images were both acquired for evaluation purpose. Comparative qualitative and quantitative analyses were both performed that allows conclusion on the efficacy of our method in improving thoracic LDCT data.Keywords
This publication has 28 references indexed in Scilit:
- Image restoration and spatial resolution in 7‐tesla magnetic resonance imagingMagnetic Resonance in Medicine, 2010
- The reduction of image noise and streak artifact in the thoracic inlet during low dose and ultra-low dose thoracic CTPhysics in Medicine & Biology, 2010
- Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CTPhysics in Medicine & Biology, 2009
- Use of 3D Adaptive Raw-Data Filter in CT of the Lung: Effect on Radiation Dose ReductionAmerican Journal of Roentgenology, 2008
- Statistical reconstruction for x-ray CT systems with non-continuous detectorsPhysics in Medicine & Biology, 2006
- Screening for lung cancer using low dose CT scanning: results of 2 year follow upThorax, 2005
- Screening for lung cancer using low dose CT scanningThorax, 2004
- Nonlinear approximation and the space BV[inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="01i" /]American Journal of Mathematics, 1999
- The discrete wavelet transform: wedding the a trous and Mallat algorithmsIEEE Transactions on Signal Processing, 1992
- STATISTICAL METHODS FOR ASSESSING AGREEMENT BETWEEN TWO METHODS OF CLINICAL MEASUREMENTThe Lancet, 1986