DocumentCode :
3206378
Title :
Experiment-based scatter correction for cone-beam computed tomography using the statistical method
Author :
Aootaphao, Sorapong ; Thongvigitmanee, Saowapak S. ; Rajruangrabin, Jartuwat ; Junhunee, Parinya ; Thajchayapong, P.
Author_Institution :
Image Technol. Lab., Nat. Electron. & Comput. Technol. Center, Thailand
fYear :
2013
fDate :
3-7 July 2013
Firstpage :
5087
Lastpage :
5090
Abstract :
Scatter signals in cone-beam computed tomography (CBCT) cause a significant problem that degrades image quality of reconstructed images, such as inaccuracy of CT numbers and cupping artifacts. In this paper, we will present an experiment-based scatter correction method by pre-processing projection images using a statistical model combined with experimental kernels. The convolution kernels are estimated by using different thickness of PMMA plates attached to a beam stop lead sheet such that the scatter signal values can be measure in the shadow area of the projection images caused by the lead sheet. The scatter signal values of different thickness levels can be measured in the shadow area of projection images caused by the lead sheet. Then, the projection images are convolved with the kernels that are derived from the actual measurement of scatter signals in PMMA plates. Finally, the primary signals can be estimated using the maximum likelihood expectation maximization method. Experimental results by using the proposed method show that the quality of the reconstruction images is significantly improved. The CT numbers become more accurate and the cupping artifact is reduced.
Keywords :
computerised tomography; expectation-maximisation algorithm; image reconstruction; medical image processing; statistical analysis; CBCT; PMMA plates; cone-beam computed tomography; cupping artifacts; experiment-based scatter correction method; experimental kernels; image quality; image reconstruction; maximum likelihood expectation maximization method; projection image preprocessing; scatter signals; statistical method; Computed tomography; Detectors; Image reconstruction; Kernel; Noise; Thickness measurement; X-ray imaging;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Engineering in Medicine and Biology Society (EMBC), 2013 35th Annual International Conference of the IEEE
Conference_Location :
Osaka
ISSN :
1557-170X
Type :
conf
DOI :
10.1109/EMBC.2013.6610692
Filename :
6610692
Link To Document :
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