Document Detail


The cause of the artifact in 4-slice helical computed tomography.
MedLine Citation:
PMID:  15305455     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The causes of the image artifacts in a 4-slice helical computed tomography have been discussed as follows: (1) changeover in pairs of data used in z interpolation, (2) sampling interval in z, and (3) the cone angle. This study analyzes the first two causes of the artifact and describes how the current algorithm [K. Taguchi and H. Aradate, Radiology 205P, 390 (1997); 205P, 618 (1997); Med. Phys. 25, 550-561 (1998); H. Hu, ibid. 26, 5-18 (1999); S. Schaller et al., IEEE Trans. Med. Imaging 19, 822-834 (2000); K. Taguchi, Ph.D. thesis, University of Tsukuba, 2002] solves the problem. An interpolated sinogram for a slice at the edge of a ball phantom shows discontinuity caused by the changeover. If we extend the streak artifact in the reconstructed image, it crosses the focus orbit at the corresponding projection angle. Applying z filtering can reduce such causes by its feathering effect and mixing data obtained by different cone angles; the best results are provided when z filtering is applied to densely sampled helical data.
Authors:
Katsuyuki Taguchi; Hiroshi Aradate; Yasuo Saito; Ilan Zmora; Kyung S Han; Michael D Silver
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Publication Detail:
Type:  Comparative Study; Evaluation Studies; Journal Article; Validation Studies    
Journal Detail:
Title:  Medical physics     Volume:  31     ISSN:  0094-2405     ISO Abbreviation:  Med Phys     Publication Date:  2004 Jul 
Date Detail:
Created Date:  2004-08-12     Completed Date:  2005-01-11     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0425746     Medline TA:  Med Phys     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2033-7     Citation Subset:  IM    
Affiliation:
CT Systems Development Department, Toshiba Medical Systems Corporation, 1385 Shimoishigami, Otawara, Tochigi 324-8550 Japan. ktaguchi@aol.com
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MeSH Terms
Descriptor/Qualifier:
Algorithms*
Anatomy, Cross-Sectional / methods*
Artifacts*
Imaging, Three-Dimensional / methods*
Radiographic Image Enhancement / methods*
Radiographic Image Interpretation, Computer-Assisted / methods*
Reproducibility of Results
Sensitivity and Specificity
Tomography, Spiral Computed / methods*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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