| Preliminary study on helical CT algorithms for patient motion estimation and compensation. | |
| | |
MedLine Citation:
|
PMID: 18215824 Owner: NLM Status: In-Data-Review |
Abstract/OtherAbstract:
|
Helical computed tomography (helical/spiral CT) has replaced conventional CT in many clinical applications. In current helical CT, a patient is assumed to be rigid and motionless during scanning and planar projection sets are produced from raw data via longitudinal interpolation. However, rigid patient: motion is a problem in some cases (such as in the skull base and temporal bone imaging). Motion artifacts thus generated in reconstructed images can prevent accurate diagnosis. Modeling a uniform translational movement, the authors address how patient motion is ascertained and how it may be compensated. First, mismatch between adjacent fan-beam projections of the same orientation is determined via classical correlation, which is approximately proportional to the patient displacement projected onto an axis orthogonal to the central ray of the involved fan-beam. Then, the patient motion vector (the patient displacement per gantry rotation) is estimated from its projections using a least-square-root method. To suppress motion artifacts, adaptive interpolation algorithms are developed that synthesize full-scan and half-scan planar projection data sets, respectively. In the adaptive scheme, the interpolation is performed along inclined paths dependent upon the patient motion vector. The simulation results show that the patient motion vector can be accurately and reliably estimated using the authors' correlation and least-square-root algorithm, patient motion artifacts can be effectively suppressed via adaptive interpolation, and adaptive half-scan interpolation is advantageous compared with its full-scan counterpart in terms of high contrast image resolution. |
| | |
Authors:
|
G Wang; M W Vannier |
Related Documents
:
|
20351654 - Using standard nonenhanced axial scans for cerebral ct angiography bone elimination: fe... 12130444 - Helical ct of the local spread of carcinoma of the gallbladder: evaluation according to... 20858824 - Stone-targeted dual-energy ct: a new diagnostic approach to urinary calculosis. 10470884 - Dynamic contrast-enhanced mr imaging and dual-phase helical ct in the preoperative asse... 15932564 - Pre-operative assessment of extramural invasion and sphincteral involvement in rectal c... 21718324 - Pet in vasculitis. |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: IEEE transactions on medical imaging Volume: 14 ISSN: 0278-0062 ISO Abbreviation: IEEE Trans Med Imaging Publication Date: 1995 |
Date Detail:
|
Created Date: 2008-01-24 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 8310780 Medline TA: IEEE Trans Med Imaging Country: United States |
Other Details:
|
Languages: eng Pagination: 205-11 Citation Subset: - |
Affiliation:
|
Mallinckrodt Inst. of Radiol., Washington Univ. Sch. of Med., St. Louis, MO. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Reconstruction from projections under time-frequency constraints.
Next Document: Object recognition in brain CT-scans: knowledge-based fusion of data from multiple feature extractor...