Accurate determination of the shape and location of metal objects in X-ray computed tomography

Jing Wang, Lei Xing

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

The presence of metals in patient causes streaking artifacts in X-ray CT and has long been recognized as a problem that limits various applications of CT imaging. Accurate localization of metals in CT images is a critical step for metal artifacts reduction in CT imaging and many practical applications of CT images. The purpose of this work is to develop a method of auto-determination of the shape and location of metallic object(s) in the image space. The proposed method is based on the fact that when a metal object is present in a patient, a CT image can be divided into two prominent components: high density metal and low density normal tissues. This prior knowledge is incorporated into an objective function as the regularization term whose role is to encourage the solution to take a form of two intensity levels. The function is minimized by using a Gauss-Seidel iterative algorithm. A computer simulation study and four experimental studies are performed to evaluate the proposed approach. Both simulation and experimental studies show that the presented algorithm works well even in the presence of complicated shaped metal objects. For a hexagonally shaped metal embedded in a water phantom, for example, it is found that the accuracy of metal reconstruction is within sub-millimeter. The algorithm is of practical importance for imaging patients with implanted metals.

Original languageEnglish (US)
Title of host publicationProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume7622
EditionPART 3
DOIs
StatePublished - 2010
EventMedical Imaging 2010: Physics of Medical Imaging - San Diego, CA, United States
Duration: Feb 15 2010Feb 18 2010

Other

OtherMedical Imaging 2010: Physics of Medical Imaging
CountryUnited States
CitySan Diego, CA
Period2/15/102/18/10

Fingerprint

X Ray Computed Tomography
Tomography
tomography
Metals
X rays
metals
x rays
Imaging techniques
Artifacts
artifacts
Computer Simulation
computerized simulation
Tissue
Water
causes
Computer simulation

Keywords

  • Gradient-controlled penalty
  • Iterative image reconstruction
  • Metal artifacts reduction
  • Metal localization
  • X-ray computed tomography

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Radiology Nuclear Medicine and imaging

Cite this

Wang, J., & Xing, L. (2010). Accurate determination of the shape and location of metal objects in X-ray computed tomography. In Progress in Biomedical Optics and Imaging - Proceedings of SPIE (PART 3 ed., Vol. 7622). [76225A] https://doi.org/10.1117/12.844294

Accurate determination of the shape and location of metal objects in X-ray computed tomography. / Wang, Jing; Xing, Lei.

Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7622 PART 3. ed. 2010. 76225A.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Wang, J & Xing, L 2010, Accurate determination of the shape and location of metal objects in X-ray computed tomography. in Progress in Biomedical Optics and Imaging - Proceedings of SPIE. PART 3 edn, vol. 7622, 76225A, Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, United States, 2/15/10. https://doi.org/10.1117/12.844294
Wang J, Xing L. Accurate determination of the shape and location of metal objects in X-ray computed tomography. In Progress in Biomedical Optics and Imaging - Proceedings of SPIE. PART 3 ed. Vol. 7622. 2010. 76225A https://doi.org/10.1117/12.844294
Wang, Jing ; Xing, Lei. / Accurate determination of the shape and location of metal objects in X-ray computed tomography. Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7622 PART 3. ed. 2010.
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