Image-based dual energy CT improvements using gram-schmidt method

Kyung Kook Park, Metin Akay, William Pavlicek, Thomas Boltz, Robert Paden, Amy Hara

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

1 Citation (Scopus)

Abstract

Dual energy x-ray CT images are computed using either image or projection data. The latter is thought to be preferable for two-material decomposition. Nonetheless, using effective energies of polychromatic x-ray beams at separated kVp values, material decomposition and pseudo-monochromatic reconstruction can be performed from reconstructed images. This image-based approach generates added noise which should benefit from applying processing for noise reduction. A set of material attenuation information so produced defines a vector space, which represents the true material property but is predefined from mass attenuation coefficients of major body-composite materials. We assumed 53keV and 72keV x-ray effective energies for 80kVp and 140kVp dual energy CT. The Gram-Schmidt process was applied to remove noise orthogonal to the vector spaces of the body-composite materials. Two-material decomposition was performed, and monochromatic and density images were reconstructed. Evaluations of image noise, Hounsfield unit accuracy, and resolution with a phantom, as well as with abdominal images, demonstrates improved CNR and SNR without loss of detail. This method of noise suppression also produced high quality density maps of two basis materials. Since dual energy CT currently uses slightly above average radiation dose, this method has the potential for lowering dose in addition to improving image quality.

Original languageEnglish (US)
Title of host publicationProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume7258
DOIs
StatePublished - 2009
EventMedical Imaging 2009: Physics of Medical Imaging - Lake Buena Vista, FL, United States
Duration: Feb 9 2009Feb 12 2009

Other

OtherMedical Imaging 2009: Physics of Medical Imaging
CountryUnited States
CityLake Buena Vista, FL
Period2/9/092/12/09

Fingerprint

Schmidt method
Noise
X-Rays
Vector spaces
Decomposition
X rays
vector spaces
energy
decomposition
Composite materials
Noise abatement
Acoustic noise
Image quality
Dosimetry
Radiation
Materials properties
dosage
x rays
composite materials
attenuation coefficients

Keywords

  • Computerized tomography
  • DECT
  • Density imaging
  • Dual-energy CT
  • Image enhancement

ASJC Scopus subject areas

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

Cite this

Park, K. K., Akay, M., Pavlicek, W., Boltz, T., Paden, R., & Hara, A. (2009). Image-based dual energy CT improvements using gram-schmidt method. In Progress in Biomedical Optics and Imaging - Proceedings of SPIE (Vol. 7258). [72583S] https://doi.org/10.1117/12.811122

Image-based dual energy CT improvements using gram-schmidt method. / Park, Kyung Kook; Akay, Metin; Pavlicek, William; Boltz, Thomas; Paden, Robert; Hara, Amy.

Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7258 2009. 72583S.

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

Park, KK, Akay, M, Pavlicek, W, Boltz, T, Paden, R & Hara, A 2009, Image-based dual energy CT improvements using gram-schmidt method. in Progress in Biomedical Optics and Imaging - Proceedings of SPIE. vol. 7258, 72583S, Medical Imaging 2009: Physics of Medical Imaging, Lake Buena Vista, FL, United States, 2/9/09. https://doi.org/10.1117/12.811122
Park KK, Akay M, Pavlicek W, Boltz T, Paden R, Hara A. Image-based dual energy CT improvements using gram-schmidt method. In Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7258. 2009. 72583S https://doi.org/10.1117/12.811122
Park, Kyung Kook ; Akay, Metin ; Pavlicek, William ; Boltz, Thomas ; Paden, Robert ; Hara, Amy. / Image-based dual energy CT improvements using gram-schmidt method. Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7258 2009.
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