Investigation of the use of photon counting X-ray detectors with energy discrimination capability for material decomposition in micro-computed tomography

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

Abstract

Recently developed solid-state detectors combined with high-speed ASICs that allow individual pixel pulse processing may prove useful as detectors for small animal micro-computed tomography. One appealing feature of these photoncounting x-ray detectors (PCXDs) is their ability to discriminate between photons with different energies and count them in a small number (2-5) of energy windows. The data in these energy windows may be thought of as arising from multiple simultaneous x-ray beams with individual energy spectra, and could thus potentially be used to perform material composition analysis. The goal of this paper was to investigate the potential advantages of PCXDs with multiple energy window counting capability as compared to traditional integrating detectors combined with acquisition of images using x-ray beams with 2 different kVps. For the PCXDs, we investigated 3 potential sources of crosstalk: scatter in the object and detector, limited energy resolution, and pulse piluep. Using Monte Carlo simulations, we showed that scatter in the object and detector results in relatively little crosstalk between the data in the energy windows. To study the effects of energy resolution and pulse-pileup, we performed simulations evaluating the accuracy and precision of basis decomposition using a detector with 2 or 5 energy windows and a single kVp compared to an dual kVp acquisitions with an integrating detector. We found that, for noisy data, the precision of estimating the thickness of two basis materials for a range of material compositions was better for the single kVp multiple energy window acquisitions compared to the dual kVp acquisitions with an integrating detector. The advantage of the multi-window acquisition was somewhat reduced when the energy resolution was reduced to 10 keV and when pulse pileup was included, but standard deviations of the estimated thicknesses remained better by more than a factor of 2.

Original languageEnglish (US)
Title of host publicationMedical Imaging 2007
Subtitle of host publicationPhysics of Medical Imaging
PublisherSPIE
EditionPART 1
ISBN (Print)081946628X, 9780819466280
DOIs
StatePublished - Jan 1 2007
EventMedical Imaging 2007: Physics of Medical Imaging - San Diego, CA, United States
Duration: Feb 18 2007Feb 22 2007

Publication series

NameProgress in Biomedical Optics and Imaging - Proceedings of SPIE
NumberPART 1
Volume6510
ISSN (Print)1605-7422

Other

OtherMedical Imaging 2007: Physics of Medical Imaging
CountryUnited States
CitySan Diego, CA
Period2/18/072/22/07

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ASJC Scopus subject areas

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

Cite this

Frey, E. C., Wang, X., Du, Y., Taguchi, K., Xu, J., & Tsui, B. M. W. (2007). Investigation of the use of photon counting X-ray detectors with energy discrimination capability for material decomposition in micro-computed tomography. In Medical Imaging 2007: Physics of Medical Imaging (PART 1 ed.). [65100A] (Progress in Biomedical Optics and Imaging - Proceedings of SPIE; Vol. 6510, No. PART 1). SPIE. https://doi.org/10.1117/12.711711