Dataset Information

VOXSI: A voxelized single- and dual-energy CT scenario generator for quantitative imaging.

ABSTRACT:

Background and purpose

Dedicated CT simulation models have the potential to investigate several acquisition, reconstruction, or post-processing parameters without giving any radiation dose to patients. A software program was developed for the simulation and the analysis of single-energy and dual-energy CT images. Simulation and analysis functionalities of the software are described.

Materials and methods

In the software, named VOXSI (VOXelized CT SImulator), the X-ray source, user specified simulation geometry, CT setup and the detector energy response can be varied. CT image reconstructions can be performed with an implementation of the ASTRA toolbox. In the DECT post processing toolkit, GUI tools are provided to calculate effective atomic number, relative electron density, pseudo-monoenergetic images, and material map images. Quantitative CT number validation, based on a RMI 467 tissue characterization phantom model, was performed between experimental and simulated CT scans at three different X-ray tube potentials (80, 120, and 140?kVp) with a third generation CT scanner.

Results

Overall, a good agreement was found for the mean CT numbers of the RMI 467 inserts. For all energies, the maximum difference in CT numbers between experimental and simulated data was below 17?HU for the soft tissues and below 48?HU for the osseous tissues.

Conclusion

The software's simulation algorithm showed a good agreement between the CT measurements and CT simulations of the RMI 467 phantom at different energies. The capabilities of the software are demonstrated by an elaborated dual-energy CT research example.

SUBMITTER: van der Heyden B

PROVIDER: S-EPMC7807865 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Publications

<i>VOXSI:</i> A voxelized single- and dual-energy CT scenario generator for quantitative imaging.

van der Heyden Brent B Schyns Lotte E J R LEJR Podesta Mark M Vaniqui Ana A Almeida Isabel P IP Landry Guillaume G Verhaegen Frank F

Physics and imaging in radiation oncology 20180401

<h4>Background and purpose</h4>Dedicated CT simulation models have the potential to investigate several acquisition, reconstruction, or post-processing parameters without giving any radiation dose to patients. A software program was developed for the simulation and the analysis of single-energy and dual-energy CT images. Simulation and analysis functionalities of the software are described.<h4>Materials and methods</h4>In the software, named <i>VOXSI</i> (VOXelized CT SImulator), the X-ray sourc ...[more]

PMID: 33458388

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