Achieving accurate radiochromic optical-CT imaging when using a polychromatic light source.


Journal Article

Optical-CT performed with a broad spectrum light source can lead to inaccurate reconstructed attenuation coefficients (and hence dose) due to 'spectral warping' as the beam passes through the dosimeter. Some wavelengths will be attenuated more strongly than others depending on the absorption spectrum of the radiochromic dosimeter. A simulation was run to characterize the error introduced by the spectrum warping phenomena. Simulations of a typical dosimeter and delivered dose (6cm diameter, 2 Gy irradiation) showed reconstructed attenuation coefficients can be in error by >12% when compared to those obtained from a monochromatic scan. A method to correct for these errors is presented and preliminary data suggests that with the correction, polychromatic imaging can yield imaging results equal in accuracy to those of monochromatic imaging. The advantage is that polychromatic imaging may be less sensitive to prominent schlerring artefacts that are often observed in telecentric optical-CT scanning systems with tight bandwidth filters applied.

Full Text

Duke Authors

Cited Authors

  • Thomas, A; Pierquet, M; Oldham, M

Published Date

  • 2010

Published In

Volume / Issue

  • 250 / 12045

Start / End Page

  • 210 - 214

PubMed ID

  • 21289868

Pubmed Central ID

  • 21289868

International Standard Serial Number (ISSN)

  • 1742-6588

Digital Object Identifier (DOI)

  • 10.1088/1742-6596/250/1/012045


  • eng

Conference Location

  • England