Abstract
The calculation and verification of a CT number to density conversion table for a simulator-CT attachment known as Scanvision, which provides CT images for radiotherapy treatment planning, is presented. While the linear fit for CT-number-to-density is similar to most conventional doughnut gantry CT scanners, an offset of approximately 178 Hounsfield units was found for air using a polyethylene normalisation, and approximately 262 for air using air normalisation. The offset continues for other low-density samples. Results show that the simulator-CT reproducibly measures CT numbers. However a separate calibration line needs to be entered into the radiotherapy planning computer to ensure accurate CT-number-to-density conversion.
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Chapman, A., Butson, M., Quach, K. et al. Verification of CT number to density conversion for a simulator-CT attachment. Australas. Phys. Eng. Sci. Med. 25, 78–80 (2002). https://doi.org/10.1007/BF03178469
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DOI: https://doi.org/10.1007/BF03178469