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Quality control within the multicentre perfusion CT study of primary colorectal cancer (PROSPeCT): results of an iodine density phantom study

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Abstract

Objectives

To assess the cross-centre consistency of iodine enhancement, contrast-to-noise ratio and radiation dose in a multicentre perfusion CT trial of colorectal cancer.

Materials and methods

A cylindrical water phantom containing different iodine inserts was examined on seven CT models in 13 hospitals. The relationship between CT number (Hounsfield units, HU) and iodine concentration (milligrams per millilitre) was established and contrast-to-noise ratios (CNRs) calculated. Radiation doses (CTDIvol, DLP) were compared across all sites.

Results

There was a linear relationship between CT number and iodine density. Iodine enhancement varied by a factor of at most 1.10, and image noise by at most 1.5 across the study sites. At an iodine concentration of 1 mg ml−1 and 100 kV, CNRs ranged from 3.6 to 4.8 in the 220-mm phantom and from 1.4 to 1.9 in the 300-mm phantom. Doses varied by a factor of at most 2.4, but remained within study dose constraints. Iterative reconstruction algorithms did not alter iodine enhancement but resulted in reduced image noise by a factor of at most 2.2, allowing a potential dose decrease of at most 80 % compared to filtered back projection (FBP).

Conclusions

Quality control of CT performance across centres indicates that CNR values remain relatively consistent across all sites, giving acceptable image quality within the agreed dose constraints.

Key Points

Quality control is essential in a multicentre setting to enable CT quantification.

CNRs in a body-sized phantom had the recommended value of at least 1.5.

CTDIs and DLPs varied by factors of 1.8 and 2.4 respectively.

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References

  1. Miles KA, Young H, Chica SL, Esser PD (2007) Quantitative contrast-enhanced computed tomography: is there a need for system calibration? Eur Radiol 17:919–926

    Article  PubMed  Google Scholar 

  2. Driscoll B, Keller H, Jaffray D, Coolens C (2013) Development of a dynamic quality assurance testing protocol for multisite clinical trial DCE-CT accreditation. Med Phys 40:081906

    Article  CAS  PubMed  Google Scholar 

  3. Miles KA, Lee TY, Goh V et al (2012) Current status and guidelines for the assessment of tumour vascular support with dynamic contrast-enhanced computed tomography. Eur Radiol 22:1430–1441

    Article  CAS  PubMed  Google Scholar 

  4. Cagnon CH, Cody DD, McNitt-Gray MF, Seibert JA, Judy PF, Aberle DR (2006) Description and implementation of a quality control program in an imaging-based clinical trial. Acad Radiol 13:1431–1441

    Article  PubMed  Google Scholar 

  5. Information Services Division Scotland. Cancer Clinical Trials Service – PROSPeCT. http://www.isdscotland.org/Products-and-Services/Cancer-Clinical-Trials-Service/PROSPeCT.asp. Accessed 3 Oct 2013

  6. Institute of Physics and Engineering in Medicine (2005) Report 91. Recommended standards for the routine performance testing of diagnostic x-ray imaging systems. Chap. 12: computed tomography. IPEM, York

  7. Huda W, Magill D, He W (2011) CT effective dose per dose length product using ICRP 103 weighting factors. Med Phys 38:1261–1265

    Article  PubMed  Google Scholar 

  8. ImPACT CTDosimetry tool. Version 1.0.4. Available via http://www.impactscan.org/ctdosimetry.htm. Accessed 3 Oct 2013

  9. Shrimpton PC, Hillier MC, Lewis MA, Dunn M (2006) National survey of doses from CT in the UK: 2003. Br J Radiol 79:968–980

    Article  CAS  PubMed  Google Scholar 

  10. Miles KA (2003) Perfusion CT for the assessment of tumour vascularity: which protocol? Br J Radiol 76:S36–S42

    Article  PubMed  Google Scholar 

  11. Huda W, Scalzetti EM, Levin G (2000) Technique factors and image quality as functions of patient weight at abdominal CT. Radiology 217:430–435

    Article  CAS  PubMed  Google Scholar 

  12. Yu L, Li H, Fletcher JG, McCollough CH (2010) Automatic selection of tube potential for radiation dose reduction in CT: a general strategy. Med Phys 37:234–243

    Article  PubMed  Google Scholar 

  13. Löve A, Olsson ML, Siemund R, Stålhammar F, Björkman-Burtscher IM, Söderberg M (2013) Six iterative reconstruction algorithms in brain CT: a phantom study on image quality at different radiation dose levels. Br J Radiol 86:20130388

    Article  PubMed  Google Scholar 

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Acknowledgments

We would like to acknowledge Nick Keat (Imanova Ltd) for writing the IDL image analysis modules and Paul Woodburn (GSTT) for preparing the iodine solutions.

We would like to acknowledge the following for their contribution to the PROSPeCT study:

Principal investigators: M Betts, I Britton, D Breen, J Brush, P Correa, N Dodds, C Grierson, N Griffin, S Gourtsoyianni, J Hampton, A Higginson, A Lowe, R Mannion, C Oliver, A Slater, M Strugnell, D Tolan, R Vinayagam, I Zealley

Site radiographers & research staff: (in alphabetical order):

D Barrie, G Cattini, N Cowan, M Dodds, S Dundas, N Gibbons, A Green, M Harris, G Haley, L Houston, K Jones, L Jones, C Marsh, E Ngandwe, B Pharoah, V Ritchie, C Roe, R Smith, D Tew, K Wallace, A Williams, P Woodburn, N Wragg

Trial management group, steering committee, data monitoring committee, and advisors (in alphabetical order):

D Altman, C Bartram, R Glynne-Jones, A Groves, A Hackshaw, S Halligan, P Hoskin, S Mallett, D Miles, K Miles, A Rockall, M Rodriguez-Justo, SA Taylor

The scientific guarantor of this publication is Professor Vicky Goh. The authors of this manuscript declare relationships with the following companies: Vicky Goh: Research Agreement Siemens Healthcare, GE Healthcare. Other authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. This study has received funding from the UK National Institute of Health Research (NIHR) HTA programme: Funding NIHR HTA 09/22/49. Dr Susan Mallett (Oxford) is providing statistical expertise for the trial. No complex statistical methods were necessary for this paper. Institutional review board approval was obtained. Methodology: prospective, experimental: phantom study, multicentre study.

The authors also acknowledge financial support from the Department of Health via the National Institute for Health Research Comprehensive Biomedical Research Centre award to Guy's & St Thomas' NHS Foundation Trust in partnership with King's College London and King's College Hospital NHS Foundation Trust; and from the King's College London/University College London Comprehensive Cancer Imaging Centre funded by Cancer Research UK and Engineering and Physical Sciences Research Council in association with the Medical Research Council and Department of Health.

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Correspondence to Vicky Goh.

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Lewis, M., Goh, V., Beggs, S. et al. Quality control within the multicentre perfusion CT study of primary colorectal cancer (PROSPeCT): results of an iodine density phantom study. Eur Radiol 24, 2309–2318 (2014). https://doi.org/10.1007/s00330-014-3258-y

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  • DOI: https://doi.org/10.1007/s00330-014-3258-y

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