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European Radiology

, Volume 29, Issue 12, pp 6794–6804 | Cite as

Local clinical diagnostic reference levels for chest and abdomen CT examinations in adults as a function of body mass index and clinical indication: a prospective multicenter study

  • Hugues BratEmail author
  • Federica Zanca
  • Stéphane Montandon
  • Damien Racine
  • Benoit Rizk
  • Eric Meicher
  • Dominique Fournier
Physics

Abstract

Objectives

To compare institutional dose levels based on clinical indication and BMI class to anatomy-based national DRLs (NDRLs) in chest and abdomen CT examinations and to assess local clinical diagnostic reference levels (LCDRLs).

Methods

From February 2017 to June 2018, after protocol optimization according to clinical indication and body mass index (BMI) class (< 25; ≥ 25), 5310 abdomen and 1058 chest CT series were collected from 5 CT scanners in a Swiss multicenter group. Clinical indication–based institutional dose levels were compared to the Swiss anatomy-based NDRLs. Statistical significance was assessed (p < 0.05). LCDRLs were calculated as the third quartile of the median dose values for each CT scanner.

Results

For chest examinations, dose metrics based on clinical indication were always below P75 NDRL for CTDIvol (range 3.9–6.4 vs. 7.0 mGy) and DLP (164.0–211.2 vs. 250 mGycm) in all BMI classes except for DLP in BMI ≥ 25 (248.8–255.4 vs. 250.0 mGycm). For abdomen examinations, they were significantly lower or not different than P50 NDRLs for all BMI classes (3.8–9.0 vs. 10.0 mGy and 192.9–446.8 vs. 470mGycm). The estimated LCDRLs show a drop in CTDIvol (21% for chest and 32% for abdomen, on average) with respect to current DRLs. When considering BMI stratification, the largest LCDRL difference within the same clinical indication is for renal tumor (4.6 mGy for BMI < 25 vs. 10.0 mGy for BMI ≥ 25; − 117%).

Conclusion

The results suggest the necessity of estimating clinical indication–based DRLs, especially for abdomen examinations. Stratifying per BMI class allows further optimization of the CT doses.

Key Points

• Our data show that clinical indication–based DRLs might be more appropriate than anatomy-based DRLs and might help in reducing large variations in dose levels for the same type of examinations.

• Stratifying the data per patient-size subgroups (non-overweight, overweight) allows a better optimization of CT doses and therefore the possibility to set LCDRLs based on BMI class.

• Institutions who are fostering continuous dose optimization and LDRLs should consider defining protocols based on clinical indication and BMI group, to achieve ALARA.

Keywords

Multidetector computed tomography Radiometry Health care Clinical protocols 

Abbreviations

AD

Achievable doses

BMI

Body mass index

CDRL

Clinical diagnostic reference level

CHO

Channelized Hotelling observer

CT

Computed tomography

CTDI

Computed tomography dose index

DLP

Dose length product

DRL

Diagnostic reference level

Dw

Water-equivalent diameter

EUCLID

European study on clinical DRLs

G3R

Groupe 3R

ICRP

International Commission on Radiological Protection

LCDRL

Local clinical diagnostic reference level

LDRL

Local diagnostic reference level

MDCT

Multidetector CT scanner

NDRL

National diagnostic reference level

Notes

Acknowledgments

The authors would like to thank Christophe Dias, Camille La Fay, Hugo Pasquier, and Dr Michael Seidenbusch for their valuable contribution to this article.

Funding

The authors state that this work has not received any funding.

Compliance with ethical standards

Guarantor

The scientific guarantor of this publication is Dr. Dominique Fournier.

Conflict of interest

The authors of this manuscript declare relationships with the following companies:

Federica Zanca was a former employee of GE Healthcare.

Stephane Montandon is a Philips employee.

Statistics and biometry

No complex statistical methods were necessary for this paper.

Informed consent

A written informed consent is submitted to every patient upon admission in Groupe 3r stating, among others, possible use of anonymized patient data for research purposes. The patient is free to oppose this use and listed as such. Specific written informed consent was therefore waived by the Institutional Review Board.

Ethical approval

Institutional Review Board approval was obtained.

Methodology

• Prospective

• Observational

• Multicenter study

Supplementary material

330_2019_6257_MOESM1_ESM.docx (16 kb)
Appendix . Dates of the study phases. (DOCX 16 kb)

References

  1. 1.
    International Commission on Radiological Protection (1996) ICRP publication 73: radiological protection and safety in medicine. Ann ICRP 26(2)Google Scholar
  2. 2.
    Vañó E, Miller DL, Martin CJ et al ICRP publication 135: diagnostic reference levels in medical imaging. Ann ICRP 46(1) 1–144Google Scholar
  3. 3.
    Kanal KM, Butler PF, Sengupta D, Bhargavan-Chatfield M, Coombs LP, Morin RL (2017) U.S. diagnostic reference levels and achievable doses for 10 adult CT examinations. Radiology 284(1):120–133CrossRefGoogle Scholar
  4. 4.
    Treier R, Aroua A, Verdun FR, Samara E, Stuessi A, Trueb PR (2010) Patient doses in CT examinations in Switzerland: implementation of national diagnostic reference levels. Radiat Prot Dosimetry 142(2–4):244–254CrossRefGoogle Scholar
  5. 5.
    Mabotuwana T, Lee MC, Cohen-Solal EV, Chang P (2014) Mapping institution-specific study descriptions to RadLex playbook entries. J Digit Imaging 273:321–330CrossRefGoogle Scholar
  6. 6.
    Racine D, Ba AH, Ott JG, Bochud FO, Verdun FR (2016) Objective assessment of low contrast detectability in computed tomography with channelized Hotelling observer. Phys Med 32(1):76–83CrossRefGoogle Scholar
  7. 7.
    European Commission (1999) European guidelines on quality criteria for computed tomography. European Commission, Brussels. Available via http://www.drs.dk/guidelines/ct/quality/index.htm. Accessed 10 September 2018
  8. 8.
    Federal Office of Public Health (2018) Directive R-06-06 Niveaux de référence diagnostiques en tomodensitométrie. Available via https://www.bag.admin.ch/dam/bag/fr/dokumente/str/std/bag-wegleitungen/2018-06-15-r-06-06.pdf. Accessed 13 October 2018
  9. 9.
    Foley SJ, McEntee MF, Rainford LA (2012) Establishment of CT diagnostic reference levels in Ireland. Br J Radiol 85(1018):1390–1397CrossRefGoogle Scholar
  10. 10.
    Fukushima Y, Tsushima Y, Takei H, Taketomi-Takahashi A, Otake H, Endo K (2012) Diagnostic reference level of computed tomography (CT) in Japan. Radiat Prot Dosimetry 151(1):51–57CrossRefGoogle Scholar
  11. 11.
    Kim MC, Han DK, Nam YC, Kim YM, Yoon J (2014) Patient dose for computed tomography examination: dose reference levels and effective doses based on a national survey of 2013 in Korea. Radiat Prot Dosimetry 164(3):383–391CrossRefGoogle Scholar
  12. 12.
    Palorini F, Origgi D, Granata C, Matranga D, Salerno S (2014) Adult exposures from MDCT including multiphase studies: first Italian nationwide survey. Eur Radiol 24(2):469–483CrossRefGoogle Scholar
  13. 13.
    McCollough C, Branham T, Herlihy V et al (2011) Diagnostic reference levels from the ACR CT accreditation program. J Am Coll Radiol 8(11):795–803CrossRefGoogle Scholar
  14. 14.
    Najafi M, Deevband MR, Ahmadi M, Kardan MR (2015) Establishment of diagnostic reference levels for common multi-detector computed tomography examinations in Iran. Australas Phys Eng Sci Med 38(4):603–609CrossRefGoogle Scholar
  15. 15.
    Santos J, Foley S, Paulo G, McEntee MF, Rainford L (2014) The establishment of computed tomography diagnostic reference levels in Portugal. Radiat Prot Dosimetry 158(3):307–317CrossRefGoogle Scholar
  16. 16.
    Tsapaki V, Aldrich JE, Sharma R et al (2006) Dose reduction in CT while maintaining diagnostic confidence: diagnostic reference levels at routine head, chest, and abdominal CT--IAEA-coordinated research project. Radiology 240(3):828–834CrossRefGoogle Scholar
  17. 17.
    Wall BF (2005) Implementation of DRLs in the UK. Radiat Prot Dosimetry 114(1–3):183–187CrossRefGoogle Scholar
  18. 18.
    Appel E, Kröpil P, Bethge OT, Aissa J, Thomas C, Antoch G, Boos J (2018) Quality assurance in CT: implementation of the updated national diagnostic reference levels using an automated CT dose monitoring system. Clin Radiol 73(7):677.e13–677.e20.  https://doi.org/10.1016/j.crad.2018.02.012 CrossRefGoogle Scholar
  19. 19.
    Roch P, Célier D, Dessaud C, Etard C (2018) Using diagnostic reference levels to evaluate the improvement of patient dose optimisation and the influence of recent technologies in radiography and computed tomography. Eur J Radiol 98:68–74.  https://doi.org/10.1016/j.ejrad.2017.11.002 CrossRefPubMedGoogle Scholar
  20. 20.
    Ghetti C, Ortenzia O, Palleri F, Sireus M (2017) Definition of local diagnostic reference levels in a radiology department using a dose tracking software. Radiat Prot Dosimetry 175(1):38–45PubMedGoogle Scholar
  21. 21.
    Liang CR, Chen PXH, Kapur J, Ong MKL, Quek ST, Kapur SC (2017) Establishment of institutional diagnostic reference level for computed tomography with automated dose-tracking software. J Med Radiat Sci 64(2):82–89CrossRefGoogle Scholar
  22. 22.
    MacGregor K, Li I, Dowdell T, Gray BG (2015) Identifying institutional diagnostic reference levels for CT with radiation dose index monitoring software. Radiology 276(2):507–517CrossRefGoogle Scholar
  23. 23.
    Pyfferoen L, Mulkens TH, Zanca F, De Bondt T, Parizel PM, Casselman JW (2017) Benchmarking adult CT-dose levels to regional and national references using a dose-tracking software: a multicentre experience. Insights Imaging 8(5):513–521CrossRefGoogle Scholar
  24. 24.
    Tonkopi E, Duffy S, Abdolell M, Manos D (2017) Diagnostic reference levels and monitoring practice can help reduce patient dose from CT examinations. AJR Am J Roentgenol 208(5):1073–1081CrossRefGoogle Scholar
  25. 25.
    Lajunen A (2015) Indication-based diagnostic reference levels for adult CT-examinations in Finland. Radiat Prot Dosimetry 165(1–4):95–97CrossRefGoogle Scholar
  26. 26.
    Klosterkemper Y, Appel E, Thomas C et al (2018) Tailoring CT dose to patient size: implementation of the updated 2017 ACR size-specific diagnostic reference levels. Acad Radiol.  https://doi.org/10.1016/j.acra.2018.03.005
  27. 27.
    Boere H, Eijsvoogel NG, Sailer AM et al (2018) Implementation of size-dependent local diagnostic reference levels for CT angiography. AJR Am J Roentgenol 210(5):W226–W233.  https://doi.org/10.2214/AJR.17.18566 CrossRefPubMedGoogle Scholar

Copyright information

© European Society of Radiology 2019

Authors and Affiliations

  1. 1.Institut de Radiologie de Sion, Groupe 3RSionSwitzerland
  2. 2.GE HealthcareBucFrance
  3. 3.Palindromo ConsultingLeuvenBelgium
  4. 4.Philips HealthcareGlandSwitzerland
  5. 5.Institute of Radiation Physics (IRA)Lausanne University Hospital and University of LausanneLausanneSwitzerland

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