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Published in: Insights into Imaging 5/2013

Open Access 01-10-2013 | Original Article

A questionnaire survey reviewing radiologists’ and clinical specialist radiographers’ knowledge of CT exposure parameters

Authors: S. J. Foley, M. G. Evanoff, L. A. Rainford

Published in: Insights into Imaging | Issue 5/2013

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Abstract

Objective

To review knowledge of computed tomography (CT) parameters and their influence on patient dose and image quality amongst a cohort of clinical specialist radiographers (CSRs) and examining radiologists.

Methods

A questionnaire survey was devised and distributed to a cohort of 65 examining radiologists attending the American Board of Radiology exam in Kentucky in November 2011. The questionnaire was later distributed by post to a matching cohort of Irish CT CSRs. Each questionnaire contained 40 questions concerning CT parameters and their influence on both patient dose and image quality.

Results

A response rate of 22 % (radiologists) and 32 % (CSRs) was achieved. No difference in mean scores was detected between either group (27.8 ± 4 vs 28.1 ± 4, P = 0.87) although large ranges were noted (18–36). Considerable variations in understanding of CT parameters was identified, especially regarding operation of automatic exposure control and the influence of kilovoltage and tube current on patient dose and image quality. Radiologists were unaware of recommended diagnostic reference levels. Both cohorts were concerned regarding CT doses in their departments.

Conclusions

CT parameters were well understood by both groups. However, a number of deficiencies were noted which may have a considerable impact on patient doses and limit the potential for optimisation in clinical practice.

Key points

CT users must adapt parameters to optimise patient dose and image quality.
The influence of some parameters is not well understood.
A need for ongoing education in dose optimisation is identified.
Appendix
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Literature
1.
go back to reference UNSCEAR (2008) Sources and effects of ionizing radiation. Report to the general assesmbly with scientific annexes. United Nations, New York UNSCEAR (2008) Sources and effects of ionizing radiation. Report to the general assesmbly with scientific annexes. United Nations, New York
2.
go back to reference NCRP (2009) Ionizing radiation exposure of the population of the United States. National Council on Radiation Protection and Measurement, Bethesda NCRP (2009) Ionizing radiation exposure of the population of the United States. National Council on Radiation Protection and Measurement, Bethesda
3.
go back to reference Brenner DJ, Hall EJ (2007) Computed tomography—an increasing source of radiation exposure. N Engl J Med 357:2277–2284PubMedCrossRef Brenner DJ, Hall EJ (2007) Computed tomography—an increasing source of radiation exposure. N Engl J Med 357:2277–2284PubMedCrossRef
4.
go back to reference Pearce MS et al (2012) Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study. Lancet 380:499–505PubMedPubMedCentralCrossRef Pearce MS et al (2012) Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study. Lancet 380:499–505PubMedPubMedCentralCrossRef
5.
go back to reference Bogdanich W (2010) After stroke scans, patients face serious health risks. In: The New York Times, New York Bogdanich W (2010) After stroke scans, patients face serious health risks. In: The New York Times, New York
6.
go back to reference Zarembo A (2009) Cedars-Sinai investigated for significant overdoses of 206 patients. In: Los Angeles Times, Los Angeles Zarembo A (2009) Cedars-Sinai investigated for significant overdoses of 206 patients. In: Los Angeles Times, Los Angeles
7.
go back to reference USDHHS (2005) Report on Carcinogens, Eleventh Edition. National Toxicology Program, US Department of Health and Human Sciences, Public Health Service, National Toxicology Program, Washington USDHHS (2005) Report on Carcinogens, Eleventh Edition. National Toxicology Program, US Department of Health and Human Sciences, Public Health Service, National Toxicology Program, Washington
8.
go back to reference Valentin J; International Commission on Radiation Protection (2007) Managing patient dose in multi-detector computed tomography (MDCT). Publication 102. Ann ICRP 37:1–79 Valentin J; International Commission on Radiation Protection (2007) Managing patient dose in multi-detector computed tomography (MDCT). Publication 102. Ann ICRP 37:1–79
9.
go back to reference Amis ES Jr et al (2007) American College of Radiology White Paper on radiation dose in medicine. J Am Coll Radiol 4:272–284PubMedCrossRef Amis ES Jr et al (2007) American College of Radiology White Paper on radiation dose in medicine. J Am Coll Radiol 4:272–284PubMedCrossRef
11.
go back to reference Hollingsworth C et al (2003) Helical CT of the body: a survey of techniques used for pediatric patients. AJR Am J Roentgenol 180:401–406PubMedCrossRef Hollingsworth C et al (2003) Helical CT of the body: a survey of techniques used for pediatric patients. AJR Am J Roentgenol 180:401–406PubMedCrossRef
12.
go back to reference Rizzo S et al (2006) Comparison of angular and combined automatic tube current modulation techniques with constant tube current CT of the abdomen and pelvis. AJR Am J Roentgenol 186:673–679PubMedCrossRef Rizzo S et al (2006) Comparison of angular and combined automatic tube current modulation techniques with constant tube current CT of the abdomen and pelvis. AJR Am J Roentgenol 186:673–679PubMedCrossRef
13.
go back to reference Yu L et al (2010) Automatic selection of tube potential for radiation dose reduction in CT: a general strategy. Med Phys 37:234–243PubMedCrossRef Yu L et al (2010) Automatic selection of tube potential for radiation dose reduction in CT: a general strategy. Med Phys 37:234–243PubMedCrossRef
14.
go back to reference Matsubara K et al (2009) Misoperation of CT automatic tube current modulation systems with inappropriate patient centering: phantom studies. AJR Am J Roentgenol 192:862–865PubMedCrossRef Matsubara K et al (2009) Misoperation of CT automatic tube current modulation systems with inappropriate patient centering: phantom studies. AJR Am J Roentgenol 192:862–865PubMedCrossRef
15.
go back to reference Gudjonsdottir J et al (2009) Efficient use of automatic exposure control systems in computed tomography requires correct patient positioning. Acta Radiol 50:1035–1041PubMedCrossRef Gudjonsdottir J et al (2009) Efficient use of automatic exposure control systems in computed tomography requires correct patient positioning. Acta Radiol 50:1035–1041PubMedCrossRef
16.
go back to reference HSE (2010) Population dose from CT Scanning: 2009. Health Services Executive, Dublin HSE (2010) Population dose from CT Scanning: 2009. Health Services Executive, Dublin
17.
go back to reference Edwards P et al (2007) Methods to increase response rates to postal questionnaires. Cochrane Database Syst Rev 18:MR000008 Edwards P et al (2007) Methods to increase response rates to postal questionnaires. Cochrane Database Syst Rev 18:MR000008
18.
go back to reference Shih T-H, Fan X (2009) Comparing response rates in e-mail and paper surveys: a meta-analysis. Educ Res Rev 4:26–40CrossRef Shih T-H, Fan X (2009) Comparing response rates in e-mail and paper surveys: a meta-analysis. Educ Res Rev 4:26–40CrossRef
19.
go back to reference Seeram E (2009) Computed tomography: Physical principles, clinical applications and quality control, 3rd edn. Sanders, St Louis Seeram E (2009) Computed tomography: Physical principles, clinical applications and quality control, 3rd edn. Sanders, St Louis
20.
go back to reference Hsieh J (2009) Computed tomography. Principles, design, artifacts and recent advances, 2nd edn. SPIE & Wiley, Bellingham Hsieh J (2009) Computed tomography. Principles, design, artifacts and recent advances, 2nd edn. SPIE & Wiley, Bellingham
21.
go back to reference ACR (2011) ACR practice guidelines for performing and interpreting diagnostic computed tomography. American College of Radiology, Reston ACR (2011) ACR practice guidelines for performing and interpreting diagnostic computed tomography. American College of Radiology, Reston
22.
go back to reference Kalra MK et al (2005) Detection of urinary tract stones at low-radiation-dose CT with z-axis automatic tube current modulation: phantom and clinical studies. Radiology 235:523–529PubMedCrossRef Kalra MK et al (2005) Detection of urinary tract stones at low-radiation-dose CT with z-axis automatic tube current modulation: phantom and clinical studies. Radiology 235:523–529PubMedCrossRef
23.
go back to reference Kluner C et al (2006) Does ultra-low-dose CT with a radiation dose equivalent to that of KUB suffice to detect renal and ureteral calculi? J Comput Assist Tomogr 30:44–50PubMedCrossRef Kluner C et al (2006) Does ultra-low-dose CT with a radiation dose equivalent to that of KUB suffice to detect renal and ureteral calculi? J Comput Assist Tomogr 30:44–50PubMedCrossRef
24.
go back to reference Christe A et al (2011) CT screening and follow-up of lung nodules: Effects of tube current-time setting and nodule size and density on detectability and of tube current-time setting on apparent size. AJR Am J Roentgenol 197:623–630PubMedCrossRef Christe A et al (2011) CT screening and follow-up of lung nodules: Effects of tube current-time setting and nodule size and density on detectability and of tube current-time setting on apparent size. AJR Am J Roentgenol 197:623–630PubMedCrossRef
25.
go back to reference Tack D et al (2003) Comparison between low-dose and standard-dose multidetector CT in patients with suspected chronic sinusitis. AJR Am J Roentgenol 181:939–944PubMedCrossRef Tack D et al (2003) Comparison between low-dose and standard-dose multidetector CT in patients with suspected chronic sinusitis. AJR Am J Roentgenol 181:939–944PubMedCrossRef
26.
go back to reference Soderberg M, Gunnarsson M (2010) Automatic exposure control in computed tomography—an evaluation of systems from different manufacturers. Acta Radiol 51:625–634PubMedCrossRef Soderberg M, Gunnarsson M (2010) Automatic exposure control in computed tomography—an evaluation of systems from different manufacturers. Acta Radiol 51:625–634PubMedCrossRef
27.
go back to reference Guite KM et al (2011) Ionizing radiation in abdominal CT: Unindicated multiphase scans are an important source of medically unnecessary exposure. J Am Coll Radiol 8:756–761PubMedPubMedCentralCrossRef Guite KM et al (2011) Ionizing radiation in abdominal CT: Unindicated multiphase scans are an important source of medically unnecessary exposure. J Am Coll Radiol 8:756–761PubMedPubMedCentralCrossRef
28.
go back to reference McNitt-Gray M (2011) Tube current modulation approaches: overview, practical issues and potential pitfalls. AAPM 2011 Summit on CT Dose, Denver McNitt-Gray M (2011) Tube current modulation approaches: overview, practical issues and potential pitfalls. AAPM 2011 Summit on CT Dose, Denver
29.
go back to reference Haramati N et al (1994) CT scans through metal scanning technique versus hardware composition. Comput Med Imaging and Graph 18:429–434CrossRef Haramati N et al (1994) CT scans through metal scanning technique versus hardware composition. Comput Med Imaging and Graph 18:429–434CrossRef
30.
go back to reference Rizzo SM et al (2005) Do metallic endoprostheses increase radiation dose associated with automatic tube-current modulation in abdominal-pelvic MDCT? A phantom and patient study. AJR Am J Roentgenol 184:491–496PubMedCrossRef Rizzo SM et al (2005) Do metallic endoprostheses increase radiation dose associated with automatic tube-current modulation in abdominal-pelvic MDCT? A phantom and patient study. AJR Am J Roentgenol 184:491–496PubMedCrossRef
31.
go back to reference Dalal T et al (2005) Metallic prosthesis: technique to avoid increase in CT radiation dose with automatic tube current modulation in a phantom and patients. Radiology 236:671–675PubMedCrossRef Dalal T et al (2005) Metallic prosthesis: technique to avoid increase in CT radiation dose with automatic tube current modulation in a phantom and patients. Radiology 236:671–675PubMedCrossRef
32.
go back to reference Winklehner A et al (2011) Automated attenuation-based tube potential selection for thoracoabdominal computed tomography angiography: improved dose effectiveness. Investig Radiol 46:767–773CrossRef Winklehner A et al (2011) Automated attenuation-based tube potential selection for thoracoabdominal computed tomography angiography: improved dose effectiveness. Investig Radiol 46:767–773CrossRef
33.
go back to reference Sigal-Cinqualbre AB et al (2004) Low-kilovoltage multi-detector row chest CT in adults: feasibility and effect on image quality and iodine dose. Radiology 231:169–174PubMedCrossRef Sigal-Cinqualbre AB et al (2004) Low-kilovoltage multi-detector row chest CT in adults: feasibility and effect on image quality and iodine dose. Radiology 231:169–174PubMedCrossRef
34.
go back to reference Leschka S et al (2008) Low kilovoltage cardiac dual-source CT: attenuation, noise, and radiation dose. Eur Radiol 18:1809–1817PubMedCrossRef Leschka S et al (2008) Low kilovoltage cardiac dual-source CT: attenuation, noise, and radiation dose. Eur Radiol 18:1809–1817PubMedCrossRef
35.
go back to reference Kim MJ et al (2009) Multidetector computed tomography chest examinations with low-kilovoltage protocols in adults: effect on image quality and radiation dose. J Comput Assist Tomogr 33:416–421PubMedCrossRef Kim MJ et al (2009) Multidetector computed tomography chest examinations with low-kilovoltage protocols in adults: effect on image quality and radiation dose. J Comput Assist Tomogr 33:416–421PubMedCrossRef
36.
go back to reference Bogot NR et al (2011) Image quality of low-energy pulmonary CT angiography: comparison with standard CT. AJR Am J Roentgenol 197:W273–W278PubMedCrossRef Bogot NR et al (2011) Image quality of low-energy pulmonary CT angiography: comparison with standard CT. AJR Am J Roentgenol 197:W273–W278PubMedCrossRef
37.
go back to reference Keat N (2005) CT scanner automatic exposure control systems. Report 05016. ImPACT, London Keat N (2005) CT scanner automatic exposure control systems. Report 05016. ImPACT, London
38.
go back to reference Nakayama Y et al (2005) Abdominal CT with low tube voltage: preliminary observations about radiation dose, contrast enhancement, image quality, and noise. Radiology 237:945–951PubMedCrossRef Nakayama Y et al (2005) Abdominal CT with low tube voltage: preliminary observations about radiation dose, contrast enhancement, image quality, and noise. Radiology 237:945–951PubMedCrossRef
39.
go back to reference Primak AN et al (2006) Relationship between noise, dose, and pitch in cardiac multidetector row CT. Radiographics 26:1785–1794PubMedCrossRef Primak AN et al (2006) Relationship between noise, dose, and pitch in cardiac multidetector row CT. Radiographics 26:1785–1794PubMedCrossRef
40.
go back to reference Goldman LW (2007) Principles of CT: radiation dose and image quality. J Nucl Med Technol 35:213–225PubMedCrossRef Goldman LW (2007) Principles of CT: radiation dose and image quality. J Nucl Med Technol 35:213–225PubMedCrossRef
41.
go back to reference Husband J, Padhani A (2006) Recommendations for cross-sectional imaging in cancer management. Royal College of Radiologists, London Husband J, Padhani A (2006) Recommendations for cross-sectional imaging in cancer management. Royal College of Radiologists, London
42.
go back to reference Kumar R (2011) Research methodology. A step by step guide for beginners. SAGE Publications, London Kumar R (2011) Research methodology. A step by step guide for beginners. SAGE Publications, London
Metadata
Title
A questionnaire survey reviewing radiologists’ and clinical specialist radiographers’ knowledge of CT exposure parameters
Authors
S. J. Foley
M. G. Evanoff
L. A. Rainford
Publication date
01-10-2013
Publisher
Springer Berlin Heidelberg
Published in
Insights into Imaging / Issue 5/2013
Electronic ISSN: 1869-4101
DOI
https://doi.org/10.1007/s13244-013-0282-4

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