The British Journal of Radiology, Vol 73, Issue 865 43-50, Copyright © 2000 by British Institute of Radiology

ARTICLES

Application of draft European Commission reference levels to a regional CT dose survey

J Clarke, K Cranley, J Robinson, PH Smith and A Workman
Department of Radiology, Antrim Area Hospital, Northern Ireland.

A survey of CT doses in Northern Ireland in the period between October 1995 and March 1997 was carried out. The survey included all but one of the 10 scanners in use at the time, and, additionally, two others that were replacement machines. The method used was to study standard protocols and calculate doses to the NRPB mathematical phantom, so that a direct comparison could be made with other surveys carried out in a similar fashion elsewhere. The survey addressed the patient radiation dose but not image quality or clinical outcomes. It is estimated that in Northern Ireland the contribution to collective dose to the population from CT is about 40% of that from all medical X-rays. The proposed European Commission reference quantities, weighted CT dose index and dose-length product were computed and their potential use evaluated. A full study of mean values of effective dose per examination revealed the average dose per examination was not significantly different from that found in the 1989 UK survey, although several procedures gave rise to doses that were high enough to be investigated with a view to justification or reduction. One of the scanners was found to give consistently high doses. It is likely that a revision of the mAs values used on this scanner will produce a significant reduction in patient doses without compromising image quality. When compared with the draft EC reference levels, fewer procedures were found to have excessively high dose values. The proposed EC reference levels would therefore be useful for continual monitoring of CT dose status, but do not appear to provide as comprehensive an assessment of patient exposure as that given by consideration of effective doses.

This article has been cited by other articles:

				A J Van Der Molen, W J H Veldkamp, and J Geleijns 16-slice CT: achievable effective doses of common protocols in comparison with recent CT dose surveys Br. J. Radiol., April 1, 2007; 80(952): 248 - 255. [Abstract] [Full Text] [PDF]

				V. Tsapaki, J. E. Aldrich, R. Sharma, M. A. Staniszewska, A. Krisanachinda, M. Rehani, A. Hufton, C. Triantopoulou, P. N. Maniatis, J. Papailiou, et al. Dose Reduction in CT while Maintaining Diagnostic Confidence: Diagnostic Reference Levels at Routine Head, Chest, and Abdominal CT--IAEA-coordinated Research Project Radiology, September 1, 2006; 240(3): 828 - 834. [Abstract] [Full Text] [PDF]

				J.D. Newell Jr, J.C. Hogg, and G.L. Snider Report of a workshop: quantitative computed tomography scanning in longitudinal studies of emphysema Eur. Respir. J., May 1, 2004; 23(5): 769 - 775. [Abstract] [Full Text] [PDF]

				C J Koller, J P Eatough, and A Bettridge Variations in radiation dose between the same model of multislice CT scanner at different hospitals Br. J. Radiol., November 1, 2003; 76(911): 798 - 802. [Abstract] [Full Text] [PDF]

				M. Mahesh, J. C. Scatarige, J. Cooper, and E. K. Fishman Dose and Pitch Relationship for a Particular Multislice CT Scanner Am. J. Roentgenol., December 1, 2001; 177(6): 1273 - 1275. [Abstract] [Full Text] [PDF]

				J C Clarke, K Cranley, B E Kelly, K Bell, and P H S Smith Provision of MRI can significantly reduce CT collective dose Br. J. Radiol., October 1, 2001; 74(886): 926 - 931. [Abstract] [Full Text] [PDF]

				V Tsapaki, S Kottou, and D Papadimitriou Application of European Commission reference dose levels in CT examinations in Crete, Greece Br. J. Radiol., September 1, 2001; 74(885): 836 - 840. [Abstract] [Full Text] [PDF]

				M T Crawley, A Booth, and A Wainwright A practical approach to the first iteration in the optimization of radiation dose and image quality in CT: estimates of the collective dose savings achieved Br. J. Radiol., July 1, 2001; 74(883): 607 - 614. [Abstract] [Full Text] [PDF]