The implementation of diagnostic reference levels to Australian radiology practice

At the present time, there is no national surveillance of the increasing ionising radiation dose to the population from diagnostic imaging procedures. As the number of procedures undertaken is increasing, it is expected that the population dose will also increase. A substantial component of that contribution is from multi-detector computed tomography (MDCT) systems. The Australian Radiation Protection & Nuclear Safety Agency (ARPANSA) estimates that the growth in MDCT scans, based on Medicare Benefits Schedule data, is increasing at approximately 9% per annum, with over 2 million MDCT scans being performed in 2009. The caput effective dose (mSv) from this modality is expected to be approaching 1.2 mSv per annum. If current dose-detriment models are accurate, the risk of induction of carcinogenic detriment from current MDCT scanning patterns is a significant public health issue that requires a concerted and ongoing response. For the application of ionising radiation in medicine, the International Commission on Radiological Protection recommends the conservative philosophy of Justification and Optimisation via the measurement of 'Diagnostic Reference Levels' to limit the potential overexposure of patients and decrease the overall population burden. The Australian government has commissioned ARPANSA to survey, calculate and construct representative national diagnostic reference levels for diagnostic imaging modalities that use ionising radiation. This will be achieved in close consultation with the professional organisations who represent the professionals responsible for the use of ionising radiation in diagnostic imaging.