Updated Australian diagnostic reference levels for adult CT

Abstract

Introduction In 2018, ARPANSA published updated national DRLs for adult CT, which were first published in 2012, and augmented the national DRL categories. This paper presents the updated national DRLs and describes the process by which they were produced. Methods Examine patient survey data submitted to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) National Diagnostic Reference Level Service (NDRLS). Determine the quartiles of the distributions of median survey dose metrics with categorisation by procedure type. Engage a liaison panel representing the radiology professions to review procedure categories and recommend revised national DRLs. The revised NDRL procedure categories are: head (non‐contrast brain (trauma/headache)), cervical spine (Non‐contrast (trauma)), soft‐tissue neck (post‐contrast (oncology)), chest (post‐contrast (oncology)), abdomen–pelvis (post‐contrast (oncology)), kidney–ureter–bladder (non‐contrast (suspected renal colic)), chest–abdomen–pelvis (post‐contrast (oncology)) and lumbar spine (non‐contrast (degenerative pain)). Results The existing six procedure categories were revised and refined. Updated Australian national diagnostic reference levels for adult CT were recommended and endorsed for eight procedure categories: head (52 mGy/880 mGycm), cervical spine (23 mGy/470 mGycm),soft‐tissue neck (17 mGy/450 mGycm), chest (10 mGy/390 mGycm), abdomen–pelvis (13 mGy/600 mGycm), kidney–ureter–bladder (13 mGy/600 mGycm), chest–abdomen–pelvis (11 mGy/940 mGycm) and lumbar spine (26 mGy/670 mGycm). The updated national DRLs are between 12 and 26% lower than the previous DRLs for dose‐length product and between 13 and 63% lower for volume computed tomography dose index. Conclusions Australian national DRLs for adult CT have been reviewed and revised. The revised national DRLs are lower, better reflecting current practice among imaging facilities in Australia. The revised Australian national DRLs are similar to those in other developed countries.

National diagnostic reference levels: What they are, why we need them and what’s next

“…In early 2018 the data collected by the NDRLS were reviewed by a liaison panel comprising representatives from the Commonwealth Department of Health (DoH), RANZCR, the Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM), the Australian Diagnostic Imaging Association (ADIA) and the Australian Society for Medical Imaging and Radiation Therapy (ASMIRT). Revised DRLs for CT procedures on adult patients were established using the data submitted to the NDRLS during the 2017 calendar year and published on the ARPANSA website in June 2018 16 …”

“…Revised DRLs for CT procedures on adult patients were established using the data submitted to the NDRLS during the 2017 calendar year and published on the ARPANSA website in June 2018. 16 The 2018 review saw the addition of kidney-ureterbladder scans to the list of scan types and also the separation of the original neck category into cervical spine and soft-tissue neck categories. After reviewing data collected in the 2019 calendar year, updated DRLs were endorsed for these three scan types and published on the ARPANSA website in March 2021.…”

The status of radiation protection in medicine in the Asia‐Pacific region

“…It is not specific to an individual patient, but derived from data collated locally, regionally or nationally. 16 Several Asia-Pacific countries such as Australia, Malaysia and Thailand have developed national DRLs [17][18][19] and published widely on this.…”

Iterative Model Reconstruction in Lumbar Spine Image Retrieval from Computed Tomography of the Abdomen and Pelvis

“…6 Data from the Australian Radiation Protection and Nuclear Safety Agency have documented higher dose levels for CT lumbar spine (26 mGy) compared with CTAP (13 mGy). 7 The rise of iterative reconstruction (IR) algorithms for CT in recent years has decreased the need for radiation dose increases in order to improve image quality. 8,9 Filtered back projection was previously the most commonly used reconstruction algorithm for conventional CT imaging.…”