Establishment of faculty reference level in computed tomography in selective examinations in a single institution in South Australia

Introduction: There have been several national and international publications relating to patient dose management, predominantly in the United States and European countries.1,2 In South Australia, no recent study has been published surveying common adult CT examinations. This study aims to establish a faculty reference level (FRL) for one scanner in our institution.

Methods: Data was retrospectively collected from our Toshiba Aquilion One Vision 320-slice from 26 December 2016 to 26 June 2017. Examinations were separated as contrast or non-contrast studies, and single phase or multi-phases. Common CT examinations, including chest, chest/abdomen/pelvis, and abdomen/pelvis were reported. The median, mean (50th percentile) and 75th percentile for the dose spread were calculated according to the examination.

Results: There was a total of 1571 CT examinations performed between 26 December 2016 and 26 June 2017 using the Toshiba scanner in our institution; 262 of these examinations met the inclusion and exclusion criteria. The examinations for our Toshiba scanner (established as median value of CTDIvol and DLP) were distributed as CT chest contrast (n = 67, 25.6%, 6 mGy, 219.1 mGy.cm), CT chest non-contrast (n = 41, 15.6%, 5.7 mGy, 190.6 mGy), CT abdomen/pelvis contrast (single phase) (n = 49, 18.7%, 6.5 mGy, 330.5 mGy.cm), CT abdomen/pelvis contrast (multi-phase) (n = 33, 12.6%, 8.93 mGy, 1037.5 mGy.cm), CT abdomen/pelvis non-contrast (n = 12, 4.6%, 10.1 mGy, 289.9 mGy.cm) and CT chest/abdomen/pelvis (n = 60, 22.9%, 7.15 mGy, 619.4 mGy.cm).

Conclusion: This data provided information that our own institution and others can use for quality improvement activities. Future research is required to allow for analysis to include more CT examinations in various scanners.