title: Radiation Dose Survey for Common Computed Tomography Exams: 2013 British Columbia Results.
abstract: In 2013 Health Canada conducted a national survey of computed tomography (CT) radiation usage. We analysed contributions from all 7 public health authorities in the province of British Columbia, which covered scanner age, number of slices, and common adult protocols (≥ 19 years: 70 ± 20 kg, head, chest, abdomen/pelvis, and trunk). Patient doses were recorded for common protocols. Diagnostic reference levels (DRLs) was calculated using scanner data with >10 patient doses recorded for each protocol. Data was analysed based on image reconstruction (filtered backprojection vs iterative reconstruction [IR] vs IR available but not in use). Provincial response was 92%, with 59 of 64 CT data used for analysis. The average scanner age was 5.5 years old, with 39% of scanners installed between 2008-2013; 78.5% of scanners were multislice (>64 slices), and 44% of scanners had IR available. Overall British Columbia DRLs were: head = 1305, chest = 529, abdomen/pelvis = 819, and trunk = 1225. DRLs were consistent with Health Canada recommendations and other Canadian published values, but above international standards. For sites with IR available, less than 50% used this technology routinely for head, chest and trunk exams. Overall, use of IR reduced radiation usage between 11%-32% compared to filtered backprojection, while sites using IR vs IR available used 30%/43% less radiation for head/chest exams (P < .05). No significant difference was observed for abdomen/pelvis exams (P = .385). With the fast pace of CT technical advancement, DRLs should reflect the technology used, instead of just globally applied to anatomical regions. Federal guidelines should be updated at a higher frequency to reflect new technology. In addition, new technologies must be utilised to optimize image quality vs radiation usage.
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada; Vancouver Coastal Health Authority, Vancouver, British Columbia, Canada. Electronic address: yogesh.thakur@vch.ca.
authors.forename: Yogesh
authors.initials: Y
authors.lastname: Thakur
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada; Diagnostic Imaging Services, Interior Health, Kelowna, British Columbia, Canada; Mathematics, Statistics, Physics & Computer Science, University of British Columbia Okanagan, Kelowna, British Columbia, Canada.
authors.forename: Thorarin A
authors.initials: TA
authors.lastname: Bjarnason
authors.affiliation: Vancouver Island Health Authority, Victoria, British Columbia, Canada.
authors.forename: Patricia
authors.initials: P
authors.lastname: Baxter
authors.affiliation: Northern Health Authority, Prince George, British Columbia, Canada.
authors.forename: Mitch
authors.initials: M
authors.lastname: Griffith
authors.affiliation: The Ministry of Health, The Province of British Columbia, Victoria, British Columbia, Canada.
authors.forename: Kirk
authors.initials: K
authors.lastname: Eaton
mesh_terms: D000328:Adult; D001955:British Columbia; D006801:Humans; D011829:Radiation Dosage; D011795:Surveys and Questionnaires; D014057:Tomography, X-Ray Computed / Q000295:instrumentation
keywords: Computed tomography; Computed tomography dose; Diagnostic reference levels; Medical imaging; Radiation