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Purpose: Follow-up study to observe if provincial mean effective radiation dose for head, chest, and abdomen-pelvis (AP) computed tomographies (CTs) remained stable or changed since the initial 2006 survey., Methods: Data were collected in July 2008 from Saskatchewan's 13 diagnostic CT scanners of 3358 CT examinations. These data included the number of scan phases and projected dose length product (DLP). Technologists compared projected DLP with 2006 reference data before scanning. Projected DLP was converted to effective dose (ED) for each head, chest, and AP CT. The total dose that the patients received with scans of multiple body parts at the same visit also was determined., Results: The mean (± SD) provincial ED was 3.4 ± 1.6 mSv for 1023 head scans (2.7 ± 1.6 mSv in 2006), 9.6 ± 4.8 mSv for 588 chest scans (11.3 ± 8.9 mSv in 2006), and 16.1 ± 9.9 mSv for 983 AP scans (15.5 ± 10.0 mSv in 2006). Single-phase multidetector row CT ED decreased by 31% for chest scans (9.5 ± 3.9 mSv vs 13.7 ± 9.7 mSv in 2006) and 17% for AP scans (13.9 ± 6.0 mSv vs 16.8 ± 10.6 mSv in 2006) and increased by 19% for head scans (3.2 ± 1.2 mSv vs 2.7 ± 1.5 mSv in 2006). The total patient dose was highest (33.8 ± 10.1 mSv) for the 20 patients who received head, neck, chest, and AP scans during a single visit. Because of increased utilisation and the increased CT head dose, Saskatchewan per capital radiation dose from CT increased by 21% between 2006 and 2008 (1.14 vs 1.38 mSv/person per year)., Conclusion: Significant dose and variation reduction was seen for single-phase CT chest and AP examinations between 2006 and 2008, whereas CT head dose increased over the same interval. These changes, combined with increased utilisation, resulted in per capita increase in radiation dose from CT between the 2 studies., (Copyright © 2012 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.)

Objective: To calculate the effective dose from diagnostic computed tomography (CT) scans in Saskatchewan, Canada, and compare with other reported dose levels., Methods: Data from CT scans were collected from 12 scanners in 7 cities across Saskatchewan. The patient age, scan type, and selected technique parameters including the dose length product and the volume computed tomography dose index were collected for a 2-week period. This information then was used to calculate effective doses patients are exposed to during CT examinations. Data from 2,061 clinically indicated CT examinations were collected, and of them 1,690 were eligible for analysis. Every examination during a 2-week period was recorded without selection., Results: The average provincial estimated patient dose was as follows: head, 2.7 mSv (638 scans; standard deviation [SD], +/-1.6); chest, 11.3 mSv (376 scans; SD, +/-8.9); abdomen-pelvis, 15.5 mSv (578 scans; SD, +/-10.0); abdomen, 11.7 mSv (80 scans; SD, +/-11.48), and pelvis, 8.6 mSv (18 scans; SD, +/-6.04). Significant variation in dose between the CT scanners was observed (P = .049 for head, P = .001 for chest, and P = .034 for abdomen-pelvis)., Conclusions: Overall, the estimated dose from diagnostic CT examinations was similar to other previously published Canadian data from British Columbia. This dose varied slightly from some other published standards, including being higher than those found in a review conducted in the United Kingdom in 2003.