Browse by author
Lookup NU author(s): Professor Mark Pearce,
Dr Jane Salotti,
Dr Richard Harbron
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Objective: Although CT scans provide great medical benefits, concerns have been raised about the magnitude of possible associated cancer risk, particularly in children who are more sensitive to radiation than adults. Unnecessary high doses during CT examinations can also be delivered to children, if the scan parameters are not adjusted for patient age and size. We conducted the first survey to directly assess the trends in CT scan parameters and doses for paediatric CT scans performed in Great Britain between 1978 and 2008.Methods: We retrieved 1073 CT film sets from 36 hospitals. The patients were 0-19 years old, and CT scans were conducted between 1978 and 2008. We extracted scan parameters from each film including tube current-time product [milliampere seconds (mAs)], tube potential [peak kilovoltage (kVp)] and manufacturer and model of the CT scanner. We estimated the mean mAs for head and trunk (chest and abdomen/pelvis) scans, according to patient age (0-4, 5-9, 10-14 and 15-19 years) and scan year (<1990, 1990-1994, 1995-1999 and >= 2000), and then derived the volumetric CT dose index and estimated organ doses.Results: For head CT scans, mean mAs decreased by about 47% on average from before 1990 to after 2000, with the decrease starting around 1990. The mean mAs for head CTs did not vary with age before 1990, whereas slightly lower mAs values were used for younger patients after 1990. Similar declines in mAs were observed for trunk CTs: a 46% decline on an average from before 1990 to after 2000. Although mean mAs for trunk CTs did not vary with age before 1990, the value varied markedly by age, from 63mAs for age 0-4 years compared with 315mAs for those aged >15 years after 2000. No material changes in kVp were found. Estimated brain-absorbed dose from head CT scans decreased from 62mGy before 1990 to approximately 30mGy after 2000. For chest CT scans, the lung dose to children aged 0-4 years decreased from 28mGy before 1990 to 4mGy after 2000.Conclusion: We found that mAs for head and trunk CTs was approximately halved starting around 1990, and age-specific mAs was generally used for paediatric scans after this date. These changes will have substantially reduced the radiation exposure to children from CT scans in Great Britain.Advances in knowledge: The study shows that mAs and major organ doses for paediatric CT scans in Great Britain began to decrease around 1990.
Author(s): Lee C, Pearce MS, Salotti JA, Harbron RW, Little MP, Mchugh K, Chapple CL, De Gonzalez AB
Publication type: Article
Publication status: Published
Journal: British Journal of Radiology
Online publication date: 04/03/2016
Acceptance date: 09/02/2016
ISSN (print): 0007-1285
ISSN (electronic): 1748-880X
Publisher: British Institute of Radiology
Altmetrics provided by Altmetric