van der Merwe Cornelis M, Mahomed Nasreen
Department of Radiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
SA J Radiol. 2020 Oct 16;24(1):1823. doi: 10.4102/sajr.v24i1.1823. eCollection 2020.
Diagnostic reference levels (DRLs) are a crucial element of auditing radiation doses in paediatric computed tomography (CT). Currently, there are no national paediatric CT DRLs in South Africa.
The aim of this article was to establish local paediatric DRLs for CT examinations at two academic hospitals and to compare paediatric CT radiation output levels with established DRLs in the developed and developing world.
Computed Tomography Dose Index (CTDI) and dose length product (DLP) values were collected from CT examinations performed at two university hospitals for patients aged 0-15 years, during 01 November 2016-30 April 2017. The 75th percentile of the data distribution was calculated for each CT examination type and age group, further categorised into routine working hours and after-hours for both hospitals and statistically compared.
Of the 1031 CT examinations performed, CT brain examination was the most common (755/1031; 72.23%). DLP values were increased in the after-hours categories compared to regular working hours at both hospitals. The largest increase was in the 0-1 year age group (150.56%). With the exception of CT Chest and CT abdomen in the 0-1 year age group, the CTDI and DLP values compared favourably to international standards.
Most of the calculated DRLs are acceptable and internationally comparable. This likely indicates effective reduction techniques and protocols. Computed tomography body examination protocols for 0-1 year patients should be reviewed. Strategies should be implemented to limit higher doses in after-hours examinations.
诊断参考水平(DRLs)是儿科计算机断层扫描(CT)辐射剂量审核的关键要素。目前,南非尚无全国性的儿科CT诊断参考水平。
本文旨在确定两家学术医院儿科CT检查的本地诊断参考水平,并将儿科CT辐射输出水平与发达国家和发展中国家已确立的诊断参考水平进行比较。
收集2016年11月1日至2017年4月30日期间在两家大学医院为0至15岁患者进行的CT检查的计算机断层扫描剂量指数(CTDI)和剂量长度乘积(DLP)值。计算每种CT检查类型和年龄组数据分布的第75百分位数,进一步按两家医院的常规工作时间和非工作时间进行分类,并进行统计学比较。
在进行的1031例CT检查中,CT脑部检查最为常见(755/1031;72.23%)。两家医院非工作时间类别的DLP值均高于正常工作时间。0至1岁年龄组的增幅最大(150.56%)。除0至1岁年龄组的CT胸部和CT腹部外,CTDI和DLP值与国际标准相比情况良好。
大多数计算得出的诊断参考水平是可接受的且具有国际可比性。这可能表明有效的剂量降低技术和方案。应对0至1岁患者的计算机断层扫描身体检查方案进行审查。应实施策略以限制非工作时间检查中的较高剂量。