Ekpo Ernest U, Adejoh Thomas, Akwo Judith D, Emeka Owujekwe C, Modu Ali A, Abba Mohammed, Adesina Kudirat A, Omiyi David O, Chiegwu Uche H
Faculty of Health Sciences, The University of Sydney, Discipline of Medical Radiation Sciences, Cumberland Campus, 75 East Street, Lidcombe, NSW 2141, Australia.
J Radiol Prot. 2018 Jun;38(2):525-535. doi: 10.1088/1361-6498/aaaaf8. Epub 2018 Jan 29.
To explore doses from common adult computed tomography (CT) examinations and propose national diagnostic reference levels (nDRLs) for Nigeria.
This retrospective study was approved by the Nnamdi Azikiwe University and University Teaching Hospital Institutional Review Boards (IRB: NAUTH/CS/66/Vol8/84) and involved dose surveys of adult CT examinations across the six geographical regions of Nigeria and Abuja from January 2016 to August 2017. Dose data of adult head, chest and abdomen/pelvis CT examinations were extracted from patient folders. The median, 75th and 25th percentile CT dose index volume (CTDI) and dose-length-product (DLP) were computed for each of these procedures. Effective doses (E) for these examinations were estimated using the k conversion factor as described in the ICRP publication 103 (E = ).
The proposed 75th percentile CTDI for head, chest, and abdomen/pelvis are 61 mGy, 17 mGy, and 20 mGy, respectively. The corresponding DLPs are 1310 mGy.cm, 735 mGy.cm, and 1486 mGy.cm respectively. The effective doses were 2.75 mSv (head), 10.29 mSv (chest), and 22.29 mSv (abdomen/pelvis).
Findings demonstrate wide dose variations within and across centres in Nigeria. The results also show CTDI comparable to international standards, but considerably higher DLP and effective doses.
探讨成人常见计算机断层扫描（CT）检查的剂量，并为尼日利亚提出国家诊断参考水平（nDRLs）。
这项回顾性研究经纳姆迪·阿齐克韦大学和大学教学医院机构审查委员会批准（IRB：NAUTH/CS/66/Vol8/84），涉及2016年1月至2017年8月尼日利亚六个地理区域和阿布贾的成人CT检查剂量调查。从患者文件夹中提取成人头部、胸部和腹部/骨盆CT检查的剂量数据。计算这些检查中每项检查的中位、第75和第25百分位数CT剂量指数体积（CTDI）和剂量长度乘积（DLP）。使用国际辐射防护委员会出版物103中所述的k转换因子估算这些检查的有效剂量（E）（E = ）。
提议的头部、胸部和腹部/骨盆第75百分位数CTDI分别为61 mGy、17 mGy和20 mGy。相应的DLP分别为1310 mGy.cm、735 mGy.cm和1486 mGy.cm。有效剂量分别为2.75 mSv（头部）、10.29 mSv（胸部）和22.29 mSv（腹部/骨盆）。
研究结果表明尼日利亚各中心内部和之间的剂量存在很大差异。结果还显示CTDI与国际标准相当，但DLP和有效剂量明显更高。
