Masoomi Michael, Al-Kandari Latifah, Al-Shammeri Iman, Elrahman Hany, Al-Shammeri Jehan
Department of Nuclear Medicine and Molecular Imaging, Adan Hospital, MOH, Hadiya, 46020, Kuwait.
Research and Innovation Department, Portsmouth University Hospital, Portsmouth, United Kingdom.
BJR Open. 2024 Oct 4;6(1):tzae032. doi: 10.1093/bjro/tzae032. eCollection 2024 Jan.
Diagnostic reference levels (DRLs) for CT in PET-CT are limited, and published DRLs from other countries may not be directly applicable to the State of Kuwait (KW). The authors aimed to carry out the final phase of a 3-year study on DRLs in KW, supporting optimization and dose reduction as imaging technology advances.
In this cohort study, 400 adult oncology patients from 8 PET-CT centres were included, following the same procedures as in the first (2018) and second (2020) years, in accordance with the MOH-KW Ethical Committee's recommendations. The CT dose index (CTDIvol), dose-length product (DLP), and scan length were recorded, and the median, mean, standard deviation, as well as the 75th and 25th percentiles, along with the whole-body (WB) effective dose (ED), were calculated. Comparative studies were conducted to track implementation and identify any shortfalls.
In this study, half-body (HB) and WB scans accounted for 66% and 34% of the total 400 cases, respectively. The proposed local DRL practice among the 8 centres in the 2022 study exhibited a maximum variation of 25%, showing a 30% improvement over 2020. The achievable local DRL remained consistent with 2020 levels. Comparative results of the third quartile DLP (476 mGy cm) and CTDIvol (4 mGy) values for 2022 indicated lower values for the third phase (400 entries) compared to 2020, with a 1.5-fold variation in DLP. The calculated ED for WB scans ranged from 2.6 to 7.1 mSv, with mean values of 4.7 ± 1.25 mSv, using a conversion factor ( = 0.0093 mSv/mGy/cm). The 2022 proposed national diagnostic reference levels (NDRLs) for HB (469 mGy cm, 4.0 mGy) were lower than the Swiss National Data (620 mGy cm, 6.0 mGy) and France (628 mGy cm, 6.6 mGy), but slightly higher than those of the United Kingdom (400 mGy cm, 4.3 mGy), despite the Swiss having about 5000 entries, France 1000 entries, and the United Kingdom 370 HB entries.
There was a 11.1% continuous improvement in NDRL for 2022 compared to 9.1% in 2020 and 13% in 2018, demonstrating a trend of enhanced optimization.
The data established a trend of NDRL for WBCT (PET-CT) that can serve as a national databank for ongoing optimization. This promotes improvements in patient protection and quality care within the clinical environment of the State of Kuwait, aligning with the strategic goals of Kuwait Vision-2035.
正电子发射断层显像-计算机断层扫描（PET-CT）中CT的诊断参考水平（DRLs）有限，其他国家公布的DRLs可能不适用于科威特国（KW）。作者旨在开展一项为期3年的科威特DRLs研究的最后阶段，随着成像技术的进步，支持优化和降低剂量。
在这项队列研究中，按照科威特卫生部伦理委员会的建议，纳入了来自8个PET-CT中心的400名成年肿瘤患者，采用与第一年（2018年）和第二年（2020年）相同的程序。记录CT剂量指数（CTDIvol）、剂量长度乘积（DLP）和扫描长度，并计算中位数、均值、标准差以及第75和第25百分位数，以及全身（WB）有效剂量（ED）。进行比较研究以跟踪实施情况并发现任何不足之处。
在本研究中，半身（HB）和WB扫描分别占400例总数的66%和34%。2022年研究中8个中心提出的当地DRL实践显示最大差异为25%，比2020年提高了30%。可实现的当地DRL与2020年水平保持一致。2022年第三四分位数DLP（476 mGy cm）和CTDIvol（4 mGy）值的比较结果表明，与2020年相比，第三阶段（400份记录）的值更低，DLP有1.5倍的差异。使用转换因子（=0.0093 mSv/mGy/cm）计算的WB扫描ED范围为2.6至7.1 mSv，平均值为4.7±1.25 mSv。2022年提出的科威特国HB的国家诊断参考水平（NDRLs）（469 mGy cm, 4.0 mGy）低于瑞士国家数据（620 mGy cm, 6.0 mGy）和法国（628 mGy cm, 6.6 mGy），但略高于英国（4
