Tao Shu Min, Zhou Fan, Schoepf U Joseph, Johnson Addison A, Lin Zhu Xiao, Zhou Chang Sheng, Lu Guang Ming, Zhang Long Jiang
1 Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, PR China.
2 Medical Imaging Center, Affiliated Hospital of Nantong University, Nantong, PR China.
Acta Radiol. 2019 Jun;60(6):687-693. doi: 10.1177/0284185118799513. Epub 2018 Sep 10.
As abdominal computed tomography (CT) radiation dose can be higher compared with other organ systems, monitoring the radiation exposure from this exam type is especially important.
To evaluate the effect of abdominal contrast-enhanced CT (CE-CT) on levels of DNA double-strand breaks (DSBs) in peripheral blood lymphocytes.
This study was performed in two parts: (i) an in vitro study: venous blood samples from 12 volunteers were divided into four groups. Samples in group A did not undergo radiation exposure, while groups B, C, and D received one CT scan with 1-3 times the radiation dose equivalent to abdominal CE-CT scan, respectively; and (ii) an in vivo study: blood was taken before CT and 5 min after CT in 30 patients. Lymphocytes were isolated and stained by immunofluorescence of γ-H2AX protein. DSB levels were compared by variance analysis or paired t-test. The relationship between radiation dose and γ-H2AX focus increase was analyzed using Pearson correlation analysis.
In the in vitro study, DSBs levels in groups B, C, and D were 49.4%, 96.6%, and 149.4% higher than those in Group A, respectively (all P < 0.001). Radiation dose in the four subgroups had a linear correlation to DSB levels ( P < 0.001). In the in vivo study, the DSB level was 43.5% higher after CT ( P < 0.001).
Abdominal CE-CT significantly increased DSB levels in both in vitro and in vivo experiments. A positive linear correlation of CT radiation dose with intracellular DSBs levels was observed in the in vitro study.
由于腹部计算机断层扫描（CT）的辐射剂量相较于其他器官系统可能更高，监测此类检查的辐射暴露尤为重要。
评估腹部增强CT（CE-CT）对外周血淋巴细胞中DNA双链断裂（DSB）水平的影响。
本研究分两部分进行：（i）体外研究：将12名志愿者的静脉血样本分为四组。A组样本未接受辐射暴露，而B、C、D组分别接受一次CT扫描，辐射剂量相当于腹部CE-CT扫描的1 - 3倍；（ii）体内研究：对30例患者在CT检查前及检查后5分钟采集血液。分离淋巴细胞并通过γ-H2AX蛋白免疫荧光染色。采用方差分析或配对t检验比较DSB水平。使用Pearson相关分析分析辐射剂量与γ-H2AX焦点增加之间的关系。
在体外研究中，B、C、D组的DSB水平分别比A组高49.4%、96.6%和149.4%（均P < 0.001）。四个亚组的辐射剂量与DSB水平呈线性相关（P < 0.001）。在体内研究中，CT检查后DSB水平升高了43.5%（P < 0.001）。
腹部CE-CT在体外和体内实验中均显著增加了DSB水平。在体外研究中观察到CT辐射剂量与细胞内DSB水平呈正线性相关。
