双定位像结合DoseRight技术降低外伤儿童胸腹部CT检查辐射剂量的可行性研究

目的探讨采用正侧位定位像结合DoseRight技术进一步降低外伤儿童胸腹部CT检查辐射剂量的可行性。方法前瞻性连续搜集行胸腹部CT检查的0~16岁外伤患儿207例,随机分配到实验组和对照组,实验组采用胸腹部正侧位定位像定位扫描,对照组只采用正位定位像定位扫描,两组患儿均采用DoseRight技术。记录患儿的CTDIVOL及DLP并对比分析,然后对胸腹部CT图像质量进行主观及客观评价。结果实验组患儿胸部及腹部平均DLP较对照组分别降低22.8%和24.1%,差异具有统计学意义(t=-5.7,-5.9;P﹤0.05)。右侧胸大肌处实验组SD值高于对照组而SNR低于对照组,差异有统计学意义(t=4.84,-4.96;P﹤0.01);第5腰椎椎旁肌肉区SD值高于对照组而SNR低于对照组,差异有统计学意义(t=3.93,-3.86;P﹤0.01);其余兴趣区在SD及SNR的差异无统计学意义。实验组和对照组患儿胸腹部图像质量的主观评分差异无统计学意义。结论双定位像结合DoseRight技术能够降低外伤儿童胸腹部CT检查的辐射剂量并保证图像质量,值得应用推广。

Feasibility Study on Reducing Radiation Dose of Thoracic and Abdominal CT Examination in Traumatic Children by Dual Scout Image and DoseRight Technology

Objective To explore the feasibility of further reducing radiation dose of thoracic and abdominal CT examination in traumatic children by using anteroposterior and lateral scout image combined with DoseRight technique.Methods A total of 207 traumatic children aged 0-16 were enrolled prospectively,and divided into test group and control group randomly.Control group underwent a scan protocol with lateral scout scan combined with DoseRight technology,while anteroposterior and lateral scout scan combined with DoseRight technology were performed in test group.CTDIVOL and DLP were recorded and compared among the groups;subjective and objective evaluation of the image quality was made.Results The average DLP in the chest and abdomen of the test group was 22.8%and 24.1%lower than that of the control group.The difference was statistically significant(t=-5.7,-5.9,P﹤0.05).At the right pectoralis major muscle area,SD value of the test group was higher than that of the control group,while SNR was lower than that of the control group(t=4.84,-4.96,P﹤0.01).In the fifth lumbar paravertebral muscle area,SD value of the test group was higher than that of the control group,while SNR was lower than that of the control group(t=3.93,-3.86,P﹤0.01).There was no significant difference in SD and SNR between the other regions of interest.Conclusion Dual positioning image combined with DoseRight technology can reduce radiation dose and ensure image quality in CT examination of thorax and abdomen of traumatic children.It is worthy of application and promotion.