依儿童年龄设置胸部管电压优化辐射剂量和图像质量的前瞻性临床研究

Children Age Dependent Chest Tube Voltage Settings for Optimizing Radiation Dose and Image Quality: A Prospective Clinical Study

目的探讨依儿童年龄设置DR胸部管电压优化儿童辐射剂量和图像质量的可行性。方法将2008年1月至2010年12月在新疆医科大学第一附属医院就诊的0至14岁儿童分成0～、1～、3～、7～、11～14岁五个年龄段,每个年龄段再采用计算机随机分成优化组与对照组进行DR摄影。优化组根据年龄设置不同千伏值进行自动控制曝光DR摄影,对照组采用常规千伏值进行自动控制曝光DR摄影。辐射剂量计量用剂量面积乘积(DAP),图像质量用可视化分级分析评分(VGAS)。采用SPSS 17.0软件进行统计分析。结果最初纳入2 450例受试儿童,排除因严重基础疾病而导致某些解剖特征不能显示者35例(1.43%)后,最终纳入2 415例儿童胸部正位图像进行分析,其中优化组1 202例,对照组1 213例。结果显示:优化组DAP均值小于对照组(t=–4.967,P=0.008),而VGAS均值大于对照组(t=23.738,P=0.000)。结论依儿童年龄设置DR胸部管电压能降低儿童辐射剂量,同时改善图像质量。

Objective To explore the feasibility of children age dependent chest tube voltage settings for optimizing radiation dose and image quality in digital radiography （DR）. Methods Children aged 0 to 14 who visited the First Affili- ated Hospital of Xinjiang Medical University from January, 2008 to December, 2010, were divided into the following 5 age groups： 0-, 1-, 3-, 7-, and 11-14-year-old, and each group was then randomly assigned to the optimization and control groups to take DR by computer. DR in automatic exposure control with different tube voltage depending on children age; the control group： DR in automatic exposure control with conventional fixed tube voltage. The dose area product （DAP） was adopted for the measurement of radiation dose, while the visual grading analysis score （VGAS） was for image quality. Then SPSS 17.0 was applied for statistical analysis. Results A total of 2 450 children were initially included. Finally there were 2 415 children included in the anteroposterior chest image in this study, and the other 35 children were excluded for their anatomical characteristics could not be showed due to serious primary diseases. There were 1 202 patients in the optimization group and 1 213 patients in the controlled group. The mean DAP in the optimization group was lower than that in the control group with a significant difference （t= -4.967, P=0.008）. The mean VGAS in the optimization group was higher than that in the control group with a significant difference （t= 23.738, P=0.000）. Conclusion Children age dependent tube voltage settings can effectively reduce radiation dose and improve image quality at the same time,