基于定位像最大左右径的管电压结合低对比剂在儿童腹部增强CT检查中的价值研究  

Study on the value of tube voltage based on the MLAT of location images combined with low contrast agent in contrast-enhanced CT examination on abdomen of children

作　　者：张见 张晓军 王颖 ZHANG Jian;ZHANG Xiao-jun;WANG Ying(Department of Radiology,Children’s Hospital of Nanjing Medical Universit,Nanjing 210000,China)

机构地区：[1]南京医科大学附属儿童医院放射科,江苏南京210000

出　　处：《中国医学装备》2022年第4期43-48,共6页China Medical Equipment

基　　金：江苏省政府留学基金(JS-2018-137)“儿童神经母细胞瘤的多模态分期及预后”;江苏省妇幼保健课题(FYX201816)“3DMRCP及DTI在新生儿胆汁淤积性黄疸早期诊断中的应用价值”;南京市医学科技发展基金(QRX17169)“儿童1型糖尿病功能成像”。

摘　　要：目的:探讨基于定位像最大左右径(MLAT)设置的管电压结合低对比剂用量在儿童腹部增强CT检查中的应用价值。方法:前瞻性收集医院行全腹部CT平扫加增强检查的180例患儿,按照检查时间顺序依次分为常规组、观察组及低对比剂组,每组60例。3组患儿依照年龄及腹部MLAT的不同而采用不同的管电压以及对比剂用量:常规组管电压依照不同年龄分别使用80 kV、100 kV和120 kV;对比剂用量分别为2.0 ml/kg、1.6 ml/kg和1.4 ml/kg。观察组依据患儿正位定位像MLAT的不同采取不同的管电压为80 kV、100 kV和120 kV;对比剂用量同常规组。低对比剂组管电压使用同观察组;对比剂用量分别为1.6 ml/kg、1.2 ml/kg和1.0 ml/kg。比较3组患儿的图像质量及辐射剂量。结果:3组患儿的图像均能满足诊断要求,图像客观评价动脉期及静脉期肝脏及腹主动脉CT值、信噪比(SNR)及对比噪声比(CNR)的差异均有统计学意义(动脉期:F_(肝脏)=9.76,F=5.19,F=6.07;F_(腹主动脉)=9.02,F=11.90,F=7.06;静脉期:F_(肝脏)=14.67,F=15.19,F=8.09;F_(腹主动脉)=11.33,F=12.97,F=16.73;P<0.05)。3组图像质量主观评分及信心评分之间的差异均无统计学意义(H=1.50,H=1.82;P>0.05)。3组患儿的辐射剂量容积CT剂量指数(CTDI_(VOL))、基于有效直径与水当量直径的体型特异性剂量估算值(SSDEDe)、(SSDE_(Dw))及对比剂摄入量的差异均有统计学意义(H=7.33,H=8.91,H=7.02,H=5.88;P<0.01)。观察组和低对比剂组的CTDIVOL较常规组分别降低33.62%和29.66%;SSDEDe较常规组分别降低30.58%和28.90%;SSDEDw较常规组分别降低30.67%和29.10%。低对比剂组的对比剂摄入量较常规组和观察组分别减少26.86%和26.62%。结论:基于定位像腹部MLAT设置的管电压结合低对比剂用量,在降低患儿辐射剂量及对比剂诱发肾病的潜在风险的前提下,其图像质量仍能够满足临床诊断要求,在儿童腹部增强CT检查中具有可行性。Objective:To explore the applications value of the combination of tube voltage,which based on the installation of max lateral(MLAT)of localization images,and the dosage of low contrast agent in the contrast-enhanced computed tomography(CT)examination on abdomens of children.Methods:A total of 180 children who underwent CT plain scan combined with contrast-enhanced examination on whole abdomen were prospectively collected and they were successively divided into routine group,observation group and low contrast agent group according to the time of examination,with 60 cases in each group.Different tube voltage and the dosage of contrast agent were adopted according to the differences of the age and MLAT of abdomen of 3 groups.In the routine group,the tube voltage adopted respectively 80kV,100kV and 120kV according to different ages,and the dosages of contrast agent were respectively 2.0ml/kg,1.6ml/kg and 1.4ml/kg.In observation group,the different tube voltages(80kV,100kV and 120vK)were respectively adopted according to the MLAT of location image of positive positions of children,and the dosage of contrast agent was same to routine group.The use of tube voltage of low contrast agent group was same to that of observation group,and the use of contrast agent were respectively 1.6 ml/kg,1.2 ml/kg and 1.0 ml/kg.And then,the image quality and radiation doses of three groups were further compared.Results:The images of 3 groups could meet the requirements of diagnosis,and the differences of images among 3 groups were significant in objectively evaluating CT value,signal-noise ratio(SNR)and contrast noise ratio(CNR)of liver and abdominal aorta in arterial phase and venous phase(arterial phase:Fliver=9.76,F=5.19,F=6.07,F_(abdominal aorta)=9.02,F=11.90,F=7.06,venous phase:F_(liver)=14.67,F=15.19,F=8.09,F_(abdominal aorta)=11.33,F=12.97,F=16.73,P<0.05).But there were no statistically significance in subjective scoring and confidence scoring on image quality among 3 groups(H=1.50,H=1.82,P>0.05).The differences of CT dose index of

关 键 词：管电压 对比剂 腹部 X射线CT 辐射剂量 定位像 

分 类 号：R814.42[医药卫生—影像医学与核医学]