摘要
目的:探讨基于胸围的固定管电流检查在幼儿胸部增强CT中的应用价值。方法:回顾性分析171例胸部增强参考病例的病例资料,建立DW与胸围(CC)的回归方程。依据胸围分为CC≤45 cm、45 cm<CC≤55 cm、55 cm<CC≤65 cm及65 cm<CC≤75 cm四个亚组,统计参考病例各亚组容积CT剂量指数(CTDIvol)上四分位数。前瞻性搜集行胸部增强CT检查的患儿96例,按照随机数字表法将患儿分为对照组和实验组。对照组患儿44例,依照CTDIvol设定管电流;实验组患儿52例,依照体型特异性剂量评估值(SSDE)设定管电流。两组参考辐射剂量均为参考病例CTDIvol上四分位数,对比分析两组患儿的图像质量及辐射剂量。结果:参考病例DW与胸围呈较强正相关(R 2=0.911,P<0.001),其回归方程为DW=2.45+0.25×CC。CTDIvol上四分位数分别为2.22 mGy、2.80 mGy、3.80 mGy、6.33 mGy。对照组及实验组患儿的CTDIvol分别为(4.52±0.94)mGy、(2.91±0.50)mGy,差异有统计学意义(Z=-7.65,P<0.001);对照组及实验组患儿的SSDE DW分别为(6.12±0.88)mGy、(3.87±0.52)mGy,差异有统计学意义(Z=-8.13,P<0.001)。实验组的CTDIvol、SSDE DW较对照组分别降低35.62%(1.61/4.52)、36.76%(2.25/6.12)。图像质量客观评价两组间差异有统计学意义(t=4.12、-3.85、4.71,P<0.001);主观评价及信心评分两组间差异无统计学意义(Z=-1.23、t=0.02,P>0.05)。结论:根据患儿胸围计算SSDE DW并以此设置固定管电流检查在临床实践中具有可行性,在满足图像诊断要求的前提下可降低患儿的辐射剂量。
Objective:To investigate the value of chest circumference-based fixed tube current in chest enhanced CT scan in children.Methods:A retrospective analysis of the data of 171 reference cases of chest enhanced CT was performed to establish the regression equation of DW and chest circumference(CC).Based on the CC,four subgroups were divided:CC≤45cm,45cm<CC≤55cm,55cm<CC≤65cm and 65cm<CC≤75cm,and the upper quartile of volume CT dose index(CTDIvol)was counted for each subgroup of reference cases.A total of 96 children who underwent chest-enhanced CT scan were prospectively collected and divided into control and experimental groups according to the random number table method.Forty-four children in the control group were scanned with the setting of tube current according to CTDIvol,and 52 children in the experimental group were scanned with the setting of tube current according to the size-specific dose estimates(SSDE).The reference radiation dose in both groups was the upper quartile of the CTDIvol of the reference case,and the image quality and radiation dose of the children in both groups were compared and analyzed.Results:There was a strong positive correlation between reference case DW and CC(R 2=0.911,P<0.001),and the regression equation was DW=2.449+0.25×CC.The quartile in CTDIvol were 2.22mGy,2.80mGy,3.80mGy and 6.33mGy,respectively.The CTDIvol of children in the control and the experimental group were(4.52±0.94)mGy and(2.91±0.50)mGy,respectively,with statistically significant differences between groups(Z=-7.65,P<0.001).And the SSDE DW of children in the control and the experimental group were(6.12±0.88)mGy and(3.87±0.52)mGy,respectively,with statistically significant differences between groups(Z=-8.13,P<0.001).CTDIvol and SSDE DW in the experimental group decreased by 35.62%(1.61/4.52)and 36.76%(2.25/6.12),respectively,compared with the control group.The differences between the groups of objective evaluation of image quality were statistically significant(t=4.12,-3.85,4.71,P<0.001).The differences between the groups of subjective evaluation and confidence scores were not statistically significant(Z=-1.23,t=0.02,P>0.05).Conclusion:It is feasible in practice to preset fixed tube current calculated by the SSDE DW according to the chest circumference of the patient,which reduces the radiation dose on children while satisfying the image diagnosis.
作者
张见
张晓军
刘杰
ZHANG Xian;ZHANG Xiao-jun;LIU Jie(Department of Radiology,Children's Hospital of Nanjing Medical University,Nanjing 210000,China)
出处
《放射学实践》
CSCD
北大核心
2023年第1期93-97,共5页
Radiologic Practice
基金
江苏省政府留学基金(JS-2018-137)
江苏省妇幼保健课题(FYX201816)
南京市医学科技发展基金(QRX17169)。
