摘要
目的评估第二代双层探测器光谱CT(DLCT)在100 kVp低辐射剂量条件下CT门静脉成像(CTPV)的图像质量。方法收集2023年5月—2024年3月在武汉亚心总医院使用DLCT扫描的腹部增强检查110例[男54例,女56例,(57.47±15.07)岁]。采用随机法分为对照组A组120 kVp(n=50)与研究组B组100 kVp(n=60)。将A组CTPV的原始数据重建为常规混合能量图像(CI),B组CTPV的原始数据重建为CI和40~80 keV(间隔10 keV)的虚拟单能量图像(VMI)。测量所有图像的门静脉主干及左右分支的CT值、标准差(SD)、信噪比(SNR)和对比信噪比(CNR),并由两位影像科医生进行主观图像质量评分。结果A组有效辐射剂量(ED)为(4.05±1.23)mSv,B组为(1.92±0.21)mSv,辐射剂量降低了52.59%。B组40、50、60 keV VMI的门静脉及其分支平均CT值、SNR和CNR均高于A、B两组的CI(所有P<0.0001),其中40和50 keV VMI的SNR和CNR最高,两者间差异无显著性(P<0.05)。40和50 keV VMI的SD和A组处于相同的水平(P>0.05),60~80 keV VMI的SD显著低于A组(P<0.05)。主观图像质量评估显示50 keV VMI评分为5分(最佳)的占比最高(75%),主观一致性较好(所有Kappa值>0.8)。结论采用100 kVp DLCT的50 keV VMI,和120 kVp的常规图像相比,降低辐射剂量的同时,可获得满足临床诊断需求的图像质量。
Objective To evaluate the image quality of CT portal venography(CTPV)under low radiation dose conditions at 100 kVp using a second-generation dual-layer detector spectral CT(DLCT).Methods A total of 110 patients[54 men,56 women,mean age:(57.47±15.07)years]underwent abdominal contrast-enhanced DLCT from May 2023 to March 2024.The patients were randomly divided into a control group(120 kVp,n=50)and a study group(100 kVp,n=60).The original CTPV data from the control group were reconstructed into conventional mixed-energy images(CI),while the data from the study group were reconstructed into CI and virtual monoenergetic images(VMI)at 40-80 keV intervals(10 keV steps).The CT values,standard deviation(SD),signal-to-noise ratio(SNR),and contrast-to-noise ratio(CNR)of the main portal vein and its left and right branches were measured.Subjective image quality was assessed by two radiologists.Results The effective radiation dose(ED)for the study group[(1.92±0.21)mSv]was 52.59%lower than that of control group[(4.05±1.23)mSv].The average CT values,SNR,and CNR of the portal vein and its branches in the 40,50,and 60 keV VMIs of the study group were significantly higher than those in the CIs of both groups(all P<0.0001),with the highest SNR and CNR observed at 40 and 50 keV VMIs.There was no significant difference in the SNR and CNR between 40 and 50 keV VMIs(P<0.05).The SD of 40 and 50 keV VMIs in the study group was comparable to that of control(P>0.05)whereas the SD of 60-80 keV VMIs was significantly lower than that of control(P<0.05).Subjective image quality assessment showed that 50 keV VMI had the highest proportion of scores rated as 5(best)at 75%with good interobserver agreement(allκ>0.8).Conclusion Using 50 keV VMI with 100 kVp DLCT provides image quality that meets clinical diagnostic requirements while significantly reducing radiation dose compared to conventional images at 120 kVp.
作者
陈诚
陈险峰
桂绅
钟志林
陈翰林
崔敏
邓文俊
CHEN Cheng;CHEN Xianfeng;GUI Shen;ZHONG Zhilin;CHEN Hanlin;CUI Min;DENG Wenjun(Department of Radiology,Wuhan Asia General Hospital,Hubei 430056,China)
出处
《影像诊断与介入放射学》
2024年第3期185-192,共8页
Diagnostic Imaging & Interventional Radiology
作者简介
通信作者:陈险峰,Email:1921599697@qq.com。
