不同扫描时间点、心输出量、心率、冠状动脉狭窄程度对冠状动脉管腔内密度衰减梯度的影响  

Effects of Scan Timepoints,Cardiac Output,Heart Rate and Coronary Artery Stenosis Severity on Intracoronary Transluminal Attenuation Gradient

作　　者：李娇娇[1] 张斌[1] 刘迪[1] 李传贵[1] 李晓东[1] 陈静[1] LI Jiao-jiao;ZHANG Bin;LIU Di;LI Chuan-gui;LI Xiao-dong;CHEN Jing(Department of MRI,the First Affiliated Hospital of Hebei North University,Zhangjiakou 075000,China)

机构地区：[1]河北北方学院附属第一医院影像科,河北张家口075000

出　　处：《南昌大学学报（医学版）》2017年第6期40-44,共5页Journal of Nanchang University：Medical Sciences

基　　金：张家口市科技攻关计划(1521094D)

摘　　要：目的评估对比剂注射后不同扫描时间点、不同心输出量、心率、冠状动脉狭窄程度对管腔内密度衰减梯度(tansluminal attenuation gradient,TAG)的影响。方法采用对比剂流量体模和狭窄程度为0%(正常组)和75%(病变组)的两种体模。采用320排CT进行扫描检查。心率分别设置为60、70次·min^(-1),心输出量分别设置为2.0L·min^(-1)和4.5L·min^(-1)。扫描重复时间以0.5s为间隔直至40s(心输出量为2.0L·min^(-1))和25s(心输出量为4.5L·min^(-1))。在相同层面测量CT值,在不同的扫描时间点计算时间密度曲线(time-density-curve,TDC)和TAG值。结果不同的扫描时间点,正常组TAG值的变异较病变组小(心输出量为2.0L·min^(-1)和4.5L·min^(-1));在病变组,与心输出量为2.0L·min^(-1)相比,心输出量4.5L·min^(-1)的TAG值曲线随着不同扫描时间点逐渐改变。结论不论正常组还是病变组,不同扫描时间和心输出量可影响TAG值。Objective To evaluate the effects of different scan timepoints,cardiac output(CO),heart rate and coronary artery stenosis severity on intracoronary transluminal attenuation gradient(TAG).Methods The 320-detector row volume scan was performed using a contrast medium(CM)flow phantom and two types of simulated coronary artery stenosis:0%(normal group)and 75%(lesion group).Heart rate was set at 60 and 70 beats·min-1,and CO at 2.0 and 4.5 L·min-1.The acquisition time repeated at 0.5 s intervals for 40 and 25 s at CO of 2.0 and 4.5 L·min-1.The CT number was measured on the same slice level,and the time-density-curve(TDC)and TAG were calculated at different timepoints.Results At CO of 2.0 and 4.5 L·min-1,TAG exhibited smaller variation at 75%stenosis than at 0%stenosis at each timepoint.In lesion group,compared with CO of 2.0 L·min-1,TAG curve gradually changed with time at CO of 4.5 L·min-1.Conclusion The TAG is affected by different scan timepoints and CO.

关 键 词：管腔内密度衰减梯度 扫描时间点 心输出量 对比剂流量体模 计算机体层成像 

分 类 号：R814.42[医药卫生—影像医学与核医学] R543.3[医药卫生—放射医学]