CAJ | 학술논문

目的评价呼吸运动校正技术对于减小肝脏CT灌注成像中时间-密度曲线(TDC)参数测量误差的作用.方法前瞻性应用64层CT扫描仪对25例临床怀疑肝脏病变的患者行肝门部灌注扫描.对门静脉右支主干所在层面进行呼吸运动校正,分别在校正前后门静脉右支主干内选取10个ROI并绘制TDC,记录达峰时间及峰值,计算各例校正前后达峰时间和峰值的平均值、标准差及变异系数.应用两配对样本秩和检验比较校正前后达峰时间和峰值变异系数的差异,应用独立样本t检验比较校正前后峰值均值的差异.结果经呼吸运动校正后门静脉右支主干TDC峰值变异系数的中位数(四分位距)为2.84%(2.10%,4.57%),小于校正前5.19%(3.90%,7.27%),差异有统计学意义(Z=-3.108,P＜0.01).校正后达峰时间变异系数的中位数为2.64%(0.76%,4.41%),亦小于校正前5.23%(3.81%,7.43%),差异有统计学意义(Z=-3.924,P＜0.01).8例门静脉右支主干TDC峰值校正前后差异有统计学意义(P＜0.05),且校正后峰值均大于校正前.结论呼吸运动校正技术可有效减小肝脏CT灌注成像中TDC参数测量的随机误差.
목적 평개호흡운동교정기술대우감소간장CT관주성상중시간-밀도곡선(TDC)삼수측량오차적작용.방법 전첨성응용64층CT소묘의대25례림상부의간장병변적환자행간문부관주소묘.대문정맥우지주간소재층면진행호흡운동교정,분별재교정전후문정맥우지주간내선취10개ROI병회제TDC,기록체봉시간급봉치,계산각례교정전후체봉시간화봉치적평균치、표준차급변이계수.응용량배대양본질화검험비교교정전후체봉시간화봉치변이계수적차이,응용독립양본t검험비교교정전후봉치균치적차이.결과 경호흡운동교정후문정맥우지주간TDC봉치변이계수적중위수(사분위거)위2.84%(2.10%,4.57%),소우교정전5.19%(3.90%,7.27%),차이유통계학의의(Z=-3.108,P＜0.01).교정후체봉시간변이계수적중위수위2.64%(0.76%,4.41%),역소우교정전5.23%(3.81%,7.43%),차이유통계학의의(Z=-3.924,P＜0.01).8례문정맥우지주간TDC봉치교정전후차이유통계학의의(P＜0.05),차교정후봉치균대우교정전.결론 호흡운동교정기술가유효감소간장CT관주성상중TDC삼수측량적수궤오차.
Objective To evaluate the effect of a breath-motion-correction (BMC) technique in reducing measurement error of the time-density curve (TDC) in hepatic CT perfusion imaging.Methods Twenty-five patients with suspected liver diseases underwent hepatic CT perfusion scans.The right branch of portal vein was selected as the anatomy of interest and performed BMC to realign image slices for the TDC according to the rule of minimizing the temporal changes of overall structures.Ten ROIs was selected on the right branch of portal vein to generate 10 TDCs each with and without BMC.The values of peak enhancement and the time-to-peak enhancement for each TDC were measured.The coefficients of variation (CV) of peak enhancement and the time-to-peak enhancement were calculated for each patient with and without BMC.Wilcoxon signed ranks test was used to evaluate the difference between the CV of the two parameters obtained with and without BMC.Independent-samples t test was used to evaluate the difference between the values of peak enhancement obtained with and without BMC. Results The median (quartiles) of CV of peak enhancement with BMC [2.84% (2.10%,4.57%)]was significantly lower than that without BMC [5.19% (3.90%,7.27%)](Z=-3.108,P＜ 0.01).The median (quartiles) of CV of time-to-peak enhancement with BMC [2.64% (0.76%,4.41%)]was significantly lower than that without BMC [5.23% (3.81%,7.43%)](Z=-3.924,P＜0.01).In 8 cases,TDC demonstrated statistically significant higher peak enhancement with BMC (P＜ 0.05).Conclusion By applying the BMC technique we can effectively reduce measurement error for parameters of the TDC in hepatic CT perfusion imaging.