正常大鼠脑CT灌注成像的可重复性研究

目的:评价多层螺旋CT灌注成像对正常大鼠脑血流动力学观测结果的可重复性.方法:分别对10只健康Wistar大鼠间隔2d进行CT灌注扫描,两组原始灌注数据由2名放射科医师分别进行5次后处理得出CBF、CBV和MTT值.分析观察者内和观察者间观测结果的可重复性,以及对同一组研究对象间隔2d两次检查结果的一致性.结果:多层螺旋CT对Wistar大鼠脑所采集的灌注原始数据在观察者内和观察者间观测结果均无统计学差别(P＞0.05),并具有很好的线性(CBF和CBV值)或等级(MTT值)正相关(P＜0.01).对同一组研究对象间隔2d的两次CT灌注成像结果也存在同样好的重复性.结论:多层螺旋CT灌注成像对于Wistar大鼠脑部血流动力学观测具有很高的精密度和准确性,完全适于小型动物模型脑部血流动力学的研究.

Reproducibility of CT Perfusion Imaging in Normal Rat Brain

Objective:To evaluate reproducibility of the cerebral hemodynamic characteristics in normal rat brain by CT perfusion (CTP)imaging.Methods:10 healthy Wistar rats were performed with two cerebral CTP scans at intervals of two days.The images de- rived from dynamic CTP examinations were analyzed five times by two radiologists.The CBV,CBF and MTT values were computed. Reproducibility of observation results were analyzed between intraobserver and interobserver,and the consistency of results were studied at intervals of two days measurements.Results:There were no statistical difference in the both intraobserver observation and interobserver observation(P>0.05).Moreover,regression analyses performed on combined intraobserver and interobserver variability data indicated a strong linear positive relationship in both CBV and CBF values(P<0.01)and a rank positive relationship in the MTT measurements (P<0.01).The reproducibility of two CT perfusion imaging at intervals of two days was also very good.Conclusion:Mutislice CTP pro- vides high precision and accuracy for the measurement of Wistar rat brain hemodynamics,and it is suitable for the brain hemodynamics study of small animal models.