不同输入参考动脉对CT灌注图像参数的影响研究

目的：探讨头CT灌注成像图像后处理中输入不同参考动脉对灌注参数的影响。资料与方法：收集35例行头CT平扫及头CT灌注成像的患者，包括8例正常者，27例单侧大脑中动脉区缺血患者，行常规头CT平扫后进行CT灌注成像，在图像后处理中，每例患者均进行3次图像后处理，3次后处理分别选择大脑前动脉、健侧（缺血患者）或左侧（正常组）大脑中动脉及患侧（缺血患者） 或右侧（正常组）大脑中动脉作为输入动脉，3次均选择上矢状窦作为输出静脉，分别在双侧皮质区绘制感兴趣区（ROI），记录3次生成的灌注图像各ROI的血流量值（CBF）、血容量值（CBV）及平均通过时间值（MTT），所得3组数据进行单因素方差分析。结果：在正常者中，3次后处理所获得的各参数值之间没有统计学差异（P>0.05），而在单侧大脑中动脉缺血的患者中，3次后处理所获得CBF及MTT值之间具有统计学差异（P<0.05），CBV值之间没有统计学差异（P>0.05）。结论：进行头CT灌注成像的后处理，在正常者中可以选择脑内任意较大的动脉，而在单侧大脑中动脉缺血患者中要尽量选择正常的大脑前动脉作为输入动脉。

The study of the influence of different input artery on CT perfusion parameters

Objective: To explore the effect of perfusion parameters of input different artery in the reconstruction of CT perfusion imaging. Materials and Methods: Thirty-five patients including 8 normals, 27 unilateral middle cerebral artery(MCA) stenosis patients were collected perform normal brain CT scan and CT perfusion imaging. They all had brain CT perfusion imaging after normal brain CT scan. In the reconstruction of cerebral CT perfusion, every data was reconstructed 3 times and the anterior cerebral artery(ACA) were chosen, uninjured side(stroke patients) or left(normal) MCA and injured side(stroke patients) or right(normal) MCA to be input artery respectively, and choosed superior sagittal sinus to be output vein. Drawed region of interest(ROI) in the cortical area of each side and recorded cerebral blood flow(CBF), cerebral blood volume(CBV), and mean transit time(MTT) of ROI. Three data was analysed with one-factor analysis of variance. Results: There is no statistic difference among all parameters in the normals. Otherwise there is statistic difference among all CBF and MTT in unilateral stroke in MCA patients, and there is no statistic difference among CBV. Conclusion: In the reconstruction of cerebral CT perfusion, any large artery can be chosen as input artery in normals, otherwise in the unilateral MCA stenosis patients, the normal ACA should be chosen as input artery.