正常兔脑多层螺旋CT灌注及MR灌注成像

Mutislice CT Perfusion Imaging and MRI Perfusion Weighted Imaging in Normal Rabbits Cerebral Hemodynamics

目的:探讨多层螺旋CT及MR在正常兔脑血流动力学测量中的应用。材料和方法:健康新西兰种大白兔15只,行CT平扫后,选择基底节层面及相邻层面,经耳缘静脉途径以0.5ml/s速率注入CT造影剂,同时开始连续50s多层动态扫描;CT造影剂排空后,经耳缘静脉途径快速团注MR造影剂,同时开始连续43s多层动态扫描,经后处理获得CT及MR灌注图像。对感兴趣区测量血流量、血容量及平均通过时间等血流动力学参数,并与小脑的相应值相比进行分析。结果:应用CT灌注可以获得较好图像质量,MR灌注可反映出全兔脑组织的血流动力学状态,CT灌注及MR灌注获得的血流动力学参数相对值之间比较无显著性差异(P>0.05)。结论:多层螺旋CT灌注及MR灌注成像为兔脑血流动力学研究提供了新的无创性手段。

Purpose： To evaluate the application of mutislice CT perfusion imaging（MSCTPI） and MRI perfusion weighted imaging（PWI） in normal rabbits cerebral hemodynamics. Materials and Methods： Routine CT scans were performed in 15 normal New Zealand rabbits, then MSCTPI study was made by selecting the basal ganglia slice and its adjacent slices. The CT contrast material was bolus injected through ear vein in 0.5 ml/s, while multi - layer of dynamic scans were performed for 50 seconds. After the excretion of the CT contrast, the MR contrast material was bolus injected through ear vein rapidly, while multi- layer of dynamic scans were performed for 43 seconds.Cerebral blood flow, cerebral blood volume, mean transit time were measured in the specific region of interest of the brain, which were compared with the value of the cerebellum, and then quantitative analysis was performed.Results： The better image quality could be obtained by MSCTPI. The whole hemodynamic information could be obtained on PWI. There was no significant difference in the relative cerebral hemodynamic parameters among groups performed with MSCTPI and PWI（P 〉 0.05）. Conclusion： MSCTPI and PWI provide new imaging methods for measuring the cerebral hemodynamics in nomal rabbits.