脑CT灌注成像对比剂注射速率与剂量实验研究

目的探讨多层螺旋CT脑灌注成像合适的注射速率及剂量。方法实验采用配伍组设计。处理因素为对比剂注射速率,分别为3、4、5、6、8 m l/s;配伍因素为对比剂注射剂量,分别为0.5、0.75、1、1.25、1.5 m l/kg。25只比格犬随机入组进行灌注成像扫描。所得图像经后处理,测量上矢状窦内对比剂至峰值时间及升高CT值。结果注射速率对上矢状窦至峰值时间有显著性影响。其中5、6 m l/s组上矢状窦至峰值时间与8 m l/s组相比较,无统计学显著性差异;3、4 m l/s组与8 m l/s组相比较,上矢状窦至峰值时间延长。注射剂量对上矢状窦峰时升高CT值有显著性影响。其中1.5、1.25 m l/kg组上矢状窦峰时升高CT值与1 m l/kg组相比较,无统计学显著性差异;0.5、0.75 m l/kg组与1 m l/kg组相比较,上矢状窦峰时升高CT值降低。结论注射速率低至5m l/s或注射剂量低至1 m l/kg时,脑CT灌注成像亦可获得满意效果。

An Experimental Study about Contrast Medium Injection Rate and Dose in Cerebral CT Perfusion Imaging

Objective To investigate the suitable injection rate and dose in multi-slice CT perfusion imaging.Methods Randomized block design was adopted in this study.The treatment factor-contrast medium injection rate was classified into 3,4,5,6 and 8 ml/s;thesubjects were divided into 5 blocks grouped by contrast medium injection dose: 0.5,0.75,1,1.25 and 1.5 ml/kg.25 Beagles wererandomly enrolled to undergo cerebral CT perfusion imaging.After post processing,time to peak(TTP) and rise value(RV) were measured in superior sagital venous.Results Injection rate had a significant effect on TTP of superior sagital venous.There was no significant difference among group 5,6 and 8 ml/s.Compared with 8 ml/s,TTP of superior sagital venous was prolonged when injection rate 3,4 ml/swere adopted.Injection dose had a significant effect on RV of superior sagital venous.There was no significant difference among group 1,1.25 and 1.5 ml/kg.In comparison with 1 ml/kg,RV of superior sagital venous was prolonged when injection dose 0.5 and 0.75 ml/kg were adopted.Conclusion The quality of cerebral CT perfusion imaging is well enough even injection rate as low as 5 ml/s or injection dose as few as 1 ml/kg.