流速与延迟时间对脑血管SCTA成像的影响

目的：探讨不同流速与延迟时间对脑血管螺旋CT血管造影（SCTA）成象影响。方法：随机选取30例头部增强扫描患者，对每例患者的鞍上池平面分别以2ml/s、3ml/s、4ml/s的流速注对比剂进行同层动态扫描，即小剂量循环试验。收集资料后，利用Time-lapse软件作时间－密度曲线，结果：流速由2ml/s增加到3ml/s及4ml/s时动静脉峰值时间缩短，统计学上有显著性差异。由3ml/s增加到4ml/s时，动静脉峰值强时间缩短不明显，统计学上无显著性差异。结论：小剂量循环试验可作为SCTA检查中的常规步骤，以确定最佳延迟时间。脑血管SCTA扫描流速以3ml/s较合适。

Effect of Flow Rate and Delayed Time on Intracranial Vascular SCTA Imaging

Objective To investigate the effect of contrast material flow rate and delayed time on intracranial vascular spiral computed tomographic angiography(SCTA) imaging.Methods 30 patients were selected randomly who planed to do brain contrast enhanced CT examination.In all 30 patients a plane dynamic test scanning at suprasellar cistern level was preformed with 20ml contrast material at a flow rate of 2ml/s,3ml/s and 4ml/s respectively.A time-densty cure was originated from data collected with the software of Time-Lapse.Results The summit time of most intense enhancement of arteriovena was significantly shortened when the flow rate was increased from 2ml/s to 3ml/s or 4ml/s,and the summit time was shortened without satistically difference when the flow rate was increased from 3ml/s to 4ml/s.Conclusions The circulation time test with a little volume contrast material can become a routine procedure of SCTA examination to determine the best delayed time.The suitable flow rate of intracranial vascular SCTA is 3ml/s.