CT灌注成像联合CT血管成像时头颈部CT血管成像扫描延长时间的初步研究

Preliminary Study of the Scan-delay-time During the Combined Examation of CT Perfusion and CT Angiography After Contrast Media Administration in Cerebral and Cervical CT Angiography

目的探讨应用脑CT灌注峰值时间来预测头颈部CT血管成像(CTA)检查扫描延迟时间的可行性。方法回顾性分析80例头颈部CTA检查患者,按随机数字表随机分为A组(40例,采取经验法选取延时20s扫描)和B组(40例,采取CTP-CTA联合扫描技术),测量左侧大脑中动脉M1段近端和上矢状窦,C4椎体水平左侧颈总动脉和颈内静脉的CT值,并计算同层动静脉CT值差。结果 (1)B组较A组头颈部动脉CT值高(P<0.05),同层动静脉对比度较A组清楚。(2)B组扫描所采集的数据进行重建后均得到满意的头颈部血管图像;A组扫描所采集的数据进行重建后得到头颈部血管图像,其中3例(7.5%)因扫描时间过早、5例(12.5%)因扫描时间过晚而致头颈部血管图像显示不佳。结论 64排螺旋CT头颈部CTA联合应用脑CTP检查中,通过测量脑CT灌注峰值时间预测头颈部CTA检查扫描延迟时间是保障头颈部CTA检查成功的一种较好的方法 。

Objective To discuss the feasibility of the time to peak of cerebral CT perfusion （CTP） in predicting the scan-delay-time after contrast media administration in cerebral and cervical CT angiography （CTA）.Methods Retrospective Analysis was performed in eighty patients who had been examined with cerebral and cervical CTA,they were divided randomly into two groups.Group A：40 patients were performed by the method of experience of 20 seconds as scan-delay-time.Group B：the other 40 patients were examined with the combination scanning technology of CTP-CTA.They were all measured with enhancement value of CT in the M1 segment of left middle cerebral artery、superior sagittal sinus 、left common carotid artery adjacent to the fourth cervical vertebrace and internal jugular vein,and then calculate the difference between the arterys and the veins in the same layer.Statistical significance was determined with t test.Results （1）The enhancement value of CT in the cerebral and cervical artery vessels and the resolving power between the arterys and the veins in the same layer of group B were higher than that in group A.（2）Group B whose cerebral and cervical artery vessels rescontructed from the raw CT data set showed clearly;There were an advance in 3 cases（7.5%）,a delay in 5 cases （12.5%）in group A whose cerebral and cervical artery vessels rescontructed from the raw CT data set didn’t show clearly.Conclusion It＇s a satisfactory method based on successful cerebral and cervical CTA study to take the time to peak in CT perfusion as the scan-delay-time during the combined examination of CTP and CTA with 64-detector spiral CT.