64排螺旋CT头颈联合CTA成像中自动跟踪与手动触发技术的应用

目的：探讨自动跟踪与手动触发技术在Philips 64排螺旋CT对头颈联合CTA成像图像质量的影响。方法：将接受头颈联合CTA检查的100例患者按照随机数字表法分为A组和B组各50例。A组于监控层面主动脉弓层感兴趣区域CT值达阈值（阈值设定为90 HU）后自动跟踪智能触发扫描。B组在对比剂开始注射后观察监控层主动脉弓层对比剂的增强程度，当观察到对比剂开始进入监控层时按下手动按钮触发扫描。统计分析两组的图像质量、记录监控时间，剔除不成功及显示欠佳的图像，分别测量主动脉弓层、颈总动脉分叉下C5段、颈内动脉C1段、大脑中动脉的平均CT值。结果：B组的图像质量明显优于A组，差异有统计学意义（χ2=6.205，P=0.044）。B组的监控时间（13.32±1.63）s明显少于A组的（14.24±1.73）s，差异有统计学意义（P=0.007）。B组所测得的主动脉弓层平均CT值明显低于A组（P〈0.05），两组的颈总动脉分叉下C5段、颈内动脉C1段、大脑中动脉的平均CT值比较差异均无统计学意义（P〉0.05）。结论：手动触发技术比自动跟踪智能触发技术更易获得满足诊断要求的图像，更省时。

The Application of Automatic Tracking and Manually Trigger Technology in Head and Neck 64-slice Spiral CT Angiograph

Objective：To investigate the effect of image quality between automatic tracking and manually trigger technology in head and neck 64-slice spiral CT angiography.Method：100 patients underwent CT head and neck angiography were randomly divided into the group A and the group B,50 cases in each group.Group A：when the mean CT value of region of interest（ROI） determined in the top of the aortic arch reached the threshold preset value（threshold 90 HU）,the computer started a scanning automatically.Group B：after contrast injection,when the contrast appeared in the top of the aortic arch, the scan was started manually.Analyzed the image quality,recorded the time from contrast injection to scan, excluding the unsuccessful and poor display of images.The mean CT value of the top of the aortic arch,the C5 segment of the carotid bifurcation,the C1 segment of the internal carotid artery and middle cerebral artery were measured.Result：The image quality of group B was better than group A,the difference was statistically significant（χ2=6.205,P=0.044）. The monitoring time in group B was （13.32±1.63）s,it was significantly less than （14.24±1.73）s in group A,the difference was statistically significant（P=0.007）.The average CT value of aortic arch was significantly lower than the group A（P〈0.05）,there were no statistically significant differences in the mean CT value of the C5 segment of the carotid bifurcation,the C1 segment of the internal carotid artery and the middle cerebral artery（P〉0.05）.Conclusion：The satisfactory images can easier obtain using the manually trigger technology than automatic tracking,and save time.