GE Lightspeed 64排128层螺旋VCT颅、颈联合(CTA)成像技术探讨

Study on imaging parameters of 128-slice spiral CT angiography in intracranial and cervical arteries

目的探讨颅、颈动脉螺旋CT血管造影的最佳增强时相的触发技术及各种后处理技术的应用,以期提高颅、颈动脉三维显示率及病变的检出率。方法(1)选60例健康自愿者,随机分成A、B、C三组,应用SmartPrep软件实时监控,当感兴趣区造影剂浓度达阈值(50HU)后触发增强扫描序列,A组扫描间隔为2秒,B组扫描间隔为3秒,C组扫描间隔为4秒,完成数据采集。评价图象质量,确定最佳扫描间隔时间。(2)80例怀疑颅、颈动脉疾病进行颅、颈动脉CTA检查的患者,扫描后进行最大密度投影(MIP)、曲面重建(CPR)、容积再现技术(VR),评价三维血管的质量,探讨各种后处理技术的应用价值。结果(1)A、B、C三组均能显示颅、颈动脉,B组图象质量最佳,A、B、C三组图象质量差异有统计学意义(P值均〈0.05)。(2)在颅脑血管疾病的诊断中,容积再现技术(VR)三维立体效果好,可以很好的显示血管的走行,最大密度投影(MIP)可以很好的显示血管内部病变。在颈部血管疾病的诊断中,曲面重建(CPR)可以很好的显示血管的狭窄、闭塞、钙化、斑块。结论利用SmartPrep软件实时监控造影剂浓度并及时触发增强扫描技术不受个体差异因素的影响,(尤其是肘静脉注射途径影响因素颇多)。最大密度投影(MIP)、曲面重建(CPR)、容积再现技术(VR)相结合可以获得满意的图像质量。

Objective To explore the application of the bolus-triggered technique and the post-processing technique of MSCTA in intracranial and cervical arteries in order to improve their diagnoses. Methods （1） 60 healthy volunteers were divided into 3 groups randomly, monitored by Smartpred software to trigger the scan when the threshold achieved 50 Hu. The scanning parameters were as follows. Group A： the interval between two scans was 2 seconds. Group B： the interval between two scans were 3 seconds. Group C： the interval between two scans were 4 seconds. To evaluated the imaging quality and to determine the best parameters. （2） 80 patients with suspected intracranial and cervical artery diseases underwent the contrast-enhance MSCT. The images were reconstructed by Maximum intensity projection（MIP）,curved planar reformat （CPR）,volume rendering （VR） to evaluate three-dimensional reconstruction images and explore the value of CTA reconstruction technique. Results （1） Group A, group B and group C all could show the artery, and the images of group B are the best. There were statistical significant difference in them. （p〈0.05） （2） In the diagnosis of intracranial artery diseases VR could show good there-dimensional effects, changes of the vessel and could display the shift direction of the vessel; MIP could show the changes inside the vessel; in the diagnosis of cervical artery diseases, CPR could show vessel stenosis, occlusion, calcification and plaque. Conclusion There are no individual facts that affect the image if we use the Smartprep software technique （especially injecting by the elbow vein）.