16层螺旋CT冠状动脉成像的临床价值

目的:探讨16层螺旋CT冠状动脉成像的临床应用价值.方法:采用GE LightSpeed 16层螺旋CT,对36例可疑冠心病患者行CT冠状动脉成像检查,按照心率不同分为Agt(≤65次/min)14例、B组(66-70次/min)12例和C组(71～75次/min)10例3组,前一组采用单扇区重建,后两组采用双扇区重建,重建时相预设为75%R-R间期,扫描完成后分别重建45%、55%、65%和 85%R-R间期图像.重建数据传至AW4.1工作站后处理成像.后处理方法采用最大强度投影(Maximum intensity pmjection,MIP)、容积再现(Volume rendering,VR)、多平面重组(Multi-planar reformation,MPR)等模式,分别获取冠状动脉的各种重组图像并分析冠状动脉主要分支的显示率.统计学处理采用卡方检验.结果:A组冠状动脉的主要分支包括右冠状动脉、左冠状动脉主干、前降支和左旋支的显示率均为100%;B组其显示率分别为91.67%、100%、100%和91.67%;C组其显示率分别为80%、100%、90%和70%.3组间差异无统计学意义(P>0.05).左冠状动脉主干和前降支在75%R-R间期显示最佳,左旋支在55%显示最佳,右冠状动脉在65%R-R间期显示最佳.各重建相位间显示差异无统计学意义(P>0.05).结论:作为无创性的检查手段,16层螺旋CT能充分显示冠脉主干及其主要分支的正常解剖以及病变特征.随着CT技术的发展和临床应用的增多,多层螺旋CT冠脉成像必将发挥重要作用.

Clinical application of 16-slice spiral CT coronary angiography

Objective:To study the clinical value of 16-slice spiral CT coronary angiography. Methods: CT coronary angiography was performed on 36 patients with suspected coronary heart disease with the use of 16-slice spiral CT (LightSpeed,GE Healthcare, USA). They were divided into three groups according to their heart rates, group A with heart rate≤65bpm, group B with heart rate from 66bpm to 70bpm, and group C with heart rate from 71bpm to 75bpm. One-sector reconstruction algorithm was used in group A; two-sector reconstruction algorithm was used in group B and group C. Reconstruction phases were placed at 75% R-R interval in advance and at 45% ,55% ,65% and 85% R-R interval after scanning. Reconstruction images were transmitted to workstation (ADW4.1) and post-processed with the use of a pattern of maximum intensity projection (MIP), volume rendering (VR) and multi-planar reformation (MPR). The demonstrated coronary artery branches were calculated and analyzed. Results: The demonstrating rate of main branches of coronary artery , including the right coronary artery(RCA), the left main coronary artery(LM), the left anterior descending branch (LAD) and the left circumflex branch (LCX )was 100% in group A, those of group B were 91.67%, 100%, 100%, and 91.67%,respectively, and 80%, 100% ,90% ,and 70%, respectively in group C. The optimal reconstruction phase for LM and LAD was at 75%R-R interval, LCX at 55% R-R interval, RCA at 65% R-R interval. Conclusion: As a noninvasive technique, 16-slice spiral CT coronary angiography could demonstrate the anatomy of coronary arteries and their main branches and the characteristics of coronary artery diseases. With the development of CT technology and its increase of clinical application, multi-slice spiral CT would play a great role in coronary artery imaging.