心率波动对16层CT冠脉成像图像质量的影响及对策(心脏体模模拟实验)  

Influence of Fluctuation of Heart Rate on Image Quality of 16-slice Spiral CT Coronary Angiography and Optimization of Scanning Parameters:Cardiac Phantom Study

作　　者：罗银灯[1] 赵建农[1] 李杰[1] 谢微波[1] 曹新山[1] 吴伟[1] 敬永勇[1] 沈霞[1] 廖静敏 陈垦 

机构地区：[1]重庆医科大学附属第二医院放射科,重庆400010 [2]美国通用电气中国医疗集团

出　　处：《实用放射学杂志》2007年第12期1698-1702,共5页Journal of Practical Radiology

基　　金：重庆市自然科学基金资助项目(CSIC;2006BB5277)

摘　　要：目的研究心率波动对16层螺旋CT冠状动脉成像质量的影响及心率波动情况下最佳扫描条件。方法采用GELight-Speed16层螺旋CT,以心脏冠脉扫描模式对心脏体模进行扫描。心率设置为以60次/min、85次/min为中心上下波动2组,每组分别设置波幅为2.5次/min、5次/min和10次/min各3小组,分别对6组心率波动情况下的心脏体模以心脏冠脉扫描模式进行扫描,所有扫描数据在R-R间期5%、15%、25%、35%、45%、55%、65%、75%、85%、95%相位分别进行单扇区(Segment)、双扇区(Burst-2)和四扇区重建(Burst-4)。重建数据传至AW4.1工作站后处理成像。后处理方法采用容积再现(VR)、多平面重组(MPR)模式。由1名高年资医师和1名技师分别对不同重组图像进行评分。统计学处理采用析因分析。结果(1)方差分析显示,总模型具有显著意义(F=22.58,P<0.0001),各变量(心率、波幅、算法和相位)具有显著意义,均对冠状动脉成像质量有影响;(2)不同心率之间比较:心率为60次/min者图像质量评分均数显著高于心率为85次/min者(P<0.05);(3)不同波动范围之间比较:波幅为2.5次/min和5次/min者,图像质量评分均数高于波幅为10次/min者(P<0.05),但波幅为2.5次/min和5次/min无显著差异(P>0.05);(4)不同重建算法之间比较:算法为Burst-4和Burst-2者图像质量评分均数显著高于算法为Segment(P<0.05),但Burst-4和Burst-2之间无显著差异(P>0.05);(5)不同相位之间比较:相位为45%,95%显著高于其他相位(P<0.05),但上述二者相位之间无显著差异(P>0.05)。相位为15%者,图像质量最差。结论新型心脏动态体模评价心率波动对16层螺旋CT冠状动脉成像质量的影响及心率波动情况下最佳扫描条件分析,能够为临床应用和基础研究提供帮助。Objective To study the influence of fluctuation of heart rate on image quality of 16 -slice spiral CT coronary angiography and optimization of scanning parameters. Methods An adjustable pulsating cardiac phantom containing predetermined simulated coronary arteries was scanned using a 16 -slice spiral CT（ GE LightSpeed 16 ） with cardiac pulsating rates at 60 and 85 beats per minute （ bpm ） and fluctuation amplitude as 2.5, 5 and 10 bpm respectively. The raw data were reconstructed using one - sector （ Snapshot segment ） , two - sector （ burst - 2） and four - sector （ burst - 4 ） reconstruction algorithm at 5% - 95% of the R - R interval with an increment of 10%. Reconstruction images were transmitted to workstation （ ADW4.1 ） and post - processed using a pattern of volume rendering （ VR） and multi - planar reformation I MPR}. According to the same evaluation standard of reformatted image, the image quality was scored by a radiologist and a technician. The correlation between heart rate （ HR） , fluctuation amplitude of HR, reconstruction algorithm, phase（ R - R interval（and the score of image quality were analyzed. Results ANOVA suggests that all variables including HR, fluctuation amplitude of HR, reconstruction algorithm, phase （ R - R interval） had significant influence on the image quality score. The average score in the 60 bpm groups was much higher than that in the 85 bpm groups （ P 〈 0.05 ） . The average score in the groups （ fluctuation amplitude of 2.5 bpm and 5 bpm） was higher than that in the groups （fluctuation amplitude of 10 bpm） （ P 〈 0.05 ） , while there was no significant difference between the former two groups （ P 〉0. 05 ） The average score of the two - sector and four - sector reconstruction algorithm groups was significantly higher than that in the one - sector reconstruction alg - orithm groups （ P 〈 0. 05 ）, while there was no significant difference between the former two groups （ P 〉 0. 05 ）. The average scores in

关 键 词：心脏 冠状动脉 体层摄影术 X线计算机 体模 图像质量 

分 类 号：R322.11[医药卫生—人体解剖和组织胚胎学] R322.121[医药卫生—基础医学]