【摘要】 目的:探讨时相预览法在16层CT冠状动脉成像时相选择中的价值。方法:将52例疑冠心病的患者根据心率分为二组:第一组心率≤70次/min 32例,第二组心率>70次/min 20例,进行16层CT冠状动脉扫描,采用回顾性心电门控、0.42s螺旋扫描、0.75mm准直器宽度。选取增强扫描图像的右冠脉中部层面,运用时相预览序列预览R-R心动周期0%~100%的21幅图像(间隔5%),选择显示左、右冠脉最清晰的一幅,记录其时相。对第一组采用单扇区重建算法,对第二组采用双扇区重建算法,应用原始数据重建最佳时相的薄层图像,再进行MIP、MPR、CPR、VR重建。结果:第一组单扇区重建的最佳时相为55%~65%R-R间期。第二组双扇区重建的最佳时相为60%~65%R-R间期(12/20),其次是35%~40%R-R间期(5/20)和70%~75%R-R间期(3/20)。结论:运用时相预览序列优选重建时相可以明显提高工作效率,16层CT冠状动脉成像的最佳重建时相多位于55%~65%R-R间期。更多还原

【Abstract】 Objective:To assess the clinical value of the phase previewing in16-slice spiral CT coronary angiography.Methods:52 patients who were suspected to coronary artery disease were classified into two groups according to heart rate(Group 1≤70bpm and Group 2>70bpm),Group 1 has 32 patients and group 2 has 20 patients.52 patients were studied with 16-slice spiral CT(retrospectively ECG-gating;0.42s rotation;0.75mm collimating apparatus width).Choosing central deck of right coronary artery in enhancement scanning images,previewing 21 images at 0%～100% of the cardiocycle in increments of 5% by the phase previewing, selecting the most clear image of left and right coronary artery,and recording the phase.Group 1 and group 2 was respectively applied by two-sector reconstruction algorithm and single-sector reconstruction algorithm.Raw data were reconstructed with thin images at the best phase.All images were reconstructed in the mode of maximum intensity projection(MIP),multi-plane reformation(MPR),curved planar reformation(CPR) and volume rendering(VR).Image quality of two groups was assessed for each coronary as able and unable to be diagnosed.Results:The best phase of group 1 is 55%～65% R-R phases,the best phase of group 2 is 60%～65% R-R phases(12/20),the second phase is 35%～40% R-R phases(5/20)and 70%～75% R-R phases(3/20).Conclusion:The previewing phase optimization can raise work efficiency,and the best reconstructed phase of 16-slice spiral, CT coronary angiography is commonly 55%～65% R-R intervals.更多还原