低千伏前门控CTA扫描结合迭代重建技术对CABG术后复查桥血管图像质量的应用价值  

Image qulity study of prospective ECG-triggered and iDose^4 iteration reconstruction in coronary artery bypass grafts

作　　者：朱凯[1] 肖喜刚[1] 唐亮[1] 杜英[1] 郝晓屹[1] 

机构地区：[1]哈尔滨医科大学附属第一医院CT室,黑龙江哈尔滨150001

出　　处：《哈尔滨医科大学学报》2016年第3期254-258,共5页Journal of Harbin Medical University

摘　　要：目的探讨256层螺旋CT低k Vp、i Dose4迭代重建结合前瞻性心电门控技术对冠状动脉搭桥术后桥血管成像质量的影响。方法将85例冠状动脉搭桥术后行CTA复查患者随机分为两组(实验组及对照组)。测量实验组41例(管电压100 k Vp,对比剂碘浓度300 mg I/m L,前门控扫描,i Dose4迭代重建)及对照组44例(管电压120 k Vp,对比剂碘浓度370 mg I/m L,后门控扫描,FBP重建)胸锁关节层面、胸骨角层面以及主动脉根部CT值,并比较两组图像的信噪比(SNR)、对比噪声比(CNR)、主观图像质量评分和辐射剂量。结果 85例患者均成功完成扫描,实验组与对照组主观评分一致性极好,两组间主观评分、各层面动脉CT值、CNR、SNR差异均无统计学差异(P>0.05),实验组与对照组之间有效辐射量分别为(2.67±0.72)m Sv、(18.53±7.18)m Sv(P<0.01),差异有统计学意义,碘摄入总量实验组较对照组降低20%。结论对于心率小于72次/分的冠状动脉搭桥术后患者,运用前瞻性心电门控技术、100 k Vp管电压结合迭代重建技术,在有效地降低辐射剂量及碘摄入总量的同时,所获得图像质量与常规方式扫描无差别。Objective To investigate the impact of iDose^4 iteration reconstruction and prospective ECG-gated scanning in low concentration contrast medium and low radiation dose scanning of computed tomography angiography（ CTA） after coronary artery bypass grafts（ CAGA）.Methods Eighty-five cases were enrolled and randomly divided into two groups： experimental group（ n = 41） and contral group（ n = 44）. CT value in the level of the sternoclavicular joint,the sternal angle and root of aorta of the experimental group（ 100 k Vp,300 mg I / m L,prospective ECG-gated scanning,iDose^4） and the contral group（ 120 k Vp,370 mg I/m L,retrospective ECG-gated scanning,FBP） were detected. Image quality was scored subjectively,SNR,CNR and effective radiation dose of the two groups were compared. Results There was no sig-nificant difference between experimental group and contral group on image quality（ P 0. 05）as well as the CT values,SNR,CNR. The effective radiation dose for the experimental group and contral group was（ 2. 67 ± 0. 72） mS v,（ 18. 53 ± 7. 18） mS v,respectively,and there was significant difference between the two groups（ P 0. 01）. Compared with the contral group the total amount of iodine decreased 20. 0% in the experimental group. Conclusion To the patients whose heart rate 72 time / min,with iDose^4 iteration reconstruction and prospective ECG-gated scanning in low concentration contrast medium and low radiation dose scanning the effect of contrast enhancement of blood vessels could still be improved without impairing the image quality,also the effective radiation dosage could be significantly lowered.

关 键 词：体层摄影术 X线计算机 前瞻性心电门控 辐射剂量 冠状动脉搭桥术 

分 类 号：R814.42[医药卫生—影像医学与核医学] R654.2[医药卫生—放射医学]