双低扫描技术结合双源CT Flash Spiral模式在冠状动脉成像中的应用  

Application of Double Low Scanning Combined with Flash Spiral Model of Dual-Source CT in Coronary Angiography

作　　者：周俊[1] 魏蓉[1] 

机构地区：[1]兰州石油化工公司总医院放射科,730060

出　　处：《临床放射学杂志》2016年第9期1437-1440,共4页Journal of Clinical Radiology

摘　　要：目的探讨双源CT Flash Spiral扫描模式下,270碘对比剂结合低管电压及正弦确认迭代重组(SAFIRE)技术在改善冠状动脉成像图像质量及降低辐射剂量中的价值。方法将平均心率<65次/分的82例疑诊冠心病患者随机分为A、B两组,A组42例,采用管电压120 k V、350 mg I/m L的对比剂,重组图像采用滤过反投影(FBP)法;B组40例,采用管电压80 k V或100 k V、270 mg I/m L的对比剂,重组图像同时采用FBP法(B1组)和SAFIRE法(B2组)。A、B两组均采用Flash Spiral模式扫描,采集图像时间为R-R间期60%。记录剂量长度乘积(DLP),计算有效辐射剂量(ED)。测量A组与B组两种重组法主动脉根部、左冠状动脉及右冠状动脉起始部血管内CT值和图像噪声(SD),计算主观图像质量评分、图像噪声(SD)、信噪比(SNR)、对比噪声比(CNR)。结果 A、B两组的ED分别为(1.18±0.21)m Sv、(0.55±0.19)m Sv,差异有统计学意义(t=14.22,P<0.01);A组与B组两种重组法B1、B2冠状动脉图像质量评分分别为1.57±0.60、1.85±0.59、1.55±0.60,SD分别为(17.62±2.44)HU、(27.25±8.06)HU、(19.21±6.21)HU,B1与B2组间均有显著统计学差异(P<0.01),A与B2组间均无统计学差异(P>0.05);血管内强化CT值、SNR、CNR B2组均高于A组,有统计学差异(P<0.05)。结论双源CT Flash Spiral扫描模式下,270碘对比剂结合低管电压及SAFIRE技术能明显降低辐射剂量,并能获得较好的图像质量。Objective To investigate the value of 270 iodinated concentration of contrast agent combined with the low tube voltage and sinogram-affirmed iterative reconstruction（ SAFIRE） improving image quality and reducing radiation dose in dual source CT Flash spiral scan mode of coronary angiography. Methods 82 patients with coronary artery disease and mean HR 65 beats per minute（ bpm） were randomly divided into A,B groups. Group A（ 42 patients） were scanned in120 k V with 350 mg I / ml iodinated contrast agent mode,and images were reconstructed using filtered back projection（ FBP）. Group B（ 40 patients） were scanned in 80 or 100 k V with 270 mg I/ml iodinated contrast agent mode,and images were reconstructed using filtered back projection（ FBP） in group B1 and iterative reconstruction technique（ SATIRE,Siemens Healthcare） in group B2. All 82 patients were scanned in prospectively ECG-triggered spiral acquisition mode（ Flash Spiral mode）,and the time of image capture was 60% of R-R interphase. We took notes of the dose length product（ DLP）and calculated effective radiation dose（ ED）. CT attenuation and image noise were measured between two groups in the aortic root,left coronary artery and the beginning of right coronary artery. Subject image quality scores,image noise,signalto-noise ratio（ SNR）,contrast-to-noise ratio（ CNR） were recorded. Results The effective radiation doses（ ED） were（ 1. 18 ± 0. 21） m Sv、（ 0. 55 ± 0. 19） m Sv in group A and B,they have significant differences（ t = 14. 22,P〈0. 01）; The image quality average scores between group A、B1、B2 were 1. 57 ± 0. 60、1. 85 ± 0. 59、1. 55 ± 0. 60; The average image noise values were（ 17. 62 ± 2. 44） HU、（ 27. 25 ± 8. 06） HU、（ 19. 21 ± 6. 21） HU respectively. There were highly significant differences between group B1 and B2（ P〈0. 01）. For group A and B2,there were no significant differences（ P〈0. 05）.Intravascular enhancement CT attenuation,SNR,and CNR showed

关 键 词：对比剂 低浓度 体层摄影术 X线计算机 冠状动脉 大螺距 迭代重组 

分 类 号：R816.2[医药卫生—放射医学] R541.4[医药卫生—临床医学]