低管电压、低浓度对比剂冠状动脉CTA检查的可行性分析  

The feasibility analysis of coronary computed tomography angiography with low tube voltage and low iodine concentration contrast

作　　者：贾艳荣[1] 张浩亮[1] 徐彦东[1] 刘智君[1] 奇丽霞 杜海[1] 刘慧[1] 耿明明[1] 

机构地区：[1]内蒙古自治区鄂尔多斯市中心医院CT室,内蒙古鄂尔多斯017000

出　　处：《医学影像学杂志》2016年第9期1573-1577,1581,共6页Journal of Medical Imaging

摘　　要：目的探讨宝石能谱CT采用低管电压、低浓度对比剂行冠脉CTA检查的可行性分析。方法搜集我院行冠脉CTA检查、BMI<28kg/m2的患者170例,随机分为A、B两组,A组85例为双低组,管电压100k V,管电流500m As,对比剂威视派克270mg I/ml,ASiR40%迭代重建;B组85例为常规组,管电压120k V,管电流500m As,对比剂欧乃派克350mg I/ml,FBP重建。两组均采用前置性门控成像序列,扫描后将图像传入工作站进行后处理。图像质量由两名高年资放射科医生进行双盲法主观评分。客观评价为测量主动脉根部(AO)、左主干(LM)、左前降支(LAD)、左回旋支(LCX)及右冠状动脉(RCA)近端的CT值及噪声,计算信号噪声比(SNR)及对比噪声比(CNR),记录辐射剂量(CTDIvol,DLP,ED)、碘摄入量进行统计学分析。采用2个独立样本的t检验和非参数检验,P<0.05认为差异有统计学意义。结果在辐射剂量上,双低组的CTDIvol、DLP、ED及碘摄入量明显低于常规组(P<0.05),而图像质量评分无统计学差异,双低组在主观评分上略优于常规组。客观评价中,双低组中一半指标(10个)的图像质量有显著提高(P<0.05),特别是CT值,在5个部位的比较中均有显著提高。另外,双低组中,多个部位的相关性分析提示CNR、SNR与BMI呈显著负相关(P<0.05),而在常规组中,尚不能认为有相关性存在。结论采用低管电压100k Vp,低浓度对比剂威视派克270mg I/ml联合ASiR40%行冠脉CTA检查不仅可以获得良好的图像,而且大幅度降低了辐射剂量和碘摄入量。Objective To investigate the feasibility of using low tube voltage and low iodine concentration contrast （Dual Low） CT scan techniques in Coronary CTA （CCTA）. Methods 170 patients undergoing CCTA with BMI 〈 28 kg/m2 were di- vided into two groups randomly. Group A （85 patients） was the dual-low group, which was scanned with tube voltage of 100 kVp, tube current of 500 mAs and injected with iso-osmolarity contrast agent Visipaque 270（270 mgI/ml） with ASiR 40% reconstruc- tion. Group B （85 patients） was the control group, which was scanned with tube voltage of 120 kVp, tubecurrent of 500 mAs and injected with low-osmolarity contrast agent Omnipaque 350（350 mgI/ml） with FBP reconstruction. Both groups were scanned with perspective cardiac gating, after scanning the images transmited to the workstation for rcproeessing. The images were assessed sub- jectively by two experienced radiologists with double-blindly. Objective assess was five ROIs that were placed onto the ascending root of Aorta （AO）, Left Main Artery （LM） , Left Anterior Descending （LAD） , Left Circumflex Artery （LCX）, Right Coronary Artery （RCA）, and the image qualities were evaluated objectively using CT values, noise, Signal Noise Ratio （SNR）, Contrast Noise Ratio （CNR）. The radiation dosages （ CTDIvol, DLP and ED） and iodine intake were also recorded and compared. Staffs- tics were used two independent samples paired t-test and nonparametric test, P 〈 0.05 considered the difference was statistically significant. Results On radiation dose, CTDIvol, DLP, ED and iodine intake of group A （ Dual Low） were obviously lower than Group B （ P 〈 0.05 ）. The image qualities of the two groups were not significantly different, the subjective assess of group A was superior to the group B. On Objective assess, the half of indexs （10） of the image quality was improved significantly （ P 〈 0. 05）, especially the CT value, in five parts, were all have improved significantly. In addition, in

关 键 词：体层摄影术 X线计算机 辐射剂量 图像质量 

分 类 号：R814.42[医药卫生—影像医学与核医学] R543.7[医药卫生—放射医学]