宽体探测器CT冠状动脉成像优化对比剂注射时间与不同管电压相关性研究  

Correlation between contrast injection time and tube voltages for coronary imaging optimization with wide-detector CT

作　　者：赵芳芳 李安 ZHAO Fangfang;LI An(Shaanxi Provincial People’s Hospital,Xi’an 710068,China)

机构地区：[1]陕西省人民医院,陕西西安710068 [2]长安医院医学影像科,陕西西安710016

出　　处：《陕西医学杂志》2023年第5期563-566,共4页Shaanxi Medical Journal

摘　　要：目的:探讨Revoluntion宽体探测器CT冠状动脉成像优化对比剂注射时间与不同管电压的相关性。方法:收集拟诊冠心病并行Revolution CT冠状动脉成像(CCTA)受检者60例作为研究对象,随机分为两组。A组为对照组(30例),管电压为120 kV;B组为试验组(30例),管电压为100 kV。对比剂注入时间均为8 s,按照25 mgI/(kg·s)碘流率计算打药药量,迭代重组(ASIR-V)权重80%,联合冠脉冻结技术(SSF)重建图像。分别测量主动脉根部、右冠状动脉(RCA)、左前降支(LAD),以及左回旋支(LCX)近段管腔和其周围脂肪组织CT值,计算血管信噪比(SNR)和对比噪声比(CNR)。记录CT容积剂量指数(CTDI)、长度乘积(DLP),并计算有效辐射剂量(ED);由两名具有心血管影像高年资医师根据美国心脏协会(AHA)冠状动脉改良分段法(分16段)及远端分支运用5分法进行图像质量主观评价,应用Kappa检验判断观察者间一致性。比较两组间一般资料,图像质量主、客观评价指标及ED。结果:两组患者一般资料、造影剂用量、主观评分等比较差异均无统计学意义(均P>0.05);CTDI、DLP、ED比较差异均有统计学意义(均P<0.05);B组ED较A组下降约30%。两组间各节段血管内CT值比较B组较A组提升,差异有统计学意义(均P<0.05);两组间SNR、CNR比较差异无统计学意义(均P>0.05)。结论:宽体探测器CT冠状动脉成像优化对比剂注射时间8 s,在低管电压100 kV图像质量优于高管电压120 kV,且可以有效降低辐射剂量。Objective:To study the correlation between contrast injection time and tube voltages for coronary imaging optimization with wide-detectors.Methods:A totalt of 60 patients with suspected coronary heart disease who underwent CT coronary angiography(CCTA)were collected and divided into two groups.Group A(30 cases)was control group,and the tube voltage was 120 kV.Group B(30 cases)was the study group,and the tube voltage was 100 kV.Contrast agent injection time was 8 seconds.The contrast dosage was calculated according to the iodine flow rate of 25 mgI/(kg·s),and the 80%ASIR-V images were reconstructed with SSF.CT values of proximal aortic root,right coronary artery(RCA),left anterior descending artery(LAD),and left circumflex artery(LCX)lumens and their surrounding adipose tissue were measured to calculate vascular SNR and CNR.CTDI and DLP were recorded to calculate the effective dose(ED).Subjective imaging qualities were compared and interobserver agreement was evaluated with kappa values.The general data,subjective and objective evaluation indexes of image quality and ED were compared between the two groups.Results:There were no significant differences in patient demographics,contrast agent consumption and subjective scores between these two groups(P>0.05).There were significant differences in CTDI,DLP and ED(all P<0.05).ED of Group B decreased by 30%compared with group A.The intravascular CT values were increased in group B compared with group A(all P<0.05).There were no significant differences in SNR and CNR between the two groups(all P>0.05).Conclusion:The image quality at low tube voltage 100 kV with optimized contrast agent injection time of 8 s is superior to the high tube voltage 120 kV,and can reduce radiation dose effectively.

关 键 词：Revolution CT 冠状动脉成像 管电压 对比剂 辐射剂量 图像质量 

分 类 号：R445.4[医药卫生—影像医学与核医学]