回顾性心电门控下双低剂量支气管动脉CTA的应用研究

Applicative Study of Double Low Dose Combined with Retrospective ECG Gating in Bronchial Artery CT Angiography

目的:探讨回顾性心电门控下低管电压低浓度对比剂支气管动脉(BA)CTA的应用价值。方法:将120例咯血患者随机分为常规剂量组(A组)及双低剂量组(B组)各60例,采用64排CT行BA-CTA。两组均行增强动脉期扫描,A组管电压120 kV,对比剂浓度350 mgI/mL,B组管电压80 kV,对比剂浓度270 mgI/mL,运用回顾性心电门控采集图像。扫描结束后重建图像,并分析两组BA的显示率、图像质量、辐射剂量及碘摄入量的差异。结果:两组成功完成检查115例(A组57例,B组58例)。B组BA的显示率高于A组(P<0.05);B组图像优良率及合格率、噪声、BA的CT值、SNR、CNR均高于A组(P<0.05);B组CTDIvol、DLP、ED、碘摄入量均低于A组(P<0.05)。结论:回顾性心电门控下低管电压低浓度对比剂BA-CTA具有重要临床价值,既能提高图像质量,又能显著降低辐射剂量,并减少碘摄入量。

Objective:To explore the applicative value of low tube voltage and low concentration contrast agent bronchial artery(BA)CTA under retrospective ECG gating.Methods:120 patients with hemoptysis were randomly divided into conventional dose group(group A)and double low dose group(group B),60 cases in each group.Both groups underwent enhanced arterial phase scanning.The tube voltage was 120 kV and the concentration of contrast medium was 350 mgI/mL in group A,while the tube voltage was 80 k V and the concentration of contrast medium was 270 mgI/mL in group B.The CTA images were reconstructed after scanning,and the differences of BA display rate,image quality,and radiation dose and iodine intake between the 2 groups were analyzed respectively.Results:115 cases completed scan successfully in the 2 groups(57 cases in group A and 58 cases in group B).The display rate of BA in group B was higher than that of group A(P<0.05);The excellent rate and qualified rate of image,noise,CT value,SNR and CNR of BA in group B were higher than those of group A(P<0.05);CTDIvol,DLP,ED and iodine intake in group B were lower than those of group A(P<0.05).Conclusion:Low tube voltage and low concentration contrast agent combined with retrospective ECG gating show important value in BA-CTA,image quality can be improved,the radiation dose and iodine intake can be reduced obviously.