目的:探讨64排CT进行大范围动脉血管检查应用低电压、小剂量对比剂时的可行性,并评价图像质量。方法:前瞻性将72例行主动脉血管CT血管造影(CTA)检查患者随机分为A组20例、B组32例和C组20例。各组扫描参数、对比剂用量分别为A组:120 kV、260 mA、80 mL;B组为 120 kV、260 mA、50 mL;C组为80 kV、260 mA、50 mL。比较并统计各组间肝门水平位置的主动脉部强化程度从而评估图像质量以及有效吸收剂量的差异。结果:主动脉CT值超过200 HU的峰值持续时间为(10±4)s。动脉平均增强CT值,A组大于B组,B组大于C组,但没有统计学差异,图像质量A、B、C 3组均能满足诊断要求。患者有效吸收剂量C组明显低于A、B两组(P<0.01)。结论:应用64排CT进行主动脉血管检查,使用小剂量对比剂及低管电压可行,图像质量满足诊断需要,患者的吸收剂量下降。
[1]Bae K T, Heiken J P, Brink J A. Aortic and hepatic contrast medium enhancement at CT. Part Ⅱ. Effect of reduced cardiac output in a porcine mode[J]. Radiology,1998,207(3):657
[2]Hittmair K, Fleischmann D. Accuracy of predicting and controlling time-dependent aortic enhancement from a test bolus injection[J]. J Comput Assist Tomogr, 2001,25(2):287
[3]Szucs-Farkas Z, Schibler F, Cullmann J, et al. Diagnostic accuracy of pulmonary CT angiography at low tube voltage: intraindividual comparison of a normal-dose protocol at 120 kVp and a low-dose protocol at 80 kVp using reduced amount of contrast medium in a simulation study[J]. AJR Am J Roentgenol, 2011,197(5):W852
[4]Szucs-Farkas Z, Schaller C, Bensler S, et al. Detection of pulmonary emboli with CT angiography at reduced radiation exposure and contrast material volume: comparison of 80 kVp and 120 kVp protocols in a matched cohort[J]. Invest Radiol, 2009,44(12):793
[5]Huda W, Ogden K M, Khorasani M R. Converting dose-length product to effective dose at CT[J]. Radiology, 2008,248(3):995
[6]Sahani D V, Kalva S P, Hahn P F, et al. 16-MDCT angiography in living kidney donors at various tube potentials: impact on image quality and radiation dose[J]. AJR Am J Roentgenol, 2007,188(1):115
[7]Kalva S P, Sahani D V, Hahn P F, et al. Using the K-edge to improve contrast conspicuity and to lower radiation dose with a 16-MDCT: a phantom and human study[J]. J Comput Assist Tomogr, 2006,30(3):391
[8]Szucs-Farkas Z, Kurmann L, Strautz T, et al. Patient exposure and image quality of low-dose pulmonary computed tomography angiography: comparison of 100- and 80-kVp protocols[J]. Invest Radiol, 2008,43(12):871
作者简介 王欣宇(1986-),男,技师,学士,研究方向:医学影像学;通信作者:李锋坦,E-mail :left9999@sina.com。