低浓度对比剂在冠状动脉CTA检查中的可行性研究

Feasibility of low concentration contrast medium in coronary CT angiography

目的:探讨低浓度碘对比剂(270 mgI/mL)配合低管电压在冠状动脉CTA检查中的可行性。材料与方法:将90例行冠状动脉CTA检查的患者随机分为A组和B组。A组60例应用270 mgI/mL碘对比剂同时使用迭代算法重建,再将A组根据体质量指数(BMI)分为A1组(25例)及A2组(35例),A1组(BMI<24 kg/m2)管电压为80 kV,A2组(BMI≥24 kg/m2)管电压为100 kV;B组30例应用370 mgI/mL碘对比剂,120 kV管电压。两组均采用前瞻性心电门控扫描。记录扫描辐射剂量,并对图像质量进行主、客观分析。结果:平均有效辐射剂量(ED)A1组为(2.00±0.56)mSv,A2组为(2.35±0.74)mSv,B组为(3.98±1.78)mSv,A1组与B组间及A2组与B组间均有统计学差异(t值分别为-5.34和-4.95,P<0.05)。图像质量方面,A1组与B组间及A2组与B组间主观评价优秀率无统计学差异(χ2值分别为1.10和2.04,P值均>0.05);客观评价图像噪声(SD)、信噪比(SNR)、对比噪声比(CNR)亦均无统计学差异。结论:应用尽可能低浓度的碘对比剂(270 mgI/mL)配合低管电压在冠状动脉CTA检查中是可行的,超重人群(BMI≥24 kg/m2)亦可应用,同时显著的降低了辐射剂量和碘注射量。

Objective： To explore the feasibility of using low concentration contrast medium（270 mgI/mL） with the low tube voltage in coronary artery CTA. Materials and Methods： Ninty patients with coronary CTA examination were divided into group A and group B randomly. Group A （n=60） used contrast medium of 270 mgI/mL with sinogram-affirmed iterative reconstruction（SAFIRE）. Group A was further divided into group Al（n=25） and A2（n=35） according to body mass index（BMI）. Group Al（BMI〈24 kg/m2） 80 kV was used for scanning, group A2（BMI≥24 kg/m2） 100 kV. The concentration of contrast medium and the tube voltage of group B （n=30） were 370 mgI/mL and 120 kV. All groups were scanned in prospective ECG-trigger gated. Radiation dose was recorded and image quality was analysed subjectively and objectively. Results： The effective dose （ED） of group A1, A2 and B were （2.00±0.56）mSv, （2.35±0.74）mSv and （3.98±1.78）mSv respectively, between group A1 and B, group A2 and B there were statistically significant（t=-5.34 and -4.95, P〈0.05）. In image quality, there were no statistical differences between each groups in the excellent rate （x2=l.10 and 2.04, P〉0.05）. The SD, SNR and CNR of images also showed no sta- tistical differences by objectively evaluated. Conclusion： Using low concentration contrast medium （270 mgI/mL） with low tube voltage in coronary artery CTA is feasible, especially in overweight（BMI≥24 kg/m2） population. At the same time, the radiation dose and concentration of iodine injection are reduced significantly.