Abstract：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 A1(n=25) and A2(n=35) according to body mass index(BMI). Group A1(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(χ2=1.10 and 2.04, P>0.05). The SD, SNR and CNR of images also showed no statistical 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.
2014, Vol. 25 
