Application of 70 kV tube voltage combined with low dose and low concentration of contrast medium in CCTA
10.3969/j.issn.1002-1671.2018.03.028
- VernacularTitle:70kV管电压联合低剂量及低浓度对比剂在CCTA中的应用研究
- Author:
Yanhong ZHAO
1
;
Xiaowen ZHANG
;
Wanqing HAO
;
Dazhi CHEN
;
Yongpei CAO
;
Jia WAN
;
Ruoshui HA
Author Information
1. 北方民族大学(宁夏人民医院教学合作医院)
- Keywords:
computed tomography;
image quality;
radiation dose;
contrast medium
- From:
Journal of Practical Radiology
2018;34(3):431-434
- CountryChina
- Language:Chinese
-
Abstract:
Objective To access the effects of 70 kV tube voltage combined with low dose and low concentration of contrast medium in coronary CT angiography (CCTA)by evaluating the image quality,radiation dose and contrast medium dosage.Methods Ninety patients suspected with coronary artery disease with body mass index(BMI)of less than 25 kg/m2and heart rate (HR)of less than 75 beats per minute were enrolled.The patients were randomly divided into three groups (n=30 for each group):Group A,100 kV of tube voltage with 370 mg I/mL iopromide,1 mL/kg;Group B,80 kV with 270 mg I/mL iodixanol,1 mL/kg;Group C,70 kV with 270 mg I/mL iodixanol,0.8 mL/kg.All the patients underwent CCTA with a 256 row wide-coverage volumetric CT.Automatic tube current modulation technique was applied.The images were reconstructed by adaptive statistical iterative reconstruction V (ASIR-V).The subjective image quality scores were compared with rank-sum test.The signal-to-noise ratio (SNR),contrast-to-noise ratio(CNR),effective dose(ED)and the total iodine intake were calculated and compared with one-way ANOVA.Results No statistically differences in age,gender,heart rate and BMI were observed among the three groups (P>0.05).Subjective image quality scores had no difference among the three groups (P>0.05).The CT values of group C were higher than those of group A(P<0.05).The image noise of group C was higher than that of group A and group B (P<0.05).No significant differences in SNR and CNR were noticed among the three groups (P>0.05).The ED of group B (0.39±0.08)mSv and group C (0.19±0.01)mSv were lower than that of group A (0.81±0.19)mSv (each P<0.05).Compared with group A,the decrease rates of ED of group B and C were 51.8% and 76.5% respectively.Compared with group A and group B,the total iodine intake of group C was decreased by 25% and 21.4% (P<0.05).Conclusion 70 kV of tube voltage combined with low dose and low concentration of contrast medium in CCTA can reduce the radiation dose and iodine intake without compromising image quality.
