The preliminary study of using low concentration of isotonic contrast agent on bronchial artery CTA / 实用放射学杂志

ABSTRACT

Objective To evaluate the value of low concentration of isotonic contrast agent combined with 80 kV and adaptive statistical itera-tive reconstruction (ASiR)technique for bronchial artery with CT angiography (CTA).Methods 40 patients (18.5 kg/m2 ≤ body mass index(BMI)≤25 kg/m2 )with lung cancer were randomly divided into two groups and performed enhanced chest CT examina-tion.20 patients (low concentration group)were scanned with Visipaque 270mg I/mL,scanning protocol of (80 kV,260 mA)and other 20 patients (high concentration group)were scanned with Ultravist 370 mg I/mL,scanning protocol of (120 kV,1 50 mA). The CT value,signal noise (SD),signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR)and effective dose (ED)of the two groups were compared and analyzed statistically.Differences between the two groups were determined with t test(P <0.05).Results The mean CT value of the low concentration group (31 7.33 HU±70.44 HU)was higher than that of the high concentration group (256.39 HU±37.38 HU)(P <0.05).SD,ED and dose length product (DLP)of the low concentration group (SD7.55 ±1.51 HU;ED1.74±0.14 mSv;DLP124.94±9.9 mGy/cm)were lower than those of the high concentration group (SD9.36±1.26 HU;ED3.20±0.35 mSv;DLP228.82±25.13 mGy/cm)(P <0.05).CNR and SNR of the low concentration group (CNR59.71± 17.36;SNR44.01±14.71)were higher than those of the high concentration group (CNR37.61±6.16;SNR27.75±4.72)(P <0.05).The subjective scores of the two groups were (3.73±0.66)and (3.81±0.59),respectively,with no statistical difference.Conclusion For the patients with normal body mass index ,it can reduce 47% radiation dose and 27% iodine dosage using low concentration of isotonic contrast agent combined with 80kV and ASiR technique for bronchial artery CTA,while maintaining similar excellent image quality.