Low volume of low concentration isotonic contrast medium for 320 row coronary CT angiography / 实用放射学杂志

ABSTRACT

Objective To investigate the feasibility of using low volume of low concentration isotonic contrast medium for 320 row coronary CT angiography.Methods 64 patients whose heart rate 70 beats per minute or less,normal cardiac rhythm,BMI≤24 kg/m2 were scanned using a 320 row dynamic volume CT with the tube voltage of 100 kVp and injection of contrast medium with a concentration 270 mg I/mL.Prospective ECG gating technique and adaptive iterative dose reduction algorithm reconstruction were used.In group A,22 patients were injected 50 mL contrast medium by a rate of 5.0 mL/s.In group B,21 patients were injected with the dosage of contrast medium calculated by 0.7 mL/kg and injection rate was 4.5 mL/s.In group C,21 patients were injected with the dosage of contrast medium calculated by 0.6 mL/kg and the injection rate was 4.0 mL/s.The attenuation value,signal-to-noise(SNR),con-trast-to-noise ratio(CNR),image quality and iodine intake between three groups were compared using One-Way ANOVA .Results There was no significantly statistical difference of age,sex ratio,BMI,heart rate between the three groups (P >0.05).However,the dosage of the contrast agent and different injection time had statistical significance (P 0.05).The image quality,SNR and CNR in three groups did not have significant difference (P >0.05).The total iodine and iodine injection rate were lowest in group C.Conclusion In 320 row coronary CT angiography with 100 kVp tube voltage and iterative reconstruction algorithm,the patients whose heart rate 70 beats per minute or less,BMI≤24 kg/m2 injected the low concentration of contrast medium by 0.6 mL/kg dose injection can give a good image quality which can meet the diagnostic requirement.Mean-while,it can also reduce the iodine intake and the risk of contrast induced nephrology (CIN).