Clinical Application Of Low Concentration Contrast And Low Radiation Dose Scanning In Enhanced Pulmonary Nodule Examination

Objective: The feasibility of using isosmotic low concentration contrast agent(270mgI/ml),low tube voltage(100kVp)and iterative reconstruction technique for pulmonary nodule enhanced examination was investigated.Methods: The pulmonary nodules were removed from June 1,2017 to December 31,2017,and 92 patients were examined by CT enhanced scan in the 1 months prior to the operation.They were randomly divided into A,B,C,and D groups.Group A conventional dose scan group,120 kVp tube voltage,contrast agent concentration was 300mgI/ml;group B low tube voltage,tube voltage100 kVp,contrast agent concentration was 300mgI/ml;C group for the low concentration of contrast group,120 k Vp tube voltage,contrast agent concentration was 270mgI/ml;D group for double low group,tube voltage100 kVp,contrast agent concentration was 270mgI/ml.The iterative reconstruction algorithm uses sinogram afirmed iterative reconstruction(SAFIRE)technology.The CT value and SD of the main pulmonary artery,left pulmonary artery,right pulmonary artery,paravertebral muscle and pectoralis major muscle were measured in 4 groups.The noise of the four groups of images,the subjective image quality score and the effective radiation dose were compared.The diagnostic coincidence rate of the 4 groups was evaluated.Results: 1.Radiation dose: The effective radiation dose was reduced by about 19.7% between A and B,23.7% between C and D.2.Image quality: Comparison between the 4 groups,CNR were significantly different(P <0.05),the noise of 100 kV is higher than that of120kV;.there was no significant difference in subjective image quality score(P >0.05).3.Diagnostic coincidence rate: Between the 4 groups diagnostic coincidence rate was compared with each other,the difference was not statistically significant,and the P value was more than 0.05.Conclusion: Low tube voltage and low concentration contrast agent combined with sinusoidal iterative reconstruction algorithm can ensure the image quality while reducing the radiation dose and contrast agent concentration.The clinical application of CT in pulmonary nodules will not reduce the diagnostic accuracy.