Application of CARE kV and SAFIRE in Contrast-Enhanced Chest CT Examination

Objective To evaluate the feasibility of automated tube potential selection algorithm(CARE kV) and Sinogram Affirmed Iterative Reconstruction(SAFIRE) on chest CT image quality improvement and radiation dose reduction.Methods Sixty consecutive patients with neoplasms were enrolled and divided into 2 groups equally.Patients of group 1 underwent 128 slice DSCT routine scan,and the images were reconstructed with FBP.The patients of group 2 underwent 128 slice DSCT CARE kV scan,and the images were reconstructed with FBP(group 2a) and SAFIRE(group 2b) separately.The image quality was evaluated by two observers using 5-point score(5: excellent to 1: non-diagnostic) independently.Image attenuation and noise were measured,contrast-to-noise-ratio(CNR) was calculated,the basic information of patients,such as age and gender,as well as radiation dose were recorded.Results The average image quality score of groups 1,2a and 2b was 3.83,3.60,4.33 respectively.The image quality of group 2b and 2a was better than that of group 1(K= 0.749,P=0.003).The CNR of group 2a and 2b was increased to 16.7%(t=2.065,P=0.043),61.2%(t=6.312,P0.001)compared with that of group 1.The effective radiation dose of group 2(2.26±0.77) mSv was significantly lower than that of group 1(2.82±1.15),corresponding to an overall dose reduction of 19.7%(t=3.370,P=0.001).Conclusion Combined application of both CARE kV and SAFIRE can improve image quality and reduce the radiation dose of patients.