Application of dual-source CT semi-automatic mode combined with ADMIRE in low-dose thoracic CT

Objective To explore the application of dual-source CT semi-automatic mode combined with advanced model iterative reconstruction (ADMIRE) in low-dose thoracic CT. Methods A total of 500 patients who were scheduled for chest CT were selected. The patients were randomly divided into five groups (n=100).Group F was a conventional dose group (with a tube voltage of 120 kV), and filtered back projection (FBP) was used for reconstruction. Groups A1, A1, B1 and B2 were low dose groups (with a tube voltage of 80 kV for groups A1 and A2 and a tube voltage of 70 kV for groups Bl and B2). Groups A1 and B1 turned on semi-automatic mode (semi), and ADMIRE (grade 3) was used for reconstruction. Groups A2 and B2 turned off semi-automatic mode, while other conditions were the same as those in groups A1 and B1. The conventional group and each low dose group were evaluated for image quality according to subjective and objective indexes. Results The signal/noise ratios (SNRs) of groups A1, B1 and F were better than those of groups A2 and B2. There were significant differences in CT dose index (CTDI), dose length product (DLP) and effective dose (ED) between group F and the low dose groups (P<0.05). There was no difference in subjective evaluation of image quality in groups F, A1, A2 and B1, but the worst was found in group B2 (P<0.05). The artifact scores of harness sclerosis in groups B1 and B2 were lower than those in groups F, A1 and A2 (P<0.05). Conclusions In low-dose chest CT scanning, semi-automatic mode combined with ADMIRE algorithm can reduce the radiation dose while ensuring image quality.