Abstract：Objective To explore the application of 80kV combined with low-dose contrast medium and iterative reconstruction
in enhanced chest CT. Methods A total of 120 patients with bady mass index (BMI)<24 kg/m2 underwent chest CT enhanced
examination, and were divided into A, B and C groups by random number table method, with 40 patients in each group. The tube voltage
of A group was 120 kV, and the dose of contrast medium was 1.5 mL /kg, the tube voltage of B group was 100 kV, and the dose
of contrast medium was 1.2 mL /kg, the tube voltage of C group was 80 kV, and the dose of contrast medium was 1.0 mL/kg丨 FBP
reconstruction was used in A group, and 50%ASIR reconstruction was used in B group and C group. Analysis of variance was used
to compare subjective image quality score, objective image quality evaluation, radiation dose and iodine intake of the three groups.
Results The subjective score of image quality of the three groups was consistent, and the difference was not statistically significant，
P>0.05. The differences in CT value, image noise, SNR and CNR of thoracic aorta in A group, B group and C group were statistically
significant, P<0.05. the differences of radiation dose and iodine intake in A group, B group and C group were statistically significant,
P<0.05. Conclusion For enhanced chest CT examination of patients with BMI<24 kg/m2, 80 kV low tube voltage combined with
1.0 mL/kg low dose contrast medium and 50% ASIR can obtain excellent image quality and achieve ideal application effect of
reducing radiation dose and iodine intake.
