A Feasibility Study to Evaluate Replacing Conventional Computed Tomography at 120 KVP with Low Radiation Dose and Low Iodine Intake Based on Body Mass Index-Adapted Abdominal Computed Tomography Angiography in 291 Patients.

BACKGROUND This feasibility study aimed to evaluate replacing conventional computed tomography at 120 kVp with low radiation and low iodine dose based on body mass index (BMI)-adapted abdominal computed tomography angiography in 291 patients. MATERIAL AND METHODS A total of 291 abdominal CTA patients were divided into 3 individualized kVp groups according to their BMI: A1 with 70 kVp (n=57), A2 with 80 kVp (n=49), and A3 with 100 kVp (n=48); and 3 conventional 120 kVp groups: B1 (n=40), B2 (n=53), and B3 (n=44) BMI-matched with group A. The contrast media was 300 mgI/kg for group A and 500 mgI/kg for group B. The CT values and SD of the abdominal aorta and the erector spinae were measured, and the contrast-to-noise ratio (CNR) and figure-of-merit (FOM) were calculated. Imaging quality, radiation, and contrast media dosage were evaluated. RESULTS The CT and CNR of abdominal aorta in groups A1 and A2 were higher than those in groups B1 and B2 (P<0.05), but there was no significant difference between groups A3 and B3 (P>0.05). FOM of the abdominal aorta in group A was higher than that in group B (P<0.05). Compared with groups B1, B2, and B3, the radiation doses of A1, A2, and A3 groups decreased by 70.61%, 56.72%, and 31.87%, and contrast intake decreased by 39.94%, 38.74%, and 35.09%, respectively (P<0.05). CONCLUSIONS BMI-based individualized kVp abdominal CTA imaging significantly reduced overall radiation dose and contrast media intake while providing excellent image quality.