High-concentration contrast media combined with low tube current for radiation dose reduction in head and neck computed tomography angiography: A prospective study

High-concentration contrast media (HCCM) is a promising strategy to reduce radiation dose during computed tomography scan. This prospective study aims to assess whether the combination of HCCM and reduced tube current (mAs) can decrease radiation dose without compromising image quality in head and neck computed tomography angiography (CTA). A total of 68 consecutive patients (41 males, 27 females) with a mean age of 60.9 ± 10.9 years, referred for head and neck CTA, were randomly assigned to Group A (iodixanol 320, automatic mAs) and Group B (iomeprol 400, effective mAs reduced by a factor 0.64). CTA were performed with a tube voltage of 100 kV. Radiation dose was assessed by the volume CT dose index (CTDIvol), dose length product, and effective dose. Objective image quality was evaluated based on attenuation, signal-to-noise ratio, and contrast-to-noise ratio. Subjective image quality was rated using a 5-point Likert scale. Group B had significantly lower CTDIvol (4.22 ± 0.54 vs 6.48 ± 0.79 mGy) and dose length product (167.9 ± 24.5 vs 249.1 ± 35.7 mGy*cm) compared to Group A (P <.001). The effective dose in Group B was reduced by 32.5%. CT attenuation values for the internal carotid artery, middle cerebral artery, and aortic arch in Group B were significantly higher than those in Group A (P <.05). No significant differences were found in signal-to-noise ratio or contrast-to-noise ratio. The subjective quality for overall image and main head and neck arteries was significantly higher in Group B compared to Group A. In conclusion, the combination of HCCM and reduced mAs effectively reduces radiation dose without compromising image quality in head and neck CTA.