Feasibility of Double Low Dose Technology in Multi-slice Head and Neck CT Angiography Without Adaptive Statistical Iterative Reconstruction / 中国医学影像学杂志

ABSTRACT

Purpose To explore the feasibility of double low dose technology in multi-slice head and neck CT angiography, so to reduce contrast agent as well as reduce radiation dose. In that way, the hazards of radiation and the risk of contrast induced nephropathy would be reduced. Materials and Methods Fifty-one patients took double low proposal were recruited as double low group. Another 51 patients who took conventional proposal were recruited as conventional group. The scanning parameters of double low group were 100 kV, 300 mA, 0.7 ml/kg iodinated contrast agent and which of conventional group were 120 kV, 350 mA, 1.0 ml/kg iodinated contrast agent. The CT value of the vessels and image noise were measured. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective image quality score, radiation dose and iodine load between the two groups were compared. Results The volume CT dose index (CTDIvol) of the double low group and the conventional group were 18.00 mGy and 33.86 mGy, respectively. And the effective dose were 3.85 mSv/(mGy · cm) and 7.25 mSv/(mGy · cm), respectively. The iodine loads were 224 mgI/kg and 320 mgI/kg, respectively. SNR and CNR at the aortic arch were higher in double low group than in conventional group, but which was not statistic significant (t=-1.572 and -1.783, P>0.05). The SNR and CNR of bilateral carotid arteries, internal carotid arteries, and middle cerebral arteries had no statistic significance between the two groups (t=0.341-1.739, P>0.05). The subjective image quality scores of double low group and conventional group were (3.69±0.47) scores and (3.70±0.46) scores, which showed no statistic difference (Z= - 0.213, P>0.05). Conclusion Approving images of multi-slice head and neck CT angiography can be obtained by using double low dose technology without adaptive statistical iterative reconstruction.