The application of low dose contrast agent in the head and neck CTA with the peak concentration and duration of the target blood vessel contrast agent

LAI Yulin; GUO Jianxiong; WEN Xiaoqin; LI Songfu; YUAN Zupeng

Abstract：Objective To study the feasibility of the scheme of lowering usage of contrast agents in head and neck CTA. Methods Through the different concentration of contrast medium corresponding CT value, we estimated the required concentra-tion of target intravascular contrast medium. According to the results from the previous researches, we determined the correspond-ing concentration of contrast agent that was the best for head and neck CTA. On the basis of cardiac output, CT scanning time, and the total blood volume to the target vascular circulation, we calculated the concentration of contrast medium. 68 patients, who underwent head and neck CTA in our hospital, were randomly divided into two groups:the low contrast group given low dose con-trast and the control group given regular doses for CTA scanning. 360 HU of CT value measured at the carotid bifurcation was con-sidered to be qualified and 460 HU, to be the best. And then, the comparison was statistically conducted respectively. Results As for the head and neck CTA, the contrast agent dose in low dose group was reduced by about 50%. The eligibility or good rate of CT value for target vascula had no statistical difference compared with that in the control group. Conclusion In the head and neck CTA inspection, the usage of low contrast agent dose according to contrast medium concentration from the individual target blood vessels and duration of peak value can ensure the quality of imaging of the individualized scanning solution, making the use of contrast medium is appropriate.