Application of Low-dose Contrast Agent in 256-slice CT Angiography for Head-and-neck / 中国医学影像学杂志

ABSTRACT

Purpose To investigate the feasibility of 30 ml low-dose contrast medium in reducing the accumulation of contrast medium in venous system while maintaining enough artery enhancement in 256-slice CT angiography (CTA) of intracranial and cervical arteries.Materials and Methods Sixty patients with head and neck CTA were recruited prospectively,and they were randomly divided into group A and group B.The scan parameters of the two groups were identical,but the protocol of contrast medium injection was different.Group A was injected 60 ml contrast medium and 30 ml saline successively with the rate of 4.0 ml/s.Group B was injected 30 ml contrast medium and 50 ml saline successively with the rate of 5.0 ml/s.CT attenuation values of aortic arch,common carotid artery,subclavian artery,cerebral middle artery,superior vena cava,innominate vein,subclavian vein,internal jugular vein were measured,and the image quality was evaluated.Results The average CT values of superior vena cava,right innominate vein,right subclavian vein in two groups had significant differences (P＜0.05).The average CT values of left brachial vein,left subclavian vein,left and right internal jugular vein in two groups had no significant differences (P＞0.05).The average CT values of aortic arch,left and right common carotid artery,left and right subclavian artery,left and right cerebral middle artery in two groups had significant differences (P＜0.05).The scores of image quality in two groups also had significant difference (P＜0.05).Conclusion Head-and-neck CTA with 30 ml low-dose contrast medium is feasible and the images are satisfactory for diagnosis,which can reduce the dose of contrast medium and accumulation of contrast medium in venous system,while maintaining enough artery enhancement.