Comparison of effectiveness of 400 mgI/ml and 370 mgI/ml nonionic contrast medium on spinal CTA

Objective:To test the hypothesis that the 400 mgI/ml nonionic contrast medium can promote CTA image quality of the anterior spinal artery(ASA) and artery of Adamkiewicz(AA),compared with 370 mgI/ml nonionic contrast medium.Methods:103 patients who underwent spinal CTA scan were divided into two groups: 370 mgI/ml group(n=51) and 400 mgI/ml group(n=52).Raw image data was reconstructed by adapted brain algorithms and small DFOV.It was studied:(1) CT value in originated part of the descendent aorta;(2) the visualization of ASA and AA in CTA;(3) contrast-to-noise ratios(CNR) at four deferent levels along the course of AA;(4) the image quality scores of ASA and AA.Results:CT value in originated part of the descendent aorta was(305.5±23.7) HU in 370 mgI/ml group and(367.4±19.8) HU in 400 mgI/ml group,there was a statistic difference between them(t=2.23,P0.05).The ASA and AA can be 100% visualized in all patients of both groups.The CNR of the feeding artery of AA(intercostal artery or lumber artery) was 24.11±4.43 and 27.88±5.12 in 370 mgI/ml group and 400 mgI/ml group,respectively.There was a statistic difference between them(t=3.998,P0.05).The CNR at the level of AA in vertebrae foramen,vertebrae canal and the cranial part of the ASA were 7.23±4.28,6.08±1.17 and 9.72±1.91 in 370 mgI/ml group,as well as 7.87±4.72,6.53±1.52 and 9.49±2.01 in 400 mgI/ml group.However,all of CNR at the levels of the AA in vertebrae foramen(t=0.316),in vertebrae canal(t=0.894) and the cranial part of the ASA(t=0.564) did not show significant difference between the two groups(P0.05).Furthermore,the image quality scores of ASA and AA indicated there were also no differences between them(χ2=0.317,P0.05;χ2=0.569,P0.05).Conclusion:Compared with 370 mgI/ml nonionic contrast medium,400 mgI/ml contrast medium can provide higher attenuation of blood vessels due to its higher iodine concentrations,but it can not promote the image quality of ASA and AA in multi-detector CT(MDCT) spinal CTA examination.