Comparative Study On CT Angiography Of Rabbits With Different Iodine Concentration Of Contrast Media

Objective: To compare the effect of intra-individual contrast enhancementon the computed tomography angiography (CTA) of rabbits with contrastmedias of different iodine concentration.Methods：Fifteen rabbits underwent repeat abdominal CTA by using twodifferent concentration of contrast media (Group A with Iodixanol270mgI/ml,Group B with Iopromide300mgI/ml). Then digital subtraction angiographywould be carried out after CTA, and each examination was performed with theminimum time interval of24hours. The density values of abdominal aorta andimage quality were compared.Results: The attenuation values in the aorta abdominalis at the level ofanterior mesenteric artery were（482±69）Hu and（517±92）Hu for Group Aand Group B, respectively(P=0.002); The attenuation values in the aortaabdominalis at the level of Right renal artery were（449±70）Hu and（483±90）Hu for Group A and Group B, respectively(P=0.002)；The attenuation valuesin the aorta abdominalis at the level of arteria iliaca communis were （410±84）Hu and444±67）Hu for Group A and Group B, respectively(P=0.001). Theoverall vascular density of the abdominal aorta down to the segmental level wassignificantly higher with Group B than Group A (all P＜0.05). In a subjectiveassessment,9showed excellent and6showed good in Group A，whereas11 showed excellent and4showed good in Group B, but there were no significantdifferences in image quality between the two groups (P＝0.33).Conclusions: Contrast media with the concentrations of270mgI/ml and300mgI/ml does not result in the different image qualities in abdominal CTA onrabbits.