RESUMO
Objective To evaluate the effect on threshold of triggered angiographic acquisition by different iodine flow rate on renal artery CTA using Smart Prep tracking technique.Methods A total of 420 patients were randomly divided into A-D group with iodine flow rate of 0.90 gI/s,1.11 gI/s,1.20 gI/s,1.48 gI/s on average respectively.And each group were divided 7 subgroups with threshold 140-＜150 HU,150-＜ 160 HU,160-＜ 170 HU,170 ＜180 HU,180 ＜190 HU,190-＜200 HU,200-210 HU respectively.The quality of the images were graded from 1 5 by 2 radiologists.The best image quality subgroups were achieved,and the scores were compared among the best image quality subgroups.Results Image quality of renal CTA in each group were best performed with a threshold of 170-＜ 190 HU,160-＜ 190 HU,170-＜ 180 HU,160-＜ 180 HU respectively.When the threshold were 170-＜180 HU,image quality were good with all iodine flow rate groups.There was no significant difference among the scores of the best image quality subgroups (all P＞0.05).Conclusion Different iodine flow rate with appropriate threshold can acquire better image quality of renal CTA.
