低流率团注高浓度对比剂在兔脑CTA成像中的效果

High concentration contrast media with low flow rate on the CTA imaging of healthy rabbits

目的探讨低流率团注高浓度对比剂在脑CT血管成像(CTA)中的可行性。方法18只新西兰白兔随机分为3组,实验组使用A方案(碘迈伦400 mgI/ml,流率0.5 ml/s);对照组分别使用B方案(300 mgI/ml,流率1.0 ml/s)或C方案(400 mgI/ml,流率1.0 ml/s),每次注射对比剂含碘量为0.5 g/kg体重,行脑CT同层动态扫描,获得兔大脑中动脉强化的时间-密度曲线。对比各方案兔大脑中动脉强化峰值到达时间(PT)及到达峰值时大脑中动脉的CT值。结果大脑中动脉平均强化峰值分别为(164.67±5.16)HU、(163.00±7.13)HU、(193.50±5.13)HU,C方案高于A、B方案(P<0.01),A、B方案之间差异无统计学意义(P=0.63)。三组方案测得大脑中动脉PT分别为5 s、5 s、4 s,C较A、B方案提前。结论在兔脑CTA扫描中,使用高浓度对比剂,可以大大降低注射流率而对血管强化效果无明显影响;在注射流率相同情况下,应用高浓度对比剂可使血管显示更清晰。

Objective To evaluate the feasibility of high-concentration contrast media（400 mgI/ml）with low flow rate in the CTA imaging of healthy rabbits.Methods Eighteen New Zealand white rabbits were randomly separated into three groups and underwent cerebral CT perfusion imaging with protocol A（400 mgI/ml,flow rate 0.5 ml/s）,protocol B （300 mgI/ml,flow rate 1.0 ml/s）,protocol C（400 mgI/ml,flow rate 1.0 ml/s）,respectively.The total amount of iodine for each injection was 0.5 g/kg weight.CT peak values of middle cerebral artery and the time when the artery reached the peak value（PT）of each protocol were acquired and compared statistically.Results The PT of three protocols was 5 s,5 s, 4 s respectively.The mean CT value of middle cerebral artery at peak time of group A（164.67±5.16）HU was higher than that of protocol B（163.00±7.13）HU and protocol C（[193.50±5.13]HU,both P〈0.01）,but the difference between protocol A and protocol B was not significant（P=0.63）.Conclusion Cerebral CTA imaging of healthy rabbits using high- concentration contrast media with low flow rate does not affect the visualization of vessels and the perfusion parameters. With same injection rate,high-concentration contrast media may improve the visualization of vessels.