造影剂剂量对多层螺旋CT门静脉成像质量的影响

The optimal dose of the contrast media for spiral CT portography

目的探讨造影剂剂量对多层CT门静脉成像(SCTP)质量的影响。方法选择健康非肝病患者40人,其中20人体重低于60 kg,20人体重高于70 kg,给予固定剂量90 ml造影剂。再选取非肝硬化、肝硬化无腹水、肝硬化中等量以上腹水患者各60人分3组,每组20人,分别给予1.5ml/kg、2.0ml/kg、2.5ml/kg造影剂,注射流率为4ml/s,其他参数不变,比较不同体重及疾病程度状态下,造影剂剂量对门脉期扫描成像质量的影响。结果给与固定剂量90 ml造影剂,门静脉-肝实质密度差在体重低于60 kg组明显高于体重高于70kg组(P<0.05)。分别给予1.5ml/kg、2.0ml/kg、2.5ml/kg造影剂时,门静脉主干和肝实质密度随造影剂剂量增加而升高,但2.0ml/kg组和2.5ml/kg组门静脉-肝实质密度差无显著性差异(P>0.05),两者均与1.5ml/kg组存在显著性差异(P<0.05)。应用相同剂量造影剂时,肝硬化腹水患者门静脉-肝实质密度差低于非肝硬化和肝硬化无腹水患者(P<0.05)。应用2.0ml/kg和2.5ml/kg造影剂,肝硬化腹水组的门静脉-肝实质密度差无显著性差异,两者均与1.5ml/kg组存在显著性差异(P<0.05)。此外门静脉分支显影质量以及侧枝静脉显示情况在2.0 ml/kg组也优于其他两组。结论体重及肝脏疾病严重程度影响门静脉强化程度,通过体重计算造影剂用量对于保证门静脉成像质量至关重要,采用2.0 ml/kg造影剂能够保证良好的门静脉强化效果。

Objective To investigate the optimal dose of the contrast media in SCTP. Methods 40 healthy patients were divided into 2 groups according to their body weight （20 cases in group A with weight below 60kg, 20 cases in group B with weight over 70kg）. They all received 90ml contrast media at a rate of 4.0 ml/sec in the contrast-enhanced CT examination. And non-cirrhosis cases, liver cirrhosis without ascites cases and liver cirrhosis with ascites cases were selected respectively, 60 patients in each group. Then, the patients of each group were randomly divided into 3 sub-groups, 20 cases in each of them, which respectively received 1.5ml/kg,2.0ml/kg、2.5ml/kg contrast media at a rate of 4.0 ml/sec in the contrast-enhanced CT examination. The effect of the dose of the contrast material on the imaging quality of portal vein system in patients with different weight and different state of illness was analyzed. Results In 40 healthy patients, the density difference between portal vein and hepatic parenchyma was significantly higher in Group A than in Group B （P〈0.05）. When we gave different dose of contrast material respectively with 1.5ml/kg,2.0ml/kg,2.5ml/kg, the density of portal vein and hepatic parenchyma increased with the dose of the contrast media, but the density difference between portal vein and hepatic parenchyma showed no difference between using 2.0ml/kg and 2.5ml/kg contrast media （P 〉 0.05）, and both of them showed significant difference while using 1.5ml/kg contrast media （P 〈 0.05）. With the same dose of contrast media, the density difference between portal vein and hepatic parenchyma in the patient of liver cirrhosis and ascites was much lower than in the non-cirrhosis cases and in the patients of cirrhosis without ascites （P 〈 0.05）. In the patients with cirrhosis and ascites, the density difference between portal vein and hepatic parenchyma showed no difference between using 2.0ml/kg and 2.5ml/kg contrast media （P 〉 0.05）, and they both had significant difference when using 1.5ml/kg contrast media （P〈 0.05）. Besides these, the imaging quality of portal vein branches and collateral vessels were better in 2.0ml/kg group than others. Conclusion The patient＇s body weight and the state of liver disease influenced the extent of portal vein enhance- ment. To calculate the dose of contrast media according to patient＇s weight is crucial for ensuring the imaging quality of portal vein system. 2.0ml/kg contrast media can provide a better effect.