【摘要】 目的探讨应用小剂量团注测试扫描技术在肺动脉CT血管成像中降低对比剂剂量及浓度的可行性。方法将60例可疑诊断肺栓塞需肺动脉CT成像检查的患者随机分为两组:常规组30例,采用智能对比剂追踪法。个体化组30例,采用小剂量团注测试扫描技术。收集各个动脉段的评价CT值,对所有图像采用优化的5分法进行比较。结果个体化组使用的平均对比剂的剂量显著低于常规组(41.8 ml vs.80ml,P=0.021)。个体化组肺动脉主干(361.0±18.1 vs.344.3±19.1),肺动脉S1段(293.30±15.4 vs.269.88±17.5)及S10段(306.40±14.3 vs.282.5±20.3)的平均增强CT值与常规组比较差异均无统计学意义(P>0.05)。但个体化组升主动脉的平均增强CT值明显低于常规组(169.10±32.1 vs.92.90±31.9,P=0.04)。图像5分法评分盲法评价的总体结果在常规组与个体化组差异无统计学意义(P>0.05),但个体化组的5级图像比例明显高于常规组(70%vs.43.3%)。结论小剂量团注测试扫描技术可以使用低剂量低浓度的对比剂获得不劣于传统智能对比剂追踪技术的高质量肺动脉CTA图像。更多还原

【Abstract】 Objective To investigate the feasibility of low dose and concentration contrast medium for dual-source computed tomography pulmonary angiography(CTPA). Methods Sixty patients with suspicious diagnosis of pulmonary embolism were prospectively randomized divided into 2 groups. Conventional group had 30 patients who received CT scan using the bolus tracking technique with 80 ml high concentration contrast medium(Iopromide 370 mg I/ml) injected and followed by 30 ml saline at a speed of 5ml/s. Individualized group had 30 patients who received CT scan using the low dose bolus test technique, and the delay time was conformed according to the peak time of pulmonary artery which was calculated using the time-tensity curve with 15 ml contrast medium of low concentration(Iopromide 300 mg I/ml) injected and followed by 30 ml saline at a speed of 5 ml/s. The doses of low concentration contrast medium were calculated according to the BMI of each patient. Image quality was assessed using the grades from 1 to 5. Results The mean dose of contrast media in individualized group was significantly lower than that in conventional group(41.8 ml vs. 80 ml, P=0.021). The mean enhanced CT values were similar between conventional and individualized groups in main pulmonary artery(361.0±18.1 vs.344.3±19.1), S1 segment(293.30±15.4 vs. 269.88±17.5) and S10 segment(306.40±14.3 vs. 282.5±20.3) of pulmonary artery(all P>0.05). However, the mean enhanced CT value of aorta was significantly lower in individualized group than that in conventional group(169.10±32.1 vs. 92.90±31.9, P=0.04). The grades of image quality were comparable between conventional and individualized groups(P>0.05), but the percentage of 5 grade image was higher in individualized group than conventional group(70% vs. 43.3%). Conclusions The dose and concentration of contrast could be reduced by the low dose test bolus technique for dual-source computed tomography pulmonary angiography with high image quality.更多还原