64层螺旋CT冠状动脉成像中优化对比剂注射技术对图像质量的影响

The evaluation of image quality using optimized low-dose contrast injection protocols on 64-slice spiral CT in coronary artery angiography

目的:比较常规固定对比剂注射方案和依据患者体重选择对比剂用量和流率技术对64层螺旋CT冠状动脉成像质量的影响。方法:研究中分别采用两种不同的对比剂应用方案,方案1:固定对比剂用量(70ml Iopamidol 370),方案2:依据患者的体重选择对比剂用量(0.8ml/kg)。100位行前瞻性心电门控冠状动脉检查的患者随机分为2组(50人/组),分别采用上述不同的对比剂方案。对横断面图像、多平面重组图像的图像质量进行评价(5分优,1分差),并选择冠状动脉不同节段处测量对比剂增强水平。统计分析两种方案下的图像质量、对比剂增强水平和对比剂用量。结果:方案1和方案2条件下的图像质量评分分别为4.17±0.23和4.24±0.18,无统计学差异(P>0.05)。对比剂平均增强水平存在统计学差异,方案1增强水平为(446±75)HU,而方案2为(387±69)HU。对比剂用量同样存在统计学差异,分别为70ml和53.1ml。结论:与固定对比剂应用方案相比,在冠状动脉成像中依据患者体重选择对比剂用量技术可以获得令人满意的图像,能够显著降低对比剂的用量,同时有助于获得更佳并且更为一致性的对比剂增强水平。

Objective：To compare the effect of a fixed contrast material injection dose protocol and a dose tailored to patient body weight injection protocol on 64-row MSCT in coronary artery angiography.Methods：Two contrast material injection protocols were applied in this study： protocol 1-a fixed contrast material dose（70 ml of Iopamidol 370）;protocol 2-a dose tailored to the patient＇s body weight（0.8 ml/kg）.Prospective ECG-triggered cardiac CTA was performed in 100 patients（50 patients in each protocol）.The image quality of multiplanar reformation（MPR） was analyzed using 5 point scoring（5： Excellent;1： poor）,and the mean cardiac artery enhancement was also measured.Statistical t test analysis on image quality score,enhancement and dose of contrast material was performed.Results：The mean image quality scores of protocol 1 and protocol 2 were 4.17±0.23 and 4.24±0.18,respectively.There was no statistically difference（P〉0.05）.The mean enhancement was（446±75） HU with protocol 1 and（387±69） HU with protocol 2,indicating significant statistical difference.The mean contrast material dose showed statistical difference between protocol 1（70 ml） and protocol 2（53.1 ml）.Conclusion：The dose tailored to patient body weight injection protocol can provide satisfactory quality and has the potential to significantly reduce contrast material injection dose compared with fixed contrast material injection dose protocol.And it is very useful for obtaining better,homogeneous and consistent contrast enhancement.