目的 分析64排螺旋CT低剂量对 比剂在CT肺动脉血管造影检查中的应用可 行性。方法 选取我院2012年11月至2014 年11月临床怀疑为肺动脉栓塞的患者64 例，随机抽签分为两组，每组32例，低 剂量组使用30mL对比剂，常规剂量组使 用70mL对比剂。比较两组患者肺血管强 化CT值、图像噪声、信噪比、对比噪声 比、主观图像质量评分及不良反应发生 率，比较两组诊断肺栓塞的灵敏度、漏诊 率、特异度和误诊率。结果 常规剂量组 肺静脉血管强化CT值较低剂量组显著较 高(P＜0.05)；低剂量组不良反应发生率 为12.5%较常规剂量组43.75%显著较低(P ＜0.05)。结论 在CT肺动脉血管造影检查 中应用64排螺旋CT低剂量对比剂可以满足 临床诊断需求，在图像质量以及对肺栓塞 诊断的准确度、敏感度和特异度方面与使 用常规剂量无显著差异，且患者不良反应 发生率降低，值得临床应用推广。

Objective To analyze feasibilityof application of 64-slice spiral CT low dose contrast medium in CT pulmonary angiography. Methods 64 patients suspected clinically as pulmonary embolism in our hospital from November 2012 to November 2014 were divided by random lot method into two groups, 32 cases in each group, low dose group used 30mL contrast medium, routine dose group used 70mL contrast medium. Vasa publica enhanced CT value, pattern noise, signal-to-noise ratio, contrast-tonoise ratio, subjective image quality score and incidence of adverse reactions in the two groups were compared, sensitivity, rate of missed diagnosis, specificity and misdiagnosis rate in the diagnosis of pulmonary embolism in the two groups were compared. Results Pulmonary vein vessel enhanced CT value in routine dose group was significantly higher than low dose group(P<0.05), incidence of adverse reactions in low dose group was 12.5%, which was significantly lower than routine dose group (43.75%) (P<0.05). Conclusion Application of 64-slice spiral CT low dose contrast medium in CT pulmonary angiography can meet the demand of clinical diagnosis, there is no significant difference in image quality, accuracy, sensitivity, specificity in the diagnosis of pulmonary embolism compared with routine dose, decreases incidence of adverse reactions of patients, is worth using in clinical practice.