目的评价双源CT双向法下肢静 脉造影(CTV)的可行性及临床应用价值。 方法 共63例患者进行了CTV检查。双向法 CTV是经左侧肘静脉和足背静脉分别注入 造影剂，在第1次注射造影剂2.5分钟后启 动扫描。间接法CTV是经肘静脉注射造影 剂，注射造影剂2.5分钟后启动扫描。直 接法CTV是经患侧足背静脉注入稀释的造 影剂60ml，速率1.5ml/s，在注射造影剂1 分钟后启动扫描。扫描方案统一采用双能 量扫描法，电压为100kV和Sn140kV，电压 配比比例为0.5，CareDose4D法自动追踪 电流，准直器宽度128x0.60mm，球管旋转 一周0.33s。结果 63例DVT患者，108条下 肢，324个血管节段，DSA在125个节段中 检出血栓，CT共检出121个血栓，CT的血 栓总检出率96.80%。双向法CTV可以提高 静脉对比度并消除边流效应，图像质量优 于间接法和直接法CTV。结论 双向法CTV 是一种可行的下肢静脉造影方法，可以弥 补间接法和直接法的不足。

Objective To evaluate the feasibility and clinical value of the bidirectional lower extremity venography (CTV) with dual-source CT. Methods 63 patients underwent CTV checks.In the bidirectional CTV, contrast agent was injected via the left cubital vein and dorsal venous, respectively, scanning was started after 2.5 minutes of the beginning of injection. In indirect CTV the contrast agent was injected through the cubital vein, the scan was started after 2.5 minutes of the beginning of injection. In the direct CTV, 60ml diluted contrast agent was injected via the diseased dorsal vein, the rate 1.5ml/ s, scanning started after 1 minutes of the beginning of injection.Ddual-energy scanning protocol was uniformly applied with the voltage ratio 0.5 of 100kV and Sn140kV, CareDose4D automatically tracking total of 108 lower limbs and 324 vascular segments. Results DVT were detected in 125 segments with DSA and in 121 segments with CT, current, collimator width 128x0.60mm, tube rotation 0.33s. 63 cases with DVT have a the total detection rate of DVT with CT was 96.80%. The bidirectional CTV can improve the contrast of veins and eliminate the side flow effects, image quality is better than the indirect and the direct CTV. Conclusion The bidirectional CTV is a feasible method of lower extremity venography and can compensate for disadvantages of the indirect and direct method.