Preliminary application of multi-slice CT direct venography in lower extremity vein / 中国医学影像技术

ABSTRACT

Objective To discuss the injective method, contrast agent concentration and delay time of MSCT direct venography in lower extremity vein, in order to make optimal venographic schedule. Methods Thirty-two patients with lower extremity vein diseases underwent MSCT direct venography in using different concentration and injective rate of contrast agent, and the images were analyzed. The displaying ability of MSCT direct venography in lower extremity vein segment was compared with that of X-ray venography in 22 patients. Results Blood flow correlation constructed defect was the main factor impacting image quality of CT venography in lower extremity. The image scores between the groups of injective rate 1.5 ml/s and the group of 2.5 ml/s were statistically different (χ~2=5.495, P=0.019), whereas no difference of image score was found between the group of concentration of 25% and 15% (χ~2=3.333, P=0.068). The displaying ability of CT and X-ray venography in anterior tibial vein, posterior tibial vein, popliteal vein and femoral vein was not statistically different (χ~2=2.095, P=0.148). For iliac vein, the displaying ability of CT outstripped that of X-ray venography (χ~2=8.324, P=0.004). Conclusion With the schedule of delay time 50 s, injective rate 2.5 ml/s and concentration 45 mgI/ml (nonionic 300 mgI/ml and diluted 15%), MSCT direct venography in lower extremity can acquire satisfactory image, and its displaying ability of iliac vein is better than that of X-ray venography.