Compared study of imaging in lower extremity arterial stenosis or occlusion

Objective To investigate the value of DSA, CTA in diagnosis of lower extremity arterial stenosis or occlusion. Methods 21 confirmed patients of lower extremity arterial stenosis or occlusion were received DSA and CTA examinations. The two methods were compared in the definition, grade of arterial lumen stenosis, sensitivity, specificity, accuracy and bypass circulation. Results CTA was better than DSA in definition of artery, but with no significant difference(P≥0.05). CTA was not conformed to DSA in 2 cases of iliac artery, 4 cases of popliteal-femoral artery and 4 cases of tibial-fibular artery. Compared with DSA, CTA over-estimated the degree of stenosis so as with more false positive rate. The sensitivity, characteristics and accuracy of CTA decreased with the degree increase of arterial stenosis, but with no significant difference(P≥0.05)compared with DSA. CTA had the worse image of bypass circulation with the degree increase of arterial stenosis. It would increase the positive rate of bypass circulation and distal artery of occlusion by increasing contrast dosage and exposure time in DSA. Conclusion CTA is used increasely in primarily detecting lower extremity arterial stenosis or occlusion, but DSA is still the first choice of diagnosis.