Establishment Of Acute Subsegmental Pulmonary Embolism Model In Porcine Experiment And The Radiology Diagnostic Comparison

Objectives: 1.To establish a porcine model of acute subsegmental pulmonary embolism which is suitable to study imaging diagnosis and to evaluate the technique feasibility and stability; 2.To compare the visibility of subsegmental pulmonary emboli by different slice thickness reconstruction using multislice spiral CT pulmonary angiography.3.To compare multislice spiral CT to digital subtract pulmonary angiography for the detection of subsegmental pulmonary emboli by using a cast of porcine pulmonary vessels as an independent gold standard. Methods: 1. Some polyvinyl chloride emboli (the diameter of the emboli was 2-3mm)were injected into the right external jugular vein in five porcines. DSPA and CTPA were performed respectively before and after pulmonary embolism. These porcine were put to death after pulmonary embolism within 24 hours. The pulmonary casts were made of porcine lungs in vitro by using some resin, of which the concentration was about 32.8%.2. 5 porcine were underwent CT pulmonary angiography with 1.0mm collimation. Three different slice thickness were reconstructed from the raw data for each porcine: 1.0mm/0.5mm(slice thickness /increment,group A), 2.0mm/1.0mm( group B),3-0mm/1.5mm(group...