Usefulness of the intravascular ultrasonography (IVAS) in percutaneous transluminal angioplasty

Intravascular ultrasonography (IVUS) is a new imaging modality which allows high-resolution cross-sectional imaging of the arterial wall. We report IVUS of the commom carotid and vertebral arteries before and after percutaneous transluminal angioplasty (PTA) and stent placement in tow patients. MATERIALS AND METHODS：IVUS was performed using a 2.9F over-the-wire catheter system (Cardiovascular Imaging System, Ultra Cross 2.9) with a 30 MHz 2-D rotating mirror IVUS probe. This catheter was inserted through a 6 F sheath before and after PTA; a guide wire was used to pass it through the stenosis. The structure of the wall and the lumen were observed in real time. The images were stored on a videotape. RESULTS：The lesions of the patients were successfully observed by IVUS. Valuable information could be obtained about plaque constitutions and the cross-diameter of stenosis. The lesions were successfully dilated with PTA and stent placement. The attachment between the stent and the wall was confirmed by IVUS. No complications were apparent during or after the procedures. CONCLUSION：IVUS is a useful modality of intravascular intervention. It provides valuable information about atherosclerotic plaque constitutions, the degree of stenosis and the effect of intravascular intervention.