Three-dimensional forward-viewing intravascular ultrasound imaging of human arteries in vitro

The aim of this work was to investigate the suitability of a novel forward- viewing intravascular ultrasound (IVUS) technique for three-dimensional ima ging of severely stenosed or totally occluded vessels, where the convention al side-viewing IVUS systems are of limited use. A stiff 3.8 mm diameter fo rward-viewing catheter was manufactured to scan a 72 degrees sector ahead o f its tip. Conical volume data were acquired by rotating the catheter over 180 degrees by means of a motorised mechanical system. Operating at 30 MHz, the catheter was integrated with an IVUS scanner and a radiofrequency data acquisition system. Postmortem carotid and femoral arteries were scanned i n vitro. Correlation of the reconstructed images with histology demonstrate d the ability of this forward-viewing IVUS system to visualise healthy lume ns, bifurcations, thickened atherosclerotic walls and, most importantly, se vere and complete vessel occlusions. A rotating-sector forward-viewing IVUS system is suitable for anatomical assessment of severely diseased vessels in three dimensions.