INTRAVASCULAR ULTRASOUND IMAGING - A CURRENT PERSPECTIVE

Catheter-based intravascular ultrasound imaging has evolved from a research tool to a device that has received Food and Drug Administration approval. Although it is currently employed as an adjunct to contrast angiography in both the peripheral and the coronary circulation, the indications for its use and its clinical utility have yet to be defined. Much of the research on the technique has explored its qualitative and quantitative capabilities to improve the assessment of atherosclerotic vascular disease. There is the hope that this imaging technique may ultimately improve the performance of endovascular interventions. This review describes the development of the technology from early in vitro validation studies to its present use in human subjects. Whenever possible, studies that validate the findings (that is, by comparison with histopathology results) of intravascular ultrasound are emphasized. Although there is great promise for this technology, limitations such as loss of image quality in severely diseased or heavily calcified vessels hinder its use. The application of imaging with endovascular intervention, imaging of intracardiac structures and the pulmonary circulation and new techniques such as computer image analysis are discussed.