The recent development and rapid expansion of new percutaneous vascular interventional devices designed to remove or remodel atherosclerotic plaque has been accompanied by equally strong interest in imaging modalities guidance systems to more accurately evaluate disease and better facilitate vascular interventions than traditional angiography. Although contrast angiography remains the standard for diagnostic evaluation of coronary and peripheral arteries, intravascular ultrasound has the potential to offer more precise information about vascular anatomy and disease. Intravascular ultrasonography has been able to provide specific information regarding vessel lumen and wall. Such information is not available by traditional diagnostic methods and may become essential in the future diagnosis, staging, and treatment of atherosclerosis.