ABSTRACT
This chapter examines the rationale, technique, and interpretation of intravascular ultrasound (IVUS) and virtual histology (VH) -IVUS imaging in diagnostic, therapeutic, and research applications. The IVUS transducer converts electrical energy into acoustic energy through a piezoelectric crystalline material that expands and contracts to produce sound waves when electrically excited. The recognition of an artifact during IVUS acquisition is critical, as it may interfere with image interpretation and measurements. Standard IVUS image acquisition is performed after the administration of anticoagulation. The most common imaging artifacts are ring-down, nonuniform rotational distortion (NURD), and reverberations. Validation studies have characterized the appearance of normal coronary arteries by IVUS, demonstrating three distinct tissue layers: the intima, media, and adventitia. VH-IVUS has been used to assess the effect of anti-atherosclerotic therapy on plaque composition. Spectral analysis of the radiofrequency IVUS signals, termed VH-IVUS, has led to a more detailed assessment of atherosclerotic plaque composition.
