Characterizing arterial plaque with optical coherence tomography

Many imaging technologies have been pivotal in the reduction of mortality associated with coronary artery disease over the last 50 years. However, there are several areas where coronary disease could benefit from high-resolution imaging. Recently, optical coherence tomography (OCT) has been introduced for micron scale intravascular imaging. OCT is analogous to ultrasonography, measuring the intensity of back-reflected infrared light rather than sound. First, its resolution, at 4 to 20 microm, is higher than that of any currently available imaging technology. Second, acquisition rates are near video speed. Third, unlike ultrasonography, OCT catheters consist of simple fiber optics and contain no transducers within their frame. This makes imaging catheters both inexpensive and small, the current smallest cross-sectional diameter being 0.014 inches. Fourth, OCT systems are compact and portable. Finally, it can be combined with a range of spectroscopic techniques. This article reviews the application of OCT to intracoronary imaging.