How do you quantify noncalcified plaque?

The ability of multislice computed tomography (MSCT) to visualize not only lumen but also coronary plaques is recognized as an attractive advantage of MSCT over conventional coronary angiography. In particular, the fact that during the administration of contrast not only calcified plaques but also noncalcified plaques can be identified has received enormous interest. Retrospective studies have shown an association between plaques containing noncalcified components and presentation with acute coronary syndrome. Accordingly, these observations have led to the notion that noncalcified plaque may play a role in the development of coronary events. However, whereas quantification of the amount of calcified plaque is highly standardized, no validated approach to quantify noncalcified plaque is currently available. To translate the observation of noncalcified plaque into clinically and potentially prognostically relevant data, several issues need to be considered about the identification and subsequent quantification of noncalcified plaque.