Comparative imaging techniques and models.

Abstract

The explosion of high-resolution imaging technology in recent years has led to the increasing problem of choosing imaging modalities appropriate to specific clinical questions. In terms of structural information, for example, the relative benefits of ultrasound versus magnetic resonance imaging versus computed tomography scanning are often readily apparent, but in the related area of flow velocity imaging, difficulties may arise. These are perpetuated by the relative lack of information on the fundamental display characteristics of these imaging techniques. Much of this essential information can be acquired from in vitro modeling of the pressure and flow characteristics of a variety of pathologic lesions. The information obtained from such experimental investigation can provide a basis for a more rational approach to the interpretation of these imaging modalities in the clinical setting. We review the recent role of in vitro modeling for enhancing our understanding of the display characteristics of various imaging technologies, with particular emphasis on Doppler ultrasound and color Doppler flow mapping where in vitro modeling has been most extensively studied.