Arterosclerotic Diseases

Abstract

In radiologic examinations, only macroscopic arte-riosclerotic changes are demonstrable. Luminal nar-rowings less than 50% are defined as plaques and narrowings exceeding 50% as stenoses, while further partial differentiation is possible based on the structure of the artery’s inner surface (Fig. 25.1). Plaques are more easily identified in small arteries than in major arteries due to the lower concentration of contrast medium. In the aorta, plaques appear as irregularities of the intima, but a high concentration of contrast agent can obscure small changes of the vascular wall. Smaller amounts of contrast agent, as are used in the transparent technique’ using Med-ichrome film, have demonstrated better detection of plaques (Zeitler and Hüring 1972). Irregularities and arteriosclerotic plaques may become a source of emboli. Prior to establishing therapy and in order to prevent emboli, ulcerating atherosclerotic plaques and associated small thrombi need to be identified (Schmitt et al. 1971).