For the evaluation of atherosclerosis in carotid arteries up to now sonographic measurements of plaque burden are used. This method has advantages for investigation of carotid arteries since this region is easy accessible for this investigation. However, it does not allow evaluation of the vessels which are remote from the body surface, as, for instance, coronary arteries. A method for non-invasive reliable evaluation of such arteries is needed. Also the distinction between vulnerable and stable plaque has a great clinical relevance. A quantifiable method for the determination of the effects of new therapeutic approaches would be highly appreciated.