Contribution of scanning electron microscopy and associated analytical techniques to the study of atherosclerotic disease.

Human carotid atheroma has been examined by scanning electron microscopy (SEM) utilizing both secondary and backscattered electron detectors and transmission electron microscopy (TEM) both at conventional and high voltage. Different cytochemical techniques have been used to map elastic fibers, proteoglycans, calcium, non esterified cholesterol. By immunocytochemistry the distribution of factor VIII related antigen and actin has been studied. With SEM it was possible to detect aspects of carotid plaques not appreciated when using other conventional techniques. With TEM some modifications of the structural and/or functional features of connective tissue macromolecules have been observed. The occurrence of anomalous collagen has been shown. The fine investigation of endothelial cells, smooth muscle cells and the intercellular matrix components has supplied information of particular morpho-functional significance, thus allowing the development of new ideas on the complex pathogenetic mechanisms of atherosclerosis and suggesting some important anatomo-clinical correlations.