[New morphological data on multiple sclerosis].
The brain from 6 patients who died of multiple sclerosis was studied with MR tomography (MRT), macroscopy, light (CD 3, CD 20, LCA antigens) and electron microscopy (EM). Typical foci of demyelinization (plaques) were found in all cases. Alterations of brain arteries were found particularly in arteries of narrow lumen--with disturbance or even absence of elastin and muscle layer. Up to 30% of the vessels were surrounded by microcavities. Perivascular infiltrates consisting primarily of T lymphocytes were observed around the vessels (up to 70% of all vessels). This indicates the importance of vascular changes in the disease pathogenesis. Four variants of demyelinization (plaques) are distinguished depending on the degree of destruction of myelin, axons and glia. Two types of cells were found in the plaques with most pronounced changes: astrocytes and newly formed oligodendrocytes. Classification of plaques is suggested.