Abstract
A demyelinating perivascular condition has been observed in the optic nerves of three cats, the lesions of which included the following features: thinly myelinated and demyelinated axons, few normal oligodendrocytes, astroglial scar tissue, lymphocytes, plasma cells, mononuclear phagocytic cells and lipid-laden cells. Also present were tubular inclusion bodies which had morphological features similar to the nucleocapsids of some paramyxoviruses. These lesions are compared with some other demyelinating diseases of the central nervous system, and similarities to the lesions of multiple sclerosis are suggested.