The pathological study of the cerebral hemispheres and visual pathways in 32 cases of disseminated sclerosis, including 15 cases in which the retinal structures were investigated, lead us to point out: 1) the high frequency of histological lesions of the optic nerves, tracts and radiations; 2) the lack of correlation between the extent of demyelination of the optic nerves and the impairment of visual acuity that is mainly related to axonal lesions; 3) the relative high frequency of pathological sheathing of retinal veins; and 4) the high proportion of shadow plaques in the cerebral hemispheres in cases with clear-cut relapses and remissions.