The anatomo-clinical study of 4 cases of infantile neuroaxonal dystrophy enables us: 1. (1) to describe its clinical features: the disease starts usually at the end of the first year of life after a normal early psychomotor development; severe hypotonia, arrest of mental development followed by a rapidly progressive dementia, optic atrophy, progressive appearance of hypertonia with a pyramidal syndrome, bulbar signs, sphincter disturbances, death between the ages of 4 and 10 years; 2. (2) to stress the main histological features of the disorder: presence of spheroid bodies in the grey matter with a clear-cut predominance in the sensory bulbo-spinal relay nuclei, multiple system atrophies (optic and pyramidal pathways, cerebellar cortex, posterior columns), diffuse sclerosis of the white matter, accumulation of neutral fats in the striatum and the pallidum, histiocytic proliferation in the splenic Malpighian follicles; 3. (3) to confirm, through electron microscopy, the localization of the spheroids in the axon terminals and the presynaptic endings; 4. (4) to attempt a correlation between the clinical features and the evolution of the lesions in the central nervous system. © 1972.