[Lesions of the motor cortex in amyotrophic lateral sclerosis]

The lesions of the spinal cord and the medulla in ALS, have been known for a long time. However the existence of cortical lesions in this disease, and their description, remain debated questions. This study deals with ten anatomical cases of ALS, with a special attention to the precentral gyrus. Three kinds of lesions are described in most cases: a disappearance of Betz cells with shrinkage and ghost cells of some other neurons; principally a subcortical gliosis, and also a laminar spongiosis located in the second cortical layer. The value and the signification of these lesions, which are strictly located in the motor cortex, are discussed. This could be compared to diffuse cortical lesions which are described in some cases of ALS with dementia state.