[Paroxysmal phenomena in multiple sclerosis. Brain stem crisis].

The authors report three cases of multiple sclerosis which presented, during its course, paroxysmal attacks, also denominated brain-stem seizures. They review the literature with special reference to the incidence and the clinical forms of these paroxysmal phenomena, and they discuss the proposed pathogenic mechanisms. According to the authors, the literature review and the clinical picture of their cases, have shown a direct relation between these paroxysmal symptoms and a neighboring bout of the disease. They may also appear as an isolate "abortive bout". A partially demielinated lesion at brain-stem level, possibly by a transversely spreading ephatic activation, is suggested to explain the clinical phenomena.