After brief considerations on the symptomatology and ethiopathogeny of megadolichobasilar, five cases of this vascular anomaly are presented. Agreeing with the majority of the papers on the subject, the age of the patients was between the fourth and the sixth decades, all of them presenting arterial hypertension of long duration and advanced atherosclerosis; the neurological findings were varied, having in common the fact of an abrupt (ictal) beggining. The angiographic study of the vertebrobasilar system was basic in the diagnosis in every case.