[Role of vertebral artery hypoplasia in the pathogenesis of cerebral circulatory disorders].

Clinico-angiographic comparison of 30 cases of vertebral artery hypoplasia was carried out. It was found that the artery hypoplasia was often combined with a lateral shift of the artery opening, convolute shape of the major brain vessels, and functional reconstruction of the Villisian circle, a transitional type of the posterior trifurcation. It was ascertained that the vertebral artery hypoplasia, not being a pathogenetic factor itself, can play a negative role in cases of occlusion of a major brain vessel, since it limits the potentialities of compensatory blood circulation.