[Variants of collateral cerebral circulation in moyamoya disease].

Neoangiogenesis is a natural compensatory mechanism in moyamoya disease designed to maintain brain perfusion under reduced cerebral blood flow. Predominant intra-intracranial collaterals are associated with ischemic and hemorrhagic events. Timely restructuring on extra-intracranial ways of collateral circulation prevents adverse manifestations of disease. Assessment and understanding of collateral circulation in patients with moyamoya disease create the prerequisites for substantiating the method of surgical treatment.