Neurovascular Malformations in the Fetus and Neonate.

Vein of Galen malformations are the most common congenital neurovascular malformation and are a type of choroidal arteriovenous fistula involving the midline primitive choroidal venous circulation. The arteriovenous shunt zone of a VOGM may directly involve the embryonic precursor of the vein of Galen and/or its tributaries within the 3rd ventricle tela choroidea. Dural sinus malformations are characterized by dilated intracranial dural venous sinuses, some of which acquire multifocal arteriovenous shunts within the dural walls of these overgrown venous sinuses.Pial arteriovenous fistulae are high-flow shunts representing direct arterial to venous communication of pial blood vessels, with no definable nidus.