Arteriovenous malformation of the vein of Galen in children.

Arteriovenous malformation of the vein of Galen (VGM) is a unique vascular anomaly in children. Its extra parenchymal location allows for aggressive endovascular treatment. Depending on the age of the child, the clinical presentation of VGM varies from congestive heart failure to hydrocephalus. The deleterious consequences to the brain depend on many factors, the most important of which is the volume of blood shunting through the malformation and away from the brain parenchyma ("steal" phenomenon). High flow in a fetus with a developing brain will lead not only to brain ischemia but also to multiple organ failure. At the other end of the spectrum, a small malformation can be well tolerated. Treatment should be tailored to each individual case.