The vein of Galen is located deep inside the brain. It is also called the great cerebral vein. It drains the blood from the brain into the venous system to carry back to the heart. Sometimes a malformation may form during the development of this venous system in the fetus prior to birth.  This results in an enlarged vein that receives high-flow blood directly from some to the arteries in the brain.  It usually occurs either congenitally (from birth) or as a result of another anomaly within the brain such as another arteriovenous malformation (AVM) or an arteriovenous fistula (AVF.

In children, vain of Galen malformations are usually congenital. In these cases it is also associated with other medical problems. As a result of the high blood flow in the brain, newborns may develop congestive heart failure and hydrocephalus (fluid on the brain). In adults, this usually presents with a brain bleed or some neurologic deficit such as extremity weakness or a focal paralysis.

Decisions regarding treatment are best discussed with a cerebrovascular neurosurgeon.  Depending upon the size, age of the patient, presence of congestive heart failure, and type of arterial connections, treatment may be advised.  Typically, these lesions are treated endovascularly (from within the blood vessels) by blocking the connections between the arteries and the venous malformation. 

Lindsey Parker PA-C and Justin F. Fraser M.D.