A rare hereditary condition, called vein of Galen malformation, causes high-pressured blood to be pumped from arteries into veins. The veins aren't meant to handle such pressure and can rupture, spilling blood into the brain.

The effect is like trying to connect your backyard garden hose to a fire hydrant the veins cannot withstand such high pressures from pumping arteries," explained study corresponding author Kristopher Kahle, of Yale University.

Galen malformation

He's an assistant professor of neurosurgery, pediatrics, and cellular and molecular physiology. A vein of Galen malformation (VOGM) is a rare but particularly severe type of arteriovenous malformation (AVM) that develops before birth and is diagnosed in infants and young children. It affects the “great cerebral vein,” also known as the vein of Galen, which is one of the large veins that return blood from the brain to the heart.

The condition is sometimes referred to as a vein of Galen aneurysmal malformation (VGAM). A thread of Galen malformation can be fatal, but the prognosis has dramatically improved with newer endovascular techniques performed by highly trained experts.

For the study, Kahle's team conducted genetic analyses of 55 children with vein of Galen malformation and their parents. The investigators identified some genetic mutations associated with the condition.One mutation is in a gene called EPHB4, which plays a significant role in the development of the vascular system, the study authors reported.

The researchers also discovered that many parents who carry mutations of this gene had skin lesions caused by vascular irregularities. This information might help doctors diagnose vein of Galen malformation before a baby suffers a brain bleed, Kahle and his colleagues said in a Yale news release. Currently, the best treatment is a minimally invasive catheter procedure, but only a few facilities in the United States can perform the operation, the researchers said.

However, there are drugs to treat other conditions caused by genetic disruptions identified in the study. Those drugs might prove helpful in managing children with vein of Galen malformation, Kahle said.

Post-hemorrhagic hydrocephalus (PHH), characterized by a buildup of cerebrospinal fluid (CSF) following bleeding of blood vessels in the brain, affects one in a thousand children and is currently treated almost exclusively by the surgical insertion of shunts in the brain.