Vein of Galen Malformation

A vein of Galen malformation is a rare and serious blood vessel abnormality in your baby’s brain. It’s a type of arteriovenous malformation (AVM) that happens during fetal development.

When a fetus develops as expected, smaller blood vessels fuse together deep within the brain to form the vein of Galen. In a vein of Galen malformation, your child’s arteries connect directly to the vein. This means the arteries push their high-pressure blood directly into the vein without the usual capillary bridges that slow down blood flow.

But veins don’t have the wall strength to carry high-pressure blood. As a result, the vein of Galen swells and can bleed. Your child’s heart has to work on overdrive to manage the increased blood flow and pressure.

VOGM is life-threatening if untreated. It’s usually suspected during pregnancy and confirmed after your child is born. A healthcare provider will treat this condition as soon as possible to prevent complications.

What is the vein of Galen?

The vein of Galen (great cerebral vein) is a major blood vessel in your brain. It’s located deep inside your brain, above the brainstem. It’s responsible for draining blood from certain structures in your brain, like white matter. It helps your blood circulate as expected.

What are the types of vein of Galen malformations?

There are two types of VOGMs:

• Choroidal: Several arteries connect to the vein. This is the most common type and most severe.
• Mural: There are fewer connections to the vein.

Vein of Galen malformation symptoms

Early signs and symptoms of a vein of Galen malformation among infants may include:

• Growth faltering
• Large head size (macrocephaly)
• Seizures
• Swollen, visible veins on their scalp

Older children who have less severe cases and don’t receive a diagnosis as an infant may have developmental delays and persistent headaches.

What are the complications of a vein of Galen malformation?

Severe and life-threatening complications of VOGMs may include:

• Brain bleed
• Congestive heart failure
• Hydrocephalus
• Pulmonary hypertension
• Stroke
• Subarachnoid hemorrhage

Vein of Galen malformation causes

The exact cause isn’t well known. Researchers suggest the RASA1 or EPHB4 genetic variants may be involved.

It’s not possible to know for certain the genetic outcomes of a pregnancy before it happens. But a genetic counselor can help you learn more about your risk of having a child with a genetic condition. And they can help you learn more about how a condition might affect you and your family.

Healthcare providers do know that there’s no way to prevent this condition. There isn’t anything you did — or didn’t do — during pregnancy to cause it.

How a doctor diagnoses a vein of Galen malformation

A healthcare provider may suspect a vein of Galen malformation during a pregnancy ultrasound in the third trimester. The vein of Galen should look like a tube. Your provider may notice the tube instead has a large, ballooned section on it where it expanded.

After your baby is born, your child’s provider will perform a physical exam and review their symptoms. Their provider may use a stethoscope to listen to the sound of blood flow in your child’s head. They’ll listen for a pulsating sound (bruit) that may indicate that blood is moving faster than expected.

A computed tomography (CT) or magnetic resonance imaging (MRI) confirms a diagnosis. Imaging tests will give your child’s provider a better look at the malformation and other surrounding brain structures. They can review where it is and how big it is. These tests can also help your child’s care team plan for treatment.

How is a vein of Galen malformation treated?

Embolization treats a vein of Galen malformation. This is a surgical procedure to stop blood flow to the arteries that feed into the vein. Here’s what you could expect during embolization:

1. An anesthesiologist will give your child general anesthesia. They’ll be asleep during the procedure.
2. A provider will make a very small incision — usually in your child’s groin — to insert a flexible tube (catheter) into your child’s artery.
3. They’ll carefully move the tube through your child’s artery to the treatment area in their brain.
4. A provider will inject an embolic agent (a material to close the openings) to stop blood flow in a specific area.
5. They’ll remove the catheter and bandage the small incision.

In some cases, surgery may be delayed until your child reaches at least 6 months to 1 year of age. This is to make sure that certain areas of your child’s body develop enough to handle the procedure. Your child will receive supportive care or medications to manage their symptoms. This also prevents complications before surgery.

When should I take my child to see a healthcare provider?

If your child has a VOGM, their provider will let you know what symptoms to look out for, especially when they’re cleared to leave the hospital after treatment. This could include:

• Behavior changes (fussy or lethargic)
• Fever
• Seizures
• Swelling
• Vomiting

What’s the prognosis for a vein of Galen malformation?

With endovascular treatment (embolization), many children have an improved outlook. Your child’s care team will explain the risks and possible complications of the procedure so you can make an informed decision about their treatment.

If treatment is successful, your child might need another procedure in the future or close monitoring as they grow. This may include several follow-up appointments with specialists, in addition to their regular check-ups with a pediatrician. Some children don’t experience any long-term complications after receiving treatment, but this varies from child to child.

Vein of Galen malformation life expectancy

Treatment may significantly improve your child’s life expectancy. Because without it, some types of VOGM are fatal.

A lot of factors go into determining your child’s life expectancy, like the severity of the condition and whether surgery is a safe option. Your child’s situation may or may not reflect statistics. Their healthcare provider is the best person to speak with to learn more about what you can expect.