Signs and Symptoms

A vein of Galen malformation (VOGM) occurs when there is an abnormal connection between arteries and the deep draining veins. Normally, these arteries and veins are connected by capillaries, which monitor and slow blood flow through the brain, allowing for the exchange of oxygen and nutrients. However, because a VOGM does not have capillaries, the blood flow becomes very fast, making the heart work harder.

Heart failure is considered the most common symptom of VOGM. This is usually caused by the high level of abnormal blood flow through the VOGM, which can put great strain on an infant's heart.

A VOGM can also cause an infant to have abnormally rapid head growth during infancy. This is due to hydrocephalus -- the accumulation of excess fluid in the brain caused by interference with the normal drainage of the fluid produced by the brain, called cerebrospinal fluid.

Diagnosis

In some cases, a vein of Galen malformation (VOGM) may be detected by an ultrasound before a baby is born. However, in many instances the VOGM is not discovered until after birth when the newborn begin to experience heart failure.

To determine whether a VOGM is the cause of the heart failure or other symptoms your baby may be experiencing, the following tests may be used:

• Computed Tomography (CT) -- A CT scan is a method of body imaging in which a thin X-ray beam rotates around the patient. It can be used to detect the presence of blood in the brain. In addition, three-dimensional models of organs can be created by stacking the individual images.

• Magnetic Resonance Imaging (MRI) -- An MRI scan can detect if there is blood in the brain. It is a non-invasive procedure that uses powerful magnets and radio waves to construct pictures of the body.

• Angiogram -- This is an important test in the diagnosis of VOGM and involves a special X-ray exam that enables a radiologist, a doctor who specializes in understanding and interpreting X-rays, to study a person's blood vessels and organs. Your child's doctor will insert a small tube, called a catheter, into the blood vessel and then inject a special dye that makes the vessels visible on the X-rays. This will allow the doctor to observe how the blood travels through the blood vessels of the brain. The procedure takes about one hour.

Treatment

At UCSF Medical Center, a team of experts specializing in malformations that affect blood vessels in the brain work together with you and your family to develop the best possible treatment plan for your child. This team includes a neurologist, neurosurgeon, and interventional neuroradiologist.

In the past, surgical procedures were used to treat VOGMs, although these techniques were very difficult and often unsuccessful. Today, an alternative treatment called embolization can provide significant improvements.

Embolization

Embolization, in which the blood vessels are intentionally closed, is used as a treatment for many vascular malformations. It may be recommended for certain patients when treatment with surgery is difficult or risky, as is the case with VOGMs, or if the patient cannot have a major surgery because of their medical condition.

Embolization aims to reduce blood flow to the VOGM by obstructing surrounding blood vessels. During this procedure, the VOGM is filled with specially designed coils, glues or spheres, which plug its vessels. Sometimes several procedures are required, which are performed over a period of months, usually while the baby is under two years of age.

Although a VOGM can be a life-threatening disorder, a recent study performed at UCSF showed that the majority of children with this condition will go on to lead normal lives after their VOGM is treated. In addition, children who do not develop heart failure as result of the disease fair particularly well.