Cavernous Malformations

What is a cavernous malformation?

A cavernous malformation is a small mass that is made up of abnormal, thin-walled blood vessels. These malformations are sometimes called cavernomas, cavernous hemangiomas, or occult vascular malformations. Most cavernous malformations are congenital (present at birth).

Cavernous malformations can occur anywhere in the body, but usually only cause serious problems in the brain and spinal cord. They are one of the more common cerebrovascular problems in children. While many people with cavernous malformations never have any problems, they can cause neurologic symptoms and can sometimes be life threatening.

In most cases, cavernous malformations are not diagnosed unless there are symptoms.

What are the symptoms of cavernous malformations?

Symptoms occur when the cavernous malformation bleeds.

Symptoms can vary depending on where the cavernous malformation is located, but may include:

  • weakness in the arms or legs
  • seizures
  • headaches
  • dizziness
  • irritability
  • changes in personality

These symptoms may appear and then go away as the malformation bleeds and then reabsorbs blood.

What causes cavernous malformations?

The exact cause of cavernous malformations is not well understood, though some types may be inherited. If many family members have seizure disorders or blood vessel abnormalities on the skin, other family members may be at higher risk for a cavernous malformation.

The malformation results when small blood vessels (capillaries) within the brain group into enlarged or irregular masses. Compared to other blood vessels, capillaries have thin walls. So when they stretch out from excessive blood flow, they often cannot return to their normal size.

Head trauma may increase the risk for cavernous malformations to bleed, so doctors recommend that children with cavernous malformations avoid activities and sports with a high likelihood of head trauma, such as football.

Care for cavernous malformations

At Boston Children’s Hospital, our expert clinicians in the Cerebrovascular Surgery and Interventions Center treat cavernous malformations and other cerebrovascular conditions.