Health Library

Cavernous Malformations

A cavernous malformation is a group of small blood vessels (capillaries) in the brain that bind together to form a small tunnel of blood in the brain. The malformations can vary in size. They may be as small as a pea or up to five inches long.

Blood inside a cavernoma does not circulate normally. It often moves very slowly. As the volume of blood inside the cavernoma increases, it may grow in size and push on other areas of the brain, causing a variety of symptoms.

Because small blood vessels have thinner walls than other larger vessels, their expansion to hold too much blood may even cause them to burst and bleed inside the brain. Your child's neurosurgeon may suggest surgery if the cavernous malformation is bleeding into the brain or pushing on certain parts of the brain.

What are the Symptoms of Cavernous Malformation?

Symptoms happen when the cavernoma either presses on another area of the brain or begins to bleed. Symptoms may include:

• Headaches
• Seizures
• Trouble speaking
• Vision changes
• Balance problems
• Weakness or numbness in arms or legs
• Gradual or sudden changes in personality

Most cases of cavernoma bleeding involve very small amounts of blood that may not cause any symptoms. If there is a larger amount of bleeding, symptoms will develop more quickly. This potentially life-threatening situation requires immediate treatment.

What Causes a Cavernous Malformation?

Approximately one in four cases of cavernous malformation are inherited. The remaining cases have no clear cause.

People with inherited cavernous malformations are more likely to have multiple cavernomas in the brain, increasing their risk of developing symptoms. Half of the people who inherit cavernous malformations will pass the condition on to their children.

Non-inherited cases often result in just one cavernoma with few or no symptoms.

How Common are Cavernous Malformations?

Cavernous malformations occur in less than one in 1,000 births. Most children and adults with non-inherited cavernomas never have symptoms and often go undiagnosed. If a person does have symptoms, they typically develop before the age of 30.

Cavernous malformations affect all ethnic groups. Females and males have an equal chance of having the disease.

How is a Cavernous Malformation Diagnosed?

In order to properly diagnose and locate cavernous malformations, magnetic resonance imaging (MRI) or computed tomography (CT) may be used to see two- or three-dimensional images of the brain. These tests will identify cavernomas and often show any bleeding that may have occurred.

How is a Cavernous Malformation Treated?

The goal of treatment is to:

• identify and surgically handle life-threatening cases of cavernous malformation
• relieve symptoms in patients with non-life-threatening cavernous malformations

In non-life-threatening cases, the care team will first verify that your child’s symptoms are truly caused by the cavernous malformation(s) before suggesting specific treatment. If your child has multiple cavernomas, the care team will observe your child to try to identify whether one or more cavernomas are causing the symptoms.

If surgery is recommended, the surgeon will explain the location of the cavernoma(s) and identify potential risks of surgical removal.

There are currently no drug treatments for cavernous malformations; however, there are drug treatments that can help treat symptoms such as seizures or headache. 

What Are the Risks and Complications of Surgery?

As with any surgical procedure, there are possible complications. Risk levels vary depending on the location of the cavernoma(s) in the brain.

Most complications with cavernous malformations are neurological in nature. Complications may include:

• Stroke
• Paralysis
• Coma

Such complications may require additional treatment and/or surgery. Talk with your child's care team if you have concerns about surgery.

Recovery

Your surgeon will provide specific instructions during your child’s recovery period. Most children are able to leave the hospital within one week of surgery. Your child may return to normal life within a month following surgery. Doctors will continue to monitor your child’s condition in the following weeks and months.

If other neurological problems arise, your child may receive additional treatment from a variety of specialists (neurologists, physical therapists, speech therapists, etc.).

What is the Prognosis for Children with Cavernous Malformation?

Long-term outlook is good for most children with one or more cavernous malformations. They typically go on to live normal lives.

It is difficult to identify specific causes of bleeding in the brain. Your child's doctor may recommend avoiding of high-impact sports and activities that may result in significant head trauma.