A cavernous hemangiomas is an abnormal tangle of tightly packed, thin-walled capillaries that are prone to bleeding. In the brain, cavernous hemangiomas may remain stable for years and never cause symptoms or may bleed one or more times and cause seizures or stroke. Treatments include observation, medications and surgery.
A cavernous hemangioma is an abnormal cluster of tightly packed, thin-walled capillaries (smallest blood vessels). The thin walls of these capillaries make hemangiomas prone to bleeding. The blood within the capillaries is usually slow-moving or not moving at all.
Cavernous hemangiomas are also called cerebral cavernous malformation, cavernoma, occult vascular malformations or cavernous malformations.
A cavernous hemangioma looks like a raspberry. It has blood-filled spaces, separated by connective tissue. Hemangiomas can range in size from a fraction of an inch to dime-sized or larger.
Cavernous hemangiomas can affect about 1 in 200 people. They’re usually discovered between the ages 20 and 30 years old. Although they are quite common, only 1 in 10 people will ever develop symptoms.
Cerebral cavernous hemangiomas usually aren’t discovered until they rupture and bleed, which can cause symptoms including stroke or seizure. You could, however, have a rupture of a cavernous hemangioma and still never have any symptoms. In this case, a cavernous hemangioma would only be discovered if you had a brain scan for another reason.
Yes, it’s possible to have more than one cavernous hemangioma. Having more than one lesion doesn’t necessarily mean you’ll develop symptoms. It’s possible to have several malformations that remain stable for years and never cause any symptoms. On the other hand, a single cavernous hemangioma may bleed and cause a lot of damage and symptoms.
About 20% of cavernous malformations are genetic (run in families). These are caused by a mutation in any one of three genes. If you have a cavernous malformation, your children have about a 50% chance of having one too. Having more than one cerebral cavernous hemangioma is more common in people with a family history. People with a genetic link are also more likely to develop new cavernous hemangiomas over time.
People at higher risk for the hereditary form are:
Another common type of blood vessel malformation is an arteriovenous malformation (AVM). Unlike cavernous malformations, which are filled with slow-moving or stagnant (not moving) blood, AVMs involve high-pressure blood flow.
Cavernous malformations and AVMs can be similar in size, depending on the number of blood vessels involved. They can both rupture and bleed. If they do bleed, however, the high-pressure blood flow of an AVM can be more severe and cause more damage.
After AVMs, cavernous malformations are the most likely type of blood vessel lesion to need treatment. Surgery, as well as other options, is available for treating AVMs. Cavernous malformations, however, are best treated with surgery to remove the lesion.
Two other types of blood vessel malformations are capillary telangiectases and venous malformations. These lesions rarely rupture or cause damage.
The number and severity of symptoms depends on the size, location and number of hemangiomas. Some individuals don’t have any symptoms. Symptoms vary from person to person.
About 80% of cerebral cavernous hemangioma don’t have an identifiable cause. These are known as sporadic cavernous hemangiomas. Usually only one hemangioma forms.
Researchers have found that another type of abnormal blood vessel, known as a developmental venous anomaly (DVA), increases the chance of developing a cavernous hemangioma. Radiation treatment to the brain or spine is another known cause of cavernous hemangiomas.
About 20% of cavernous hemangiomas have a hereditary link.
Cerebral cavernous hemangiomas can rupture and bleed and cause seizures or stroke. Risks from surgery to remove a cavernous hemangioma include stroke, paralysis, coma or death. Many factors determine risk including your general health, the size and location of the lesion, number of lesions and the skill and experience of your neurosurgeon.
Cavernous malformations are diagnosed by magnetic resonance imaging (MRI). A special type of scan, called susceptibility weighted imaging, is a more sensitive type of MRI. It detects the tiniest cavernous hemangiomas as well as remnants of prior bleeds or swelling around the lesion. This information helps give your healthcare team some idea about the risk for future complications.
Most lesions never bleed. However, if the cavernous hemangioma in your brain has bled once, you have about a 1 in 5 chance (20%) that it will bleed again within five years. If the hemangioma is in your brainstem, the chance of a second bleed is 1 in 3 (30%) over the next five years. After five years, the risk of another bleed slowly returns to the risk of having a lesion that never bleeds.
Treatment options depend on the location of your cavernous hemangioma(s) in your brain and if they have bled and are causing uncontrollable symptoms.
If your cavernous hemangioma is not causing symptoms, your neurosurgeon may simply want to watch it with regularly scheduled brain scans. Your healthcare provider will prescribe medication to manage your symptoms such as headache and seizures.
Surgery to remove your cavernous hemangioma is the main treatment approach if you’re having symptoms. Surgery is more likely if:
Your hemangioma’s location is also considered. Your neurosurgeon will decide if removing your hemangioma is less disruptive to your brain tissue than the risk of damage from additional bleeds.
No, generally these malformations can’t be prevented. If there’s a family history of these lesions, a geneticist will discuss testing and provide counseling.
You can, however, control some general health risk factors to decrease your chance of hemorrhage. These include:
Make an annual appointment for a general health checkup. Take all medications as directed by your provider or the package labeling. Never stop taking your medication or change the dose without talking to your provider first.
If you have a cavernous hemangioma that has bled and causes symptoms, such as seizures, surgery to remove the lesion may be recommended. Surgery is most successful if it’s performed within two years of the first seizure.
If you have more than one cavernous hemangiomas or hemangiomas that have not bled or are not causing symptoms, your neurologist will discuss how often to have MRI scans to watch these lesions.
Many factors determine if cavernous hemangiomas are life-threatening:
Because each person’s situation is unique, it’s best to ask your neurosurgeon about your risk for life-threatening events.
Cavernous hemangiomas can occur anywhere in your body. They usually only cause serious problems in the brain or spinal cord. Other common organs include the skin, liver and eye.
It’s unclear if hormone therapy for birth control or estrogen supplements play a role in causing a cavernous hemangioma to bleed. If you’ve experienced a previous bleed while on these medications, your healthcare provider may want you to stop using these products. But there is no firm evidence, and the decision to continue or stop these medications is between you and your healthcare team.
Yes, there’s no reason to avoid flying.
If you want to become pregnant and currently take anti-seizure medication, talk with your healthcare provider right away. Some anti-seizure drugs can increase the risk of birth defects if taken during the early weeks of pregnancy. Experts believe there’s no increased risk of a brain bleed during pregnancy. Vaginal delivery is also OK as long as you have not had a recent brain bleed. Surgery to remove a cavernous malformation during a pregnancy is rarely considered unless there’s suspicion that an additional bleed would be life-threatening.
A note from Cleveland Clinic
Hearing that you have a diagnosis of cerebral cavernous hemangiomas can be difficult and scary. Each individual’s experience with hemangiomas is unique. You may have one or more cavernous hemangiomas and not have any symptoms at all. In this case, you may simply need follow-up scans from time to time.
If your cavernous hemangioma causes symptoms, medications to manage the symptoms may be tried first. If your hemangioma has repeatedly bled and causes symptoms that can’t be managed with medications, surgery to remove the lesion may be the best option. The key to successfully manage this condition is having an experienced and skilled neurology and neurosurgery team along with counselors to help you cope with stress and anxiety. Ask your healthcare team about support groups, genetic testing and any other questions and concerns you may have.
Last reviewed by a Cleveland Clinic medical professional on 08/26/2021.
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