Cavernous malformations, also called cavernous venous malformations or, when they are in the brain, cerebral cavernous malformations, occur when the blood vessels don’t form correctly.
In this condition, tiny blood vessels called capillaries group together. They grow with extremely thin walls that can leak easily. These are called “lesions.” These clusters of blood vessels can be from 2 to 55 mm wide, or from about the width of a paperclip to more than 2 inches wide.
They can form anywhere in the body. When they grow in the brain or spinal cord, they are most likely to cause symptoms such as headaches or seizures. Experiencing symptoms depends on where the lesions grow and how many of the lesions are present.
Most of the time, these formations cause no problems. Many people never know that they have one. For some people, the lesions can burst and bleed into the brain, causing stroke and death.
About one in 200 people have cavernous malformations. Between one in 2,000 and one in 10,000 occur in the brain. The malformations probably form before or shortly after birth. Some may come and go.
Some experts believe that cavernous malformations run in families. Researchers have found genes that seem to be linked to a risk of these unusual formations. Some cases of cavernous malformations may be genetic, but others appear without a family history.
Symptoms of cavernous malformations depend on the location and size of the malformation. Although children sometimes have symptoms, most people who have symptoms are between 20 and 50 years old.
These are physical symptoms:
Changes in hearing or vision
Difficulty thinking clearly or with remembering things
Complications of cavernous malformations include:
Most people only find out about a cavernous malformation when it bleeds. This causes stroke in some people. If you notice symptoms such as seizure, numbness, vomiting, or physical weakness, go immediately to the emergency room or call 911 to get help.
Doctors typically take a medical history and do a physical exam. The final diagnosis is usually made based on imaging tests that show areas of blood flow. These tests could include:
Gene testing is available in some clinics
A treatment plan could include:
Medication for symptoms, such as antiepileptic drugs for seizures
Surgery to remove the blood vessels
Currently, cavernous malformations can’t be prevented. Researchers hope that by learning more about the genes linked to these growths, prevention could become possible. Prenatal genetic testing and counseling are options in some clinics.