Brain and spinal cord cavernous malformations are an abnormal tangle of vein-like structures. Unlike arteriovenous malformations, these do not have a high blood flow traveling through them. (They are also known as cavernous angiomas, cavernomas, or cavernous hemangiomas.)
If the malformation isn't causing symptoms and doesn't appear to be growing rapidly, all that may be needed to regular monitoring. This is done by having MRI scans or CT scans every couple of years. Doing scans more often may be recommended if the cavernous malformation appears to be bleeding or growing. Anti-seizure medications may be necessary in patients who present with seizures.
A cavernous malformation is usually found because:
- It has started to bleed. The bleeding can cause symptoms similar to a stroke. The bleeding also tends to build a shell of blood products around the cavernous malformation. This irritates the tissues of the brain and may cause seizures.
- The shell of blood products that has built up around the malformation has created a tumor-like mass. The mass presses on parts of the brain responsible for movement, vision, speech or sensation. As a result a person may have weakness, numbness, vision problems, speech problems, difficulty moving the eyes, difficulty swallowing and coordination and balance problems.
- A computed tomography (CT) scan or magnetic resonance imaging scan was done to investigate neurological symptoms or another condition and the malformation was visible.
The impact that a cavernous malformation makes on a person varies greatly.
A neurosurgeon will take many factors into consideration before deciding on an approach to treatment, including:
- The patient's age
- The location of the malformation. Some malformations are easier to reach surgically. Removing them carries less risk and fewer complications than a malformation that is deep within the brain.
- The size of the malformation. Cavernous malformations can range in size from less than a quarter of an inch to the size of a tangerine. The larger the malformation is the more likely it is to cause problems for the patient.
- Whether the malformation shows signs of bleeding. Bleeding may cause symptoms similar to those of a stroke. It also causes a cavernous malformation to get larger. The blood itself can irritate the tissues of the brain and cause seizures.
- The symptoms that it is causing. A cavernous malformation that is stable and not bleeding may cause no symptoms. All that may be needed is regular observation.
- How fast the cavernous malformation is growing. A malformation that has had bleeding is more likely to bleed again. If the malformation is growing at a fairly rapid rate, it may be necessary to remove it.
Surgical Removal of Cavernous Malformations
If the cavernous malformation is causing symptoms or is growing, doing surgery to remove the malformation may be recommended.
Surgery can be very effective if the malformation is located in an accessible part of the brain. The entire cavernous malformation must be removed. If any part is left behind, it may start growing again.
A newer approach to treating cavernous malformations is stereotactic radiosurgery. This approach is useful when cavernous malformations are repeatedly bleeding and are located in parts of the brain that aren't otherwise accessible by surgery because they are deep within the brain.
Stereotactic radiosurgery uses precisely focused radiation to treat cavernous malformations. Three-dimensional, computer-generated images guide the oncologists and surgeons in aiming radiation from several sources at the malformation.
The may be used for treatments in the brain. The doses of radiation given are very high. But because they are precisely aimed, there is little risk to the surrounding tissue.
Stereotactic radiosurgery doesn't require the patient to have general anesthesia. No incision is made in the body. As a result, there is no need to shave the patient's head or body. Radiosurgery takes about one to four hours. A patient is able to go home the same day and return to normal activities the following day. Sometimes more than one treatment is needed.
(Radiosurgery is different than radiation therapy that is sometimes given to cancer patients. Radiation therapy gives the patient radiation in low doses over a series of sessions. It is less precisely targeted.)