A brain arteriovenous malformation (AVM) is an abnormal connection between the arteries and veins in the brain. Although AVMs usually form before birth, symptoms may occur at any age. Brain AVMs have an approximately 4 percent per year risk of bleeding into the brain. AVM bleeding can cause significant neurological deficits; it is even fatal in about 10 percent of cases. AVMs also can irritate the surrounding brain, which can cause seizures and headaches.
Most AVMs can be treated using the following techniques:
- Two-step treatment
- Endovascular embolization: A catheter is inserted through a leg artery into the AVM vessels in the brain. The AVM is then completely filled with surgical glue (Onyx), shutting it down from the inside.
- Surgical resection: Brain surgery is performed through an opening in the skull to remove the AVM. This is much easier and safer if the AVM has already been embolized with Onyx glue.
- Stereotactic radiosurgery – A focused beam of radiation is directed at the AVM, which causes shrinkage and closure over a two- to three-year time period.
- Conservative therapy – Closely monitoring the AVM is chosen in rare cases where the risk of treatment exceeds the risks associated with living with the AVM.
- Treatment options are tailored to individual patients. Patient preference, age, as well as AVM size and location, are important considerations.
- A bleeding AVM is a medical emergency. The goal of treatment is to prevent further complications by controlling bleeding and seizures and, if possible, removing the AVM.
Shervin R. Dashti, M.D., Ph.D., and Tom L. Yao, M.D., are two of a very small number of endovascular neurosurgeons in the country who can provide comprehensive AVM treatment. Because they are fellowship trained in state-of-the-art endovascular techniques, they can embolize AVMs to make surgery significantly safer.