Pre-LINAC Evaluation for AVM

AVMs are the lesions most commonly treated with the LINAC Scalpel at the University of Florida Shands Neurological Center.

The major criterion for selection of treatable AVMs is size. Patients presenting AVMs that are less than 4 cm in diameter are candidates for LINAC treatment. The University of Florida College of Medicine neurosurgeons prefer to treat AVMs that have not ruptured and that are in deep locations in the brain with radiosurgery. AVMs that have ruptured or that are in relatively silent brain areas are typically treated with open surgery. A multi-evaluative approach is used in determining these parameters and in deciding the mode of therapy.

Referring physicians should send actual CT, MRI and angiography films, as well as any hospital and office records, to the University of Florida, College of Medicine, Department of Neurosurgery.

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Risks of LINAC Treatment

There is no known acute risk of radiosurgical therapy, which allows patients to be treated on an outpatient basis. Thrombosis of AVMs usually takes up to three years, with about 40 percent of AVM patients thrombosing one year after treatment and about 80 percent thrombosing three years after treatment. The frequency of rehemorrhage is about 3 percent of AVM patients per year and remains so until the AVM is completely thrombosed.

There is a small incidence of delayed side effects from treatment related to the radiation. Radiation necrosis of the brain tissue around the AVM can cause a variety of neurological complications, depending on the location of the lesion. This occurs in less than 2 percent of AVM patients

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Post-LINAC Treatment

Follow-up assessment of AVM patients involves an MRI scan every 12 months after treatment and an angiogram two to three years after treatment.

Patients may choose to have follow-up X-rays taken at medical facilities other than Shands Hospital at the University of Florida.

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Indications for Radiosurgical Treatment

General indications for radiosurgical treatment, as opposed to open surgical treatment, are as follows:

1. Surgically inoperable lesions.

2. Lesions that have recurred or persisted after surgery.

3. Medically infirm patients.

4. Patients who refuse open surgical treatment.