The Virginia Radiosurgery AVM Scale was published as a practical scale to predict favorable outcomes for cerebral AVM patients treated with Gamma Knife radiosurgery (GKRS). The scale assigns 1 point each for AVM volume of 2-4 cm3, eloquent location, or a history of hemorrhage and 2 points for AVM volume greater than 4cm3. In 1012 patients, overall AVM obliteration rate after GKRS was 69%. Morbidities included post-treatment hemorrhage in 88 patients (1.14% yearly incidence), radiation-induced changes in 38.2%, symptoms 9.9%, and permanent deficits in 2.1% of patients. Favorable outcome, defined as AVM obliteration without any post-radiosurgery sequelae, was achieved in 64.1% of patients overall but in 80% of patients with score 0-1 and 70% of patients with a score of 2. Conversely, only 45% of patients with score 3-4 had favorable outcomes. The Virginia Radiosurgery AVM Scale provide a better assessment of long-term outcomes after GKRS compared to the Spetzler-Martin and Radiosurgery-Based Grading Scales.
Journal of Neurosurgery