THE ROLE OF RADIOSURGERY AND PARTICULATE EMBOLIZATION IN THE TREATMENT OF DURAL ARTERIOVENOUS-FISTULAS

Over the past 5 years 29 patients with dural arteriovenous fistulas (A VFs) were treated by the authors using the Leksell radiosurgical gamma knife unit. Within 2 days after radiosurgery, 17 patients with AVFs t hat exhibited retrograde pial or cortical venous drainage (12 patients ) and/or produced intractable bruit (eight patients) underwent particu late embolization of external carotid feeding vessels. The rationale f or this treatment strategy was that radiosurgery was expected to cause obliteration of most fistulas after 12 to 36 months. In patients with bruit, ocular symptoms, or in those at risk for hemorrhage, treatment with embolization after radiosurgery kept the fistulas angiographical ly visible for radiosurgical targeting yet offered palliation of sympt oms and temporary, partial protection from hemorrhage during the laten cy period. In 12 patients, preobliteration embolization immediately re duced (10 patients) or eliminated (two patients) retrograde pial venou s drainage. To date, no lesion has hemorrhaged after treatment. Angiog raphy I to 3 years posttreatment in 18 patients showed total obliterat ion of 13 fistulas (72%) and partial obliteration of five (28%). Radio surgery, followed by embolization when retrograde pial venous drainage , intractable bruit, and/or major external carotid artery supply is pr esent, appears to be a promising treatment for selected patients with symptomatic dural AVFs.