Gamma Knife Radiosurgery for Dural Arteriovenous Fistulas

Abstract

BACKGROUND: The current management of intracranial dural arteriovenous fistulas (dAVFs) incorporates a multimodal approach involving microneurosurgery, endovascular embolization, and radiosurgery. OBJECTIVE: To explore the role of Gamma Knife radiosurgery for dAVFs. METHODS: The series includes patients with dAVFs who had Gamma Knife radiosurgery at the University of Virginia Medical Center between 1989 and 2005 with clinical follow-up through 2008. Medical records were reviewed to obtain clinical history, demographic data, and dosimetry. Radiographic records provided the location and anatomy of the dAVFs. Follow-up angiography was performed 2 to 3 years after treatment, with cure defined as complete obliteration of fistulous flow. Follow-up for clinical symptomology and quality of life was obtained from direct patient and primary physician questionnaires. RESULTS: Fifty-five patients underwent Gamma Knife radiosurgery for dAVFs during the study period. Twenty patients (36%) presented with intracranial hemorrhage before radiosurgery. Gamma Knife radiosurgery was preceded by craniotomy for microneurosurgical ablation in 11 patients (20%) or endovascular embolization in 36 patients (65%). Follow-up angiography was performed on 46 patients (83%) with documented obliteration in 30 patients (65%). Patients lost to follow-up were classified as treatment failures, adjusting the range of efficacy from 65% to 54%. Three patients (5%) suffered a posttreatment hemorrhage during the follow-up period, but no new permanent neurological deficits resulted from these events. CONCLUSION: Gamma Knife radiosurgery is an effective adjunct therapy for dAVFs with persistence of flow after open neurosurgical resection or endovascular treatment while still maintaining a role in nonaggressive dAVFs not amenable to either surgery or embolization.