Aggressive cavernous sinus dural arteriovenous fistula: Angioarchitecture analysis and embolization by various approaches

Background: Most cavernous sinus dural arteriovenous fistulas (CSDAVFs) present with benign neuro-ophthalmic symptoms. CSDAVFs manifesting with aggressive neurologic symptoms are rare. The purpose of this study was to analyze the different angioarchitectures of aggressive CSDAVFs and to report our experiences of embolization.

Methods: Over the past 10 years, a total of 118 CSDAVFs were managed by embolization. From the databases containing such patient information, nine patients (7.6%) were found to have aggressive CSDAVFs presenting with neurologic deficits. There were seven women and two men, ranging in age from 51 years to 78 years (mean, 66 years). We retrospectively analyzed the angioarchitectures of aggressive CSDAVFs, further reviewing patient and angiographic as well clinical outcomes after embolization.

Results: The cause of clinically aggressive CSDAVFs was insufficient fistula drainage because of occlusion (n = 6) or stenosis (n = 1) of the inferior petrous sinus (IPS) or compartment of IPS-cavernous sinus (n = 2) with fistula flow reflux to the veins of brainstem (n = 7) leading to brainstem ischemia, while two fistula flow reflux to the cortical vein leading to cerebral infarction. Transvenous embolization via IPS to fistula was achieved in one case; six patients underwent transorbital access, while transarterial embolization was performed in two cases. Total fistula occlusion was achieved in eight CSDAVFs. All patients had total (n = 7) or partial (n = 2) resolution of their symptoms gradually within 6 months. One patient undergoing transarterial embolization had limb weakness because of inadvertent pial artery occlusion. Their overall mean clinical follow-up period was 17 months.

Conclusion: Aggressive CSDAVFs are associated with occlusion/stenosis of the IPS or compartment of IPS-cavernous sinus with leptomeningeal reflux. In this limited case series, aggressive CSDAVFs most presented with brainstem ischemia, followed by nonhemorrhagic/hemorrhagic stroke in the cerebrum. Embolization through various access routes is a feasible method to manage these aggressive CSDAVFs, with an acceptable level of periprocedural risks.