Pipeline Flex Embolization of Flow-Related Aneurysms Associated with Arteriovenous Malformations: A Case Report.

Background: An estimated 0.1% of the population harbors brain arteriovenous malformations (AVMs). Diagnosis and workup of AVMs include thorough evaluation for characterization of AVM angioarchitecture and careful assessment for concomitant aneurysms. The presence of coexisting aneurysms is associated with an increased risk of intracranial hemorrhage, with a published risk of 7% per year compared to patients with AVMs alone with a risk of 3%. Comprehensive AVM management requires recognition of concomitant aneurysms and prioritizes treatment strategies to mitigate the aggregate risk of intracranial hemorrhage associated with AVM rupture in patients with coexisting aneurysms. Endovascular treatment of these flow-related aneurysms can offer a cure, while avoiding open surgery. Successful flow-diverting embolization techniques, efficacy, and outcomes have been previously described for a variety of aneurysm types and locations. However, use of a flow diverter has not been previously described for the treatment of high-flow aneurysms on AVM-feeding vessels.

Case presentation: We report 2 cases of large AVMs within eloquent cortex associated with flow-related aneurysms in patients presenting initially with suspected intracerebral hemorrhage secondary to AVM rupture.

Discussion: No consensus currently exists to guide treatment of intracranial aneurysms associated with AVMs. Surgical management addressed AVM embolization initially, as the vasculopathology with the highest rupture risk. Subsequently, Pipeline embolization of the associated aneurysms with adequate antiplatelet treatment was performed before scheduled radiosurgery to decrease the risk of AVM rupture or rebleed. This represents a novel and promising use of the Pipeline Embolization Device. Additional cases and longer follow-up will be needed to further assess the efficacy of this technique.