Progressive deconstruction: a novel aneurysm treatment using the pipeline embolization device for competitive flow diversion: case report.

BACKGROUND AND IMPORTANCE:A variety of deconstructive and reconstructive therapies have been used to treat intracranial aneurysms. The Pipeline embolization device (PED) has become a quite successful option to treat aneurysms, while reconstructing and remodeling the parent vessel. We report a case of off-label PED use, where a flow diverter was placed across the parent vessel of a giant intracranial aneurysm in a novel deconstructive strategy. CLINICAL PRESENTATION:A 40-year-old man with a giant, slow-flow aneurysm of the distal middle cerebral artery (MCA) was treated with the placement of a PED across the vessel containing the aneurysm after superselective test balloon occlusion of that vessel failed. PED was successfully deployed in a competing MCA branch across the origin of the MCA branch supplying the giant aneurysm. The patient continued dual-antiplatelet therapy for 5 months and aspirin monotherapy thereafter. Follow-up angiography, performed 6 months after treatment, demonstrated complete and asymptomatic thrombosis of the aneurysm and its parent MCA branch. A collateral pial and leptomeningeal network developed, reconstructing the distal branches of the occluded MCA branch. After 18 months, the patient remains neurologically intact. CONCLUSION:This appears to be the first description of progressive deconstruction for aneurysm treatment by using PED. Despite not tolerating acute vessel occlusion with superselective test balloon occlusion, the patient was asymptomatic following long-term occlusion with PED secondary to the growth of pial and leptomeningeal collateral networks.