Introduction: The Pipeline Embolization Device (PED) has been demonstrated to be an effective treatment approach for complex intracranial aneurysms. Intraprocedural complications during PED deployment are seldom reported.

Methods: We report a rare complication of a PED malfunction identified immediately following complete deployment during endovascular treatment of a giant middle cerebral artery (MCA) bifurcation aneurysm.

Results: After multiple failed attempts at endovascular retrieval of the malfunctioned PED, the patient was taken for microsurgical extraction due to accumulation of thrombus on the proximal unopened portion of the stent and widespread distal dissemination of emboli. After removing the PED from the vessel lumen and resecting the giant aneurysm, the proximal MCA was unable to be reanastamosed to the distal segment.

Conclusions: The management of PED malfunction is poorly understood. While removal of an incompletely deployed PED may be undertaken with limited adverse effects, retrieval of a fully deployed PED is associated with a much higher risk of morbidity. Until larger case series of such complications are able to better define the risks and benefits of endovascular or microsurgical retrieval of malfunctioned PEDs, the management of these rare intraprocedural complications will remain based on the unique aspects of each individual case and the expertise of the treating neurointerventionalist.

Patient Care: As the utilization of the Pipeline Embolization Device for intracranial aneurysm treatment becomes increasingly popular, rare but devastating complications, such as malfunction following complete deployment, should be recognized as potential sentinel events. The best management strategy for this event is currently unknown, but we propose microsurgical extraction as a potential, although imperfect, solution.

Learning Objectives: By the conclusion of this session, participants should be able to 1) Describe the importance of properly managing pipeline stent malfunction, 2) Discuss, in small groups the efficacy of microsurgical pipeline stent extraction, and 3) Identify an effective treatment for malfunctioned pipeline stents unable to be salvaged with endovascular techniques.

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