Introduction: Giant posterior circulation aneurysms have a very high risk of rupture. Treatment of these lesions, via endovascular or microsurgical approaches, carries a substantial rate of morbidity and mortality. While flow-diverting stents (FDS) represent a potent therapy for endovascular reconstruction of complex aneurysms, they are also associated with novel complications for which effective salvage techniques have not been described.
Methods: We present a unique complication from failed treatment with a FDS.
Results: A 51 year-old male presented with increasing headaches secondary to a giant, fusiform aneurysm of the left posterior cerebral artery (PCA) which was largely thrombosed. Due to progressive enlargement of the aneurysm corresponding to worsening clinical symptoms, the lesion was treated with two Pipeline Embolization Devices (PED). Three months after PED treatment, complete PCA occlusion was observed at the origin of the proximal stent. Despite the lack of arterial inflow, the aneurysm dome continued to grow, resulting in obstructive hydrocephalus. Therefore microsurgical intervention was performed to trap and excise the aneurysm. The sigmoid sinus was injured during the approach which resulted in extensive postoperative venous infarcts and patient mortality.
Conclusions: Successful microsurgical obliteration of aneurysms previously treated with FDSs is extremely difficult. A combination of judicious preoperative planning and meticulous intraoperative surgical technique are requisite for effective management of these complex cases. The optimal microsurgical strategy for aneurysms which have failed endovascular treatment with a FDS is currently unknown.
Patient Care: Flow-diverting stents have become commonly used to treat giant intracranial aneurysms. However, effective microsurgical strategies for aneurysms which have failed endovascular flow diversion have yet to be defined. We describe the potential pitfalls and perils associated with microsurgical treatment of these unique and challenging lesions.
Learning Objectives: By the conclusion of this session, participants should be able to 1) Describe the importance of complete occlusion of giant intracranial aneurysms, 2) Discuss, in small groups the potential complications associated with microsurgical treatment of aneurysms which have undergone prior endovascular flow diversion, and 3) Identify an effective treatment for giant aneurysms which have failed endovascular occlusion with flow-diverting stents.
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