Surgical treatment of blood blister–like aneurysms of the supraclinoid internal carotid artery with extracranial–intracranial bypass and trapping

Abstract

Object Blood blister–like aneurysms (BBAs) arise from the supraclinoid internal carotid artery (ICA) at non-branching sites. These aneurysms are challenging to treat primarily with either surgical clip placement or endovascular therapy. The authors describe a series of 4 patients who presented with high-grade subarachnoid hemorrhage (SAH) due to a BBA, which was treated with an extracranial–intracranial (EC–IC) bypass followed by trapping of the aneurysm. Methods Four patients presented with SAH due to a BBA of the ICA. Three of these patients were treated with an endovascular procedure; following the vasospasm period, definitive treatment with EC–IC bypass followed by trapping of the aneurysmal parent vessel was performed. Results Two of the patients who were treated endovascularly suffered rebleeding prior to bypass and trapping. Three of the 4 patients had a good outcome (modified Rankin Scale Score 1 or 2), and 1 patient who suffered 2 episodes of rebleeding died. Conclusions Treatment of BBAs of the ICA remains difficult, particularly in the setting of high-grade SAH. Patients with this challenging condition often require multiple procedures and have a high incidence of rebleeding. Definitive treatment of these aneurysms consists of EC–IC bypass and surgical or endovascular trapping.