Surgical exploration after overlapping stents for a ruptured blood blister-like aneurysm: Direct observation of the stent struts through the vessel wall defect and its clinical implications

Background: Blood blister-like aneurysms (BBAs) are a rare but clinically important cause of subarachnoid hemorrhage. Although regrowth or repeat rupture can occur following reconstructive endovascular treatment of BBAs, there is currently a lack of studies reporting the surgical exploration of BBAs after endovascular management. Herein, we present the first case report of a ruptured BBA treated with reconstructive endovascular treatment followed by surgical exploration.Case Presentation: A 42-year-old woman with subarachnoid hemorrhage was found to have the following: a saccular aneurysm of the lateral wall of the right supraclinoid internal carotid artery (ICA); and irregular vessel wall of the anterior wall of the right supraclinoid ICA on angiography. Based on intraoperative findings, the patient was diagnosed with a ruptured BBA of the right ICA. She underwent coating of the dissected ICA followed by overlapping stents; however, angiography showed rapid regrowth of the aneurysm. After high-flow bypass, surgical exploration was performed under proximal control of the cervical ICA. The deployed stent was directly observed through a vessel wall defect of the anterior wall which was consistent with angiographical irregular vessel wall. There was a clear positional discrepancy between angiographical base of the aneurysm and intraoperative laceration site.Conclusions: Surgical exploration indicates there is a potential risk of regrowth and/or repeat rupture of BBAs until the stent is fully endothelialized. Moreover, stent should be deployed to ensure that the irregular vessel wall is included when reconstructive endovascular treatment is employed for ruptured BBAs associated with irregular vessel wall.