Treatment of a Ruptured Basilar Artery Perforator Aneurysm in the Subacute Phase Using Overlapping LVIS Blue Stents: A Case Report and Review of the Literature.

Objective: Basilar artery perforator aneurysms (BAPAs) are rare causes of subarachnoid hemorrhage (SAH), and their optimal treatment strategy remains controversial. We report a case of ruptured BAPA successfully treated in the subacute phase with an overlapping stent technique using LVIS Blue stents (Terumo Neuro, Tustin, CA, USA). Case Presentation: A 75-year-old woman presented with SAH (Hunt and Hess grade II). Non-contrast head CT demonstrated SAH predominantly in the posterior cranial fossa. Initial DSA performed on the day of onset did not demonstrate a definite aneurysmal lesion; however, subtle focal contrast pooling was observed along the basilar artery (BA) trunk. Repeat DSA performed 4 days later revealed a small saccular dilatation arising from the BA trunk adjacent to a perforating artery. Although initial conservative management was selected, subsequent follow-up angiography demonstrated enlargement of the aneurysmal dilatation. Endovascular treatment with deployment of 2 overlapping LVIS Blue stents was performed on day 16 after onset. The postoperative course was clinically uneventful, with no rebleeding or symptomatic complications; a small asymptomatic diffusion-weighted imaging lesion was noted postoperatively. Follow-up DSA at 1 month demonstrated complete obliteration of the aneurysm. Conclusion: The stent-overlap technique represents a feasible and effective treatment option for ruptured BAPAs. In particular, overlapping stent placement appears to be effective for basilar trunk-related subtypes, in which adequate flow diversion can be achieved while preserving perforator patency.